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Herd health and welfare - More Beef Module 7

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					         Herd health and welfare

                       Key actions
                       3 Know the common cattle diseases in your locality and whether
                           they are likely to affect production.
                       3 Map any historic areas or sites of old yards and stock routes for
                           potential disease.
                       3 Implement a disease management plan using veterinary advice.
                       3 Vaccinate against specific diseases that can infect cattle and
                           people.
                       3 Seek veterinary advice for any unexplained health problem.
                       3 Quarantine all introduced stock to prevent the transfer of
                           infectious diseases.




                    Introduction
                    Why is the health and welfare of your herd important?

Manage cattle       A well-planned approach to managing cattle health and welfare controls the risk
health and          of disease in a cost-effective way and maximises the production potential of your
welfare to          herd. This module outlines the four key procedures required to manage a healthy
maximise herd
                    beef cattle herd.
productivity
                    A sound animal health management plan uses preventative approaches to avoid
Use a
combination
                    disease from striking, and early treatment in the event that it does. If treatment is
of disease          necessary, it should involve the use of as few chemicals as possible. Access to
prevention          both domestic and export markets is dependent on product being free from
and treatment       chemical and pesticide residues. Consumers of beef want safe, wholesome meat
                    produced with a minimum use of chemicals. Also, the overuse of some chemicals
Use chemicals at    to treat disease has led to them becoming ineffective and there are few new
their correct
                    options available to producers.
application rates
as per
recommendations




                      MLA More Beef from Pastures – Module 7: Herd health and welfare                 1
Introduction
                       How does this module assist you?
                       This module describes how to prevent health problems in preference to reacting
                       after disease has already affected the herd. It is based on:
                       • Knowing the conditions that can influence cattle health;
                       • Applying the right management strategy or treatment when your cattle are at
                         risk; and
                       • Preventing the introduction of infectious diseases onto the property.



                       Linkages to other modules
                       This module outlines the procedures required to manage a healthy cattle herd.
                       Without implementing these procedures, producers cannot achieve the
                       productivity gains possible from purchasing additional stock when a period of
                       excess pasture is predicted (see Module 2: Tactical stock control), procedures to
                       better utilise pasture (see Module 4: Pasture utilisation) and boosting weaner
                       throughput (see Module 6: Weaner throughput). Following the four procedures
                       will also help producers to meet market specifications (see Module 8: Meeting
                       market specifications).
        Introduction




                        2            MLA More Beef from Pastures – Module 7: Herd health and welfare
Principles of herd health and welfare




                                                                       Principles
 Know the most important cattle diseases and disorders
              in your locality or region.




           Disease prevention is more effective and
                  less costly than treatment.




 MLA More Beef from Pastures – Module 7: Herd health and welfare   3
             Procedures for managing the health
             and welfare of your herd


                    Procedure 2                             Procedure 3
                 Determine the risk and                   Watch for sporadic
                  vaccinate for specific                diseases and disorders.
                        diseases.
Procedures




                 Procedure 1                                  Procedure 4
                     Choose the
                                                            Prevent introduction
                     appropriate
                                                                of infectious
                    management
                                                                  diseases.
                 practice, corrective
                  treatment, or a
                   combination to
                  prevent common
                     diseases or
                      disorders.




                   Managing herd health and welfare




             4           MLA More Beef from Pastures – Module 7: Herd health and welfare
                Procedure 1
                Choose the appropriate management practice, corrective
                treatment or a combination to prevent common diseases
                or disorders


                Guidelines for choosing the appropriate disease management practice
                All the procedures in this module rely on knowing the health problems that are
                potential risks to your beef enterprise.
                Consider whether any of the more common diseases or trace element deficiencies
Know the
                are likely to occur in your beef enterprise by assessing:
common cattle
diseases in
                •   Grazing and husbandry practices;
your locality
                •   Age groups and classes of cattle;
                •   Disease status of introduced cattle;




                                                                                                           Procedure 1
                •   The locality of your enterprise.
                Tool 7.1 provides a list of common production and reproduction diseases and
                conditions for their likely occurrence. These diseases of cattle can lead to significant
                economic loss when left untreated or treatment is delayed.
                The diseases discussed in this procedure include:
                •   Gastrointestinal parasites
                •   Liver fluke
                •   Grass tetany (hypomagnesemia)
                •   Milk fever (hypocalcaemia)
                •   Bloat
                •   Mineral deficiencies (copper, cobalt, selenium, phosphorus)
                •   Ketosis/pregnancy toxaemia
                Important reproductive diseases include:
                •   Vibriosis
                •   Trichomoniasis
                •   Leptospirosis
                •   Bovine pestivirus or mucosal disease
                Consult with neighbours, producers with similar production systems, local veterinary
Use local and   practitioners, state departments of agriculture and their animal health websites to
veterinary      assist with a thorough assessment of the disease status of your herd.
advice to
develop a       Tool 7.2 presents a map showing where trace element deficiencies (selenium and
disease
management
                cobalt) are most likely to occur in southern Australia.
plan
                Check that your herd is free of diseases by using Tool 7.3, an aid to diagnosing a
                number of common cattle diseases. Misdiagnosing a disease may result in
                substantial losses so consult with a veterinarian to confirm a diagnosis.




                    MLA More Beef from Pastures – Module 7: Herd health and welfare                  5
              Once you have identified the risk from any particular animal health issue, decide               Disease
              whether to:                                                                                     prevention is
                                                                                                              more effective
              • Take immediate action for prevention; or                                                      and less costly
                                                                                                              than treatment
              • Monitor the herd when disease symptoms are likely to occur in the production
                cycle, and act only when diseases appear.
              To help decide whether prevention of some of the more common recurring diseases
              (eg bloat, grass tetany and clostridial diseases) is cost-effective, a spreadsheet
              calculator (see Tool 7.4) can be used to do a simple partial budget. An example of a
              cost–benefit analysis for use of bloat capsules is presented in Tool 7.4.
              To decide whether to take action, know how severe a disease needs to become
              before it has an impact on production. Appropriate management strategies and/or
              corrective treatments for specific diseases are outlined in Tool 7.5.
              An example of monitoring is the use of faecal egg counts for internal parasites in
              young cattle (up to 12 months) to determine the need for drenching (see faecal egg
              counts box below).

               Use of faecal egg counts (FEC) to monitor internal parasites in cattle
Procedure 1




               In cattle production, internal parasites are an important management issue, particularly in
               stock up to 12 months of age and in more intensive management systems. Cattle younger
               than 12 months are best monitored by faecal egg counts. Cattle up to two years and
               older are also affected by gastrointestinal parasites, particularly under stress situations.

               The recommended approach is to implement an integrated parasite treatment and
               prevention program based on monitoring the faecal egg counts of young stock in
               conjunction with other key indicators such as growth rates and liveweight at first joining
               (Tool 7.5).

               The use of faecal egg counts in older cattle is unreliable, so base their treatment on the
               recommendations in Tools 7.1, 7.3 and 7.5.

               Timing of strategic drenching to prevent gastrointestinal parasites will vary slightly
               between regions and local conditions. MLA has developed The cattle parasite atlas: a
               regional guide to cattle parasite control in Australia, which presents an integrated
               approach to internal and external parasite control in various regions. It also contains
               basic information on the more important internal and external cattle parasites.

               Information on the role of faecal egg counts is also available from local veterinary
               practitioners, state departments of agriculture and their animal health websites.


              What to measure and when
              Individual diseases have different requirements as far as what to measure and when.
              Refer to the toolkit at the end of this module for more information on the following
              measurement aids:
              • Indicators of the conditions likely to lead to the development of common
                diseases of cattle (Tool 7.1);
              • Diagnostic tools to detect the presence of common diseases (Tool 7.3);
              • An understanding of the likely impact of a disease and how severe it needs to
                become to affect production;
              • Potential economic loss relative to cost of management and preventive
                treatment (Tool 7.4);
              • Market information on commodity prices to calculate cost–benefit budgets.


               6              MLA More Beef from Pastures – Module 7: Herd health and welfare
                    Procedure 2
                    Determine the risk and vaccinate to prevent specific
                    diseases


                    Guidelines for implementing a vaccination program
                    Vaccination is effective in preventing some common cattle diseases. Base the
                    decision to vaccinate on whether the potential loss is more than the cost of a
                    vaccination program, or if the disease poses a human health risk.
                    Identify the diseases that can infect cattle (and people) and can be vaccinated
                    against in your beef enterprise. These include:
                    • Clostridial diseases
                    • Vibriosis
                    • Trichomoniasis
                    • Leptospirosis
                    • Mucosal disease


Vaccinate           Seek local advice from your veterinarian or state department of agriculture. A




                                                                                                             Procedure 2
against
                    table to help determine the presence of these diseases treatable by vaccination is
specific
diseases if it is   presented in Tool 7.6.
cost-effective
or a human          If your enterprise is at risk of disease, determine whether a vaccination program
health risk         will be cost-effective. Tool 7.4 is a partial budget spreadsheet to help you
                    calculate this for bloat, grass tetany and clostridial diseases and Tool 7.7 lists
                    vaccines available for common cattle diseases. If you do have to vaccinate, the
                    timing of the treatment is important. The right times for vaccinating different
                    classes of cattle are presented in Tool 7.8.
                    Zoonotic diseases (those that affect both cattle and humans) are listed in Tool 7.9.
                    They include:
                    • Leptospirosis
                    • Q-fever
                    • Campylobacteriosis
                    • Milkers nodule
                    • Brucellosis
                    • Tuberculosis
                    • Cryptosporidiosis
                    • Yersiniosis




                      MLA More Beef from Pastures – Module 7: Herd health and welfare                    7
              • Salmonella
              • Listeriosis
              • Ringworm
              • Anthrax
              It is critical that a thorough risk assessment is conducted on the likelihood of you,   Assess the risk
              or anyone that may come into contact with your animals, contracting one of these        of cattle
              zoonotic diseases. If there is any risk at all, a vaccination program should be         diseases
                                                                                                      infecting
              implemented or a management system put in place that is guaranteed to prevent           people
              transmission of the disease.



              What to measure and when
              If you have not already done so, assess your beef enterprise’s current disease risk
              status then reassess whenever conditions that affect the disease occur, or the
              enterprise changes to include new or different classes of stock.
              The following should be monitored regularly:
              • The conditions likely to lead to the development of common cattle diseases
                (see Tool 7.7);
                                                                                                      Regularly
              • The presence of signs of disease treatable by vaccination (see Tool 7.6);             assess the
                                                                                                      disease status
              • The potential loss compared to the cost of a vaccination program (see Tool 7.4);      of your herd
Procedure 2




              • Recent cattle prices, to determine the cost-effectiveness of vaccination.
              Note: The timing of the vaccination for different classes of cattle is important
              (see Tool 7.8).




               8              MLA More Beef from Pastures – Module 7: Herd health and welfare
                   Procedure 3
                      Watch for sporadic diseases and disorders


                   Guidelines for managing sporadic diseases
                   Develop a routine to record details of diseased cattle or deaths whenever they
                   occur. You also need to decide how and where to keep a record of:
                   • When an animal is suspected of having a disease;
                   • When an animal has died;
                   • When an animal unexpectedly fails to meet a production target.


Keep records of    This is particularly important for large-herd operations where more than one stock
diseased cattle    person looks after the cattle. Records need to include the individual animal
and map areas
where deaths       identification, the mob or herd the animal belonged to, their immediate grazing
occur              history and all previous animal health treatments.
                   Animal identification tags and computer software programs for record-keeping are
                   commercially available.
                   Electronic tags make animals traceable when they leave the property and will
                   enable the installation of automated record-keeping systems to store information
                   electronically. This includes animal health records and production records such as
                   liveweights, calves weaned and other monitors of animal productivity.
Good records       You can implement any recognised quality assurance program based on keeping
are the basis of   good records and established veterinary codes of practice for cattle health and
quality
assurance          welfare. This may also provide access to new markets and/or better prices.
                   MLA has developed a Livestock Production Assurance program based on the cattle
                   National Vendor Declaration (NVD) Waybill. This is a key tool underpinning
                   Australia’s food safety reputation for cattle. Producers use the NVD to declare
                   valuable information about the food safety status of cattle being sold. An example
                   of the NVD Waybill for cattle, and instructions on how to fill in the sections, are
                   provided in Tool 7.10.
                                                                                                                     Procedure 3

                   Livestock Production Assurance program
                   When producers sign the National Vendor Declaration (NVD) Waybill, they will be declaring
                   that they meet the basic on-farm food safety requirements of the Livestock Production Assurance
                   program.
                   The Livestock Production Assurance program is a simple on-farm food safety program asking
                   producers to back up the information they provide on the NVD by keeping on-farm records.
                   The Livestock Production Assurance food safety requirements are outlined in five
                   elements, each having a ‘food safety outcome’ that relates to the NVD Waybill.
                   The main requirement is to be able to prove that on-farm practices meet these
                   food safety requirements.
                   Most producers will find that they already meet the Livestock Production
                   Assurance food safety outcomes and can prove this through current records.



                     MLA More Beef from Pastures – Module 7: Herd health and welfare                           9
                          Feedback from abattoirs can provide an early warning of the incidence of disease         Collect abattoir
                          in the herd. Where possible it is recommended that you collect abattoir feedback                feedback
                                                                                                                 whenever possible
                          whenever cattle are slaughtered.
                          If an uncommon or unexplained health problem occurs, seek professional advice             Seek veterinary
                          from your local veterinarian or state department of agriculture. In these cases your           advice for
                                                                                                                       unexplained
                          records provide crucial information. The state department animal health websites         health problems
                          are listed in Tool 7.10.
                          Regardless of the system used, you need to be aware of state and national codes of
                          practice. These are available on the government websites listed in Tool 7.11.


                          Also check that there are no toxic plants or contaminated feeds accessible to your
                          herd. A selection of references for the identification of toxic plants and noxious
                          weeds is included in Tool 7.12.


                                              IF YOU SUSPECT AN EXOTIC DISEASE,
                                         DIAL THE EMERGENCY ANIMAL DISEASE HOTLINE

                                                        1800 675 888
                          What to measure and when
                          Regularly observe your animals grazing at pasture and weigh them occasionally to
                          record:
Procedure 3 Procedure 2




                          • Pasture and animal condition score;
                          • Liveweight gain for comparison against that expected from the feed on offer
                            (FOO); and
                          • Cow breeding (reproductive) performance.
                          Note: you do not have to weigh every animal every time, a sample of about
                          10–20% is sufficient to estimate and monitor a mob’s liveweight gain or loss.


                          Also record:
                          • Any dead and/or diseased animals;
                          • Information on identification and/or management of noxious weeds and toxic
                            plants (see Tool 7.12);
                          • Information collected from abattoir feedback, whenever cattle are sold and this
                            information is available.




                          10              MLA More Beef from Pastures – Module 7: Herd health and welfare
                   Procedure 4

                      Prevent the introduction of infectious diseases


                   Guidelines for preventing the introduction of infectious diseases
                   The establishment of quarantine procedures for introduced stock is a
Quarantine         recommended practice to prevent the transfer of infectious diseases onto the farm.
introduced         The principles of quarantine and risk assessment need to be applied when
stock to prevent   introducing any new livestock onto the farm.
transfer of
infectious         Assess the risk of introducing an infectious disease before bringing new animals
diseases
                   onto the property. Tool 7.13 is designed to help assess the likely risk of
                   introducing diseases such as Bovine Johne’s Disease (BJD) and Mucosal disease
                   (bovine pestivirus) into a herd.

Check the          Local veterinarians or state departments of agriculture can also provide advice on
disease risk of    preventing the introduction of infectious diseases. It is worth the cost of a phone
all introduced     call to avoid introducing a serious disease into your herd. A diagnostic table (see
cattle
                   Tool 7.14) is also provided to assist with assessing the disease status of cattle
                   before being introduced into your disease-free herd. In principle:
                   • Only purchase stock known to be free of infectious diseases; and
                   • Where appropriate, quarantine all introduced animals until you are sure they
                     are disease-free.



Closed herds are   As an overall disease prevention strategy, implement a biosecurity plan for the
easier to          property by:
manage against
common             • Making sure the boundary and internal fences are stock proof;
production and
reproduction       • Quarantining all introduced cattle;
diseases
                   • Restricting use of yards and handling facilities to your own stock;
                   • Ensuring visitors’ vehicles remain in the house area.



                   What to measure and when
                   • Assess the risk of introducing infectious diseases into your herd. Tool 7.13
                                                                                                           Procedure 4



                     covers Bovine Johne’s Disease (BJD) and mucosal disease (bovine pestivirus).
                   • If there is a risk, know the symptoms of common diseases and carefully check
                     all cattle introduced onto the property (see Tool 7.14).
                   • If your herd contracts an infectious disease, take immediate action to prevent
                     the disease spreading (see Tool 7.15).




                     MLA More Beef from Pastures – Module 7: Herd health and welfare                  11
                                                                                                Toolkit 7
Toolkit 7

Tool 7.1 Conditions that exist for the
development of common cattle diseases

The table over the page will help you identify the conditions likely to influence the
development of the widespread diseases that can lead to significant economic loss
when left untreated or treatment is delayed, such as:
• Gastrointestinal parasites
• Liver fluke
• Grass tetany (hypomagnesemia)
• Milk fever (hypocalcaemia)
• Bloat
• Mineral deficiencies (copper, cobalt, selenium, phosphorus)
• Ketosis/pregnancy toxaemia


Important reproductive diseases include:
• Vibriosis
• Trichomoniasis
• Leptospirosis
• Bovine pestivirus or mucosal disease



Conditions that exist for the development of common cattle diseases
If suitable conditions exist for the development of disease on your farm,
management strategies should be adopted to prevent the listed diseases occurring.
                                                                                        Introduction




                               MLA More Beef from Pastures – Toolkit 7            1
Toolkit 7

                Disease                Conditions when likely to occur
                Gastrointestinal       High rainfall regions (>500mm annual rainfall), high
                parasites              risk above 600mm or irrigation.
                Such as:               High stocking rates, especially where high proportion of
                                       grazing pressure on property is cattle.
                Brown stomach
                worm (Ostertagia       Cattle less than 15 months of age: after weaning
                Ostertagi)             especially over winter and early spring period when
                                       peak larval challenge occurs.
                Trichostrongylus
                axei                   Rising 2–3 year-old cows: type 2 ostertagiasis in
                                       summer and autumn, especially in association with
                Cooperia spp           calving or nutritional stress.
                Haemonchus             Older cows: type 2 ostertagiasis less likely, but depends
                placei                 on property history.
                                       Bulls and bull beef systems are higher risk given their
                                       lower immunity to gastrointestinal parasites, (consider
                                       similar to cattle less than 15 months of age).
                                       If no effective control program in place clinical disease
                                       is highly likely in high rainfall areas.
                                       Intensification will exacerbate parasitism without
                                       adoption of proper prevention strategies, particularly in
                                       the case of bull beef production.



                Liver fluke            Previous history on property but there are many farms
                                       where infection is not recognised and is causing
                                       production losses. A blood test is required to detect
                                       antibodies in combination with faecal egg counts.
                                       Presence of fluke snail (L. tomentosa) on property.
                                       Stock have grazing access to springs, swampy areas,
                                       water courses and irrigation.
                                       Acute fluke disease: usually from early summer to late
                                       autumn.
                                       Chronic fluke: any time, but typically late summer to
                                       winter.
                                       If no effective control program in place clinical disease
                                       is more likely, especially in cattle less than 18 months
                                       of age. Animals suffering from liver fluke disease may
                                       not show any obvious symptoms and deaths account
                                       for only part of lost production in cattle. Other
                                       symptoms are associated with ill thrift and include
                                       reduced production and quality of milk, lower growth
                                       rates and lower feed conversion rates in growing cattle.




            2              MLA More Beef from Pastures – Toolkit 7
                                                                                   Toolkit 7
Grass tetany      Previous history on property.

(Hypomagnesemia   Usually older cows (>5 years old) mostly in first 3–4
–low magnesium)   months of lactation.
                  Grass dominant pasture from late autumn to early spring.
                  Pasture with high potassium or nitrogen content (or
                  application of potassium or nitrogenous fertiliser).
                  Short pasture (<1,000 kg DM/ha) at 1–2 leaf stage is more
                  likely to have elevated K/Mg ratio with higher grass tetany
                  risk, pasture potassium >35 gram/kg dry matter.
                  Pastures with low sodium intake (<2 gram/kg dry matter).
                  Pasture with low roughage intake (This leads to less
                  salivation and low sodium in rumen thus poor magnesium
                  absorption, in addition poor calcium uptake from bones
                  thus cow at higher risk of low hypomagnesemia.)
                  Cold wet weather that reduces cow feed intake.
                  Lactating cows held off feed (eg to mark calves) or cows in
                  oestrus.
                  Very fat >FS3.5 or very thin cows <FS2.
                  Increasing fertiliser application and pasture quality will
                  increase the risk of grass tetany.



Milk fever        Previous history on property.

(hypocalcaemia)   Usually older cows (>5 years old).
                  Usually late pregnancy (also after calving in dairy cows).
                  Usually high producing and dairy cross cows.
                  Previous history of cow with hypocalcaemia.

                  Alkaline diets (high Na+, K+ and low SO4= C1-).

                  Low calcium intake after calving (and high intake before).
                  Low roughage intake.
                  Fat cows > FS3.5


Bloat             Lush rapidly growing legumes. More likely with legume
                  pasture in rapidly growing vegetative stage, in highly
                  digestible pasture with low percentage of dry matter.
                  Highest risk lucerne > white clover > subterranean clover.
                  Intensive feeding ration (mainly in feedlot or drought
                  feeding) with low fibre component (>80% of ration as
                  grain).

                      MLA More Beef from Pastures – Toolkit 7                  3
Toolkit 7

            Mineral deficiencies:     Copper: known deficient regions such as coastal sandy
            Copper deficiency         soils, granite soils, peat swamps (Tool 7.2),
                                      exacerbated by excess molybdenum or lime
                                      application. Deficiency typically occurs after extended
                                      period of green feed, with copper more available in
                                      dry feed. Growing stock, breeding stock.



            Selenium deficiency       Selenium: known deficient regions such as coastal
                                      sandy soils, acidic soils, sedimentary and granite soils
                                      usually in high rainfall regions (Tool 7.2) exacerbated
                                      by high superphosphate application and clover
                                      dominance, typically deficiencies are greatest when
                                      feed is lush. Young growing stock.



            Cobalt                    Cobalt: known deficient regions such as coastal
            deficiency                calcareous sands, high rainfall granite soils and
                                      krasnozem soils (Tool 7.2), exacerbated by liming and
                                      high superphosphate application, especially in lush
                                      seasons. Young growing stock.



            Phosphorus                Phosphorus: history of very limited superphosphate
            deficiency                application on soils naturally deficient in phosphorus.
                                      Lactating cows and young growing cattle.
                                      Occurs if cattle consume <0.5g P/kg dry matter.



            Ketosis/pregnancy         Late pregnant cows in last six weeks of pregnancy
            toxaemia                  grazing dry poor quality pasture (<1,000–1,500kg
                                      DM/ha), stubbles or green pasture less than 800kg
                                      DM/ha. Either cows over fat score 3 or light cows on
                                      very poor pasture.



            Infectious                While some reproductive diseases have highly visible
            reproductive              consequences, such as late-term abortions, many work
            diseases:                 silently with the result unseen for weeks or months.
                                      Where, in the absence of a drought or a seasonal feed
                                      shortage situation, there has been a dramatic reduction
                                      in pregnancy rates, branding rate or weaning rates, or
                                      major changes in calving distribution patterns, then the
                                      producer should suspect that reproductive disease is
                                      present and arrange for veterinary investigations to be
                                      done. In the case of diseases like vibriosis and
                                      trichomoniasis, failure to investigate and act may mean
                                      that herd fertility could be lower in the following year
                                      as well.




            4            MLA More Beef from Pastures – Toolkit 7
                                                                                           Toolkit 7
Vibriosis               Vibriosis is a common venereal disease of cattle that is
(campylobacteriosis)    transmitted by mating infected bulls to susceptible cows.
                        Infected bulls or cows moving between or among herds
                        will spread the disease. It is caused by the bacteria
                        Campylobacter foetus, subspecies foetus. It is primarily a
                        problem in heifers, but can be a problem with older
                        cows not previously exposed and with no immunity.
                        Incidence increases with the age of the bull.



Trichomoniasis          Trichomoniasis is a venereal disease that causes
                        embryonic losses, vaginal discharges and abortions in
                        cows. It is caused by an organism called Tritrichomonas
                        foetus. It is transmitted by mating infected bulls to
                        susceptible cows. Similarly, an infected female may
                        infect any bull that serves her.



Leptospirosis           Leptospirosis is a common and contagious disease of
                        cattle. It is caused by an organism called leptospira.
                        Contamination of pasture, drinking water and feed via
                        infected urine of an infected animal is the main source
                        of disease spread. Members of the leptospira species are
                        divided into over 200 different types called serovars. It is
                        transmissible to humans, posing a work place health and
                        safety issue. In humans, it can cause serious, long-term
                        illness.


 Bovine                 Causes abortion, ill thrift in young calves, diarrhoea and
 Pestivirus             respiratory disease.
 known as
 Mucosal                Transmission is usually by direct contact with a carrier
 disease and            animal. The virus is common and if present in a herd
 Bovine viral           many animals will be exposed and show antibody titres.
 diarrhoea virus        The disease has its largest effect when it is introduced
 (BVD)                  into a susceptible herd of pregnant females.




 With all diseases and nutritional deficiencies, assess the risk based on
 previous local district history (seek information from local veterinarian,
 state government officers and local consultants) and if available property
 history.
 Intensification of the beef production system is likely to increase risk of
 diseases such as gastrointestinal parasitism, bloat and reproduction and
 exacerbate some trace mineral deficiencies (copper, selenium, cobalt).




                           MLA More Beef from Pastures – Toolkit 7                     5
Toolkit 7

            Tool 7.2 Distribution maps showing trace
            element and mineral deficiencies for
            southern Australia

            Trace elements
            This map highlights the main regions where trace element deficiencies occur (but
            does not necessarily cover all trace element deficient regions).


            Figure 1: Areas where livestock may be at risk from selenium deficiency or toxicity




            Source: Judson, GJ and Reuter, DJ ‘Selenium’, in KI Peverill, LA Sparrow and DJ
            Reuter (eds), Soil Analysis: An Interpretation Manual, Melbourne: CSIRO
            Publishing, 1999; 325–329.



            Further references
            Other reference material includes Hosking, WJ et al ‘Trace Elements for Pastures
            and Animals in Victoria’. Department of Agriculture and Rural Affairs.
            For details of Australia-wide deficiencies, refer to KI Peverill, LA Sparrow and DJ
            Reuter (eds), Soil Analysis: An Interpretation Manual, Melbourne: CSIRO
            Publishing, 1999.




             6            MLA More Beef from Pastures – Toolkit 7
                                                                                        Toolkit 7
Cobalt deficiency
Figure 2: Areas where livestock may be at risk from cobalt deficiency




                                             NORTHERN
                                             TERRITORY




                        WESTERN
                       AUSTRALIA                                       QUEENSLAND


                                                  SOUTH
                                                AUSTRALIA


                                                                        NEW
                                                                       SOUTH
                                                                       WALES



                                                                 VICTORIA


                        Areas at risk to Co deficiency


                                                            TASMANIA




Source: Peverill, KI and Judson, GJ ‘Cobalt’ in KI Peverill, LA Sparrow and DJ
Reuter (eds), Soil Analysis: An Interpretation Manual, Melbourne: CSIRO
Publishing, 1999;319–323.



Mineral deficiencies
More specific state details can be found on state department of agriculture
websites:
• New South Wales                  www.agric.nsw.gov.au
• Victoria                         www.dpi.vic.gov.au
• South Australia                  www.sardi.sa.gov.au
                                   www.pir.sa.gov.au
• Western Australia                www.agric.wa.gov.au
• Tasmania                         www.dpiwe.tas.gov.au




                               MLA More Beef from Pastures – Toolkit 7              7
Toolkit 7

            Tool 7.3 Diagnostic tool for common
            diseases
            The following table aids the diagnosis of the diseases listed in Tool 7.1. It is
            recommended producers consult a veterinarian to confirm disease diagnosis.



                Gastrointestinal         Diagnostic tool
                parasites
                                         History: poor performance on pasture (growth rates of
                                         different classes of cattle is less than expected with
                                         known pasture availability and quality).
                                         Clinical signs: scouring, weight loss, bottle jaw.
                                         Autopsy: high total worm counts.
                                         Faecal egg counts: some value in stock less than 12
                                         months old.
                                         Blood: Serum pepsinogen: indicates gut damage from
                                         immature worms.
                                         Field trials to assess growth response from drenching can
                                         be very useful if uncertain of parasitological and
                                         economic benefit, particularly in regions where
                                         gastrointestinal parasites are not considered to be
                                         economically important.


                Liver fluke              History on property, individual paddock.
                                         Clinical signs: bottle jaw, scouring weight loss.
                                         Autopsy: fluke in liver.
                                         Blood biochemistry: Liver enzyme – evidence of
                                         immature fluke causing damage to liver.
                                         Faecal egg counts indicate presence of adult fluke – most
                                         valuable in young animals.
                                         Blood: Serum ELISA for mob diagnosis (the most sensitive
                                         test to detect presence of disease on a farm).
                                         Abattoir surveillance and feedback on prevalence of liver
                                         fluke.


              Grass tetany               Clinical signs: hyper-excitable, thrashing convulsions if
                                         recumbent.
                                         Respond to treatment magnesium hypophosphite (5%),
                                         calcium borogluconate (25%) 500ml or 200ml 50%
                                         magnesium sulphate intravenously.



            8                 MLA More Beef from Pastures – Toolkit 7
                                                                                    Toolkit 7
Grass tetany   When alive:
               Blood: plasma magnesium <0.6mmol/l.
               Undetectable Mg in urine.
               Concurrent hypocalcaemia – low calcium (plasma Ca
               <2.0mmol/l.
               Post mortem:
               Eye vitreous humor Mg <0.4mmol/l.
               Pasture assessment (availability, quality) and stock fat
               score assessment to assess risk of cows to grass tetany
               (fat lactating cows with rapid weight loss are at high risk.
               Pasture leaf tissue test to evaluate mineral balance.
               Soil analysis usually not a good indicator of grass tetany
               risk.


Milk fever     Clinical signs of tetany, unable to rise, dry muzzle either
               just about to calve or recently calved.
               Respond to treatment with calcium borogluconate with
               a dose of 8–14g of calcium.
               Blood: plasma calcium <1.5mmol Ca/l.
               Complicated with hypomagnesemia (see above) and
               calving paralysis.


Bloat          Clinical signs (mob not just individual): sudden death,
               distension in the left upper flank if still alive or others in
               mob with mild signs.
               Autopsy: non-specific, congestion and engorgement of
               tongue, congestion of forequarters.
               Pasture assessment (proportion of legume in pasture is
               high, lush and in vegetative growth). May develop bloat
               in less than one hour after introduction to a paddock but
               often after a day.


Mineral        Copper deficiency: Biopsy: Liver copper most sensitive
deficiencies   deficient <0.1mmol/kg DM
               Blood biochemistry: Plasma copper deficient <5µmol/l,
               ceruloplasmin deficient <5 U/l.
               Pasture: assay copper, molybdenum, sulphate to
               determine if other factors are interacting to cause



                 MLA More Beef from Pastures – Toolkit 7                        9
Toolkit 7

             Mineral                deficiency or copper alone. Adequate pasture copper
             deficiencies           >7mg/kg DM, note that available copper is reduced by
                                    50% for every increase of 4mg molybdenum/kg DM.
                                    Seek advice from your veterinarian for more
                                    complicated interactions.
                                    Soil: copper poorly correlated with animal status, so do
                                    not use soils test to assess animal copper status.
                                    Abattoir: collection of liver samples if field biopsy not
                                    possible.
                                    Clinical signs: rough coat, sandy colour Herefords or
                                    bronze tinged Angus colour poor growth, diarrhoea.
                                    Clinical response trial comparing response to treatment
                                    with either copper injection or copper capsules to
                                    untreated control animals most definitive.
                                    Selenium deficiency: Blood biochemistry: blood
                                    glutathione peroxidase deficient <10 units, blood
                                    selenium deficient <0.25µmol/l, liver selenium <2.5
                                    nmol/kg DM and pasture selenium deficient <0.02
                                    mg/kg DM.
                                    Clinical signs: stiff-legged gait, sudden death, poor
                                    growth an uncommon sign.
                                    Clinical response trial comparing response to treatment
                                    with either oral selenium drench or selenium pellets to
                                    untreated control animals.
                                    Cobalt deficiency: Blood biochemistry: plasma vitamin
                                    B12 deficient <0.1mmol/l, liver vitamin B12 deficient
                                    <75 nmol/kg wet weight, liver cobalt deficient
                                    <1.0µmol/kg dry matter and pasture cobalt deficient
                                    <0.1 mg/kg DM.
                                    Clinical signs: are similar to malnutrition, emaciation,
                                    ill-thrift has been associated with a high degree of
                                    ketosis and poor body condition.
                                    Clinical response trial comparing response to treatment
                                    with either vitamin B12 injection or cobalt pellets to
                                    untreated control animals.
                                    Phosphorus deficiency: Clinical signs: Pica (eating
                                    bones and other rubbish), poor growth, soft bones and
                                    bone fractures, infertility, post calving red water.
                                    Biochemistry: deficient soil 0.002%, pasture deficient
                                    <0.2% intake required ideally above 40–50gram/day
                                    phosphorus for mature cattle.




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Ketosis/pregnancy       Clinical signs: pregnant, recumbent or neurological signs
toxaemia                such as staggering, aggression, delirium. Often associated
                        disease process.
                        Blood: biochemistry analysis of ß–OH Butyrate normal is
                        less than 0.8mmol/l, blood glucose reduced to 20–40
                        mg/dl, urine ketones are high on urine dipstick.



 Infectious             The following observations can assist in identifying the
 reproductive           presence of reproductive diseases:
 diseases               • Early term abortion (pestivirus, vibriosis and
                          trichomoniasis).
                        • Late term abortion (leptospirosis and neosporosis).
                        • Extended breeding season (vibriosis).
                        • Low calving rates (vibriosis).
                        • Temporary infertility (pestivirus).
                        • Decline in quantity and quality of milk (leptospirosis).
                        • Early embryonic death (pestivirus and vibriosis).
                        • Immune suppression (pestivirus).
                        • Neurological damage (pestivirus).
                        • Weak, stunted or deformed calves (pestivirus and
                          leptospirosis).
                        • Persistent infection (pestivirus).
                        • Bloody, port-wine coloured urine (leptospirosis).
                        • Rough, dry hair coat (leptospirosis).
                        Note: Considerable losses experienced from abortions
                        should be reported to your state department of agriculture.


  The diagnosis of most diseases listed is likely to require advice and
  assistance from your veterinarian




                          MLA More Beef from Pastures – Toolkit 7                  11
Toolkit 7

            Tool 7.4 Decision support spreadsheet to
            determine cost-effectiveness of common
            preventative treatments
            A ‘Health cost benefit calculator’ is provided on the enclosed CD-ROM. The
            calculator has been developed to help you work out the benefit of applying an
            animal health treatment to your herd for bloat, clostridial diseases and grass tetany.




            12            MLA More Beef from Pastures – Toolkit 7
                                                                                           Toolkit 7
Tool 7.5 Management strategies to
prevent disease

This table presents key management strategies to be adopted to prevent specific
diseases.



  Disease                 Management strategy to prevent disease
                          Timing of strategic drenching to prevent gastrointestinal
  Gastrointestinal
                          parasites will vary slightly between regions and local
  parasites
                          conditions. Timing of treatment is critical with younger
                          cattle likely to require additional treatments.
  Such as:
  Brown stomach           Strategic drenching: (Refer to MLA’s Cattle Parasite Atlas
  worm                    for basic information on the more important internal and
  Trichostrongylus        external cattle parasites and an integrated approach to
  axei                    internal/external parasite control in various regions).
  Cooperia spp               • Calves at weaning in all risk situations
  Haemonchus
                             • May/June (>500–600 mm rainfall)
  placei
                                – 17 months of age for summer drop calves
                                – 14 months for autumn drop
                                – 11 months for winter drop
                                – 8 months for spring drop
                             • July/August (>500–600 mm rainfall)
                                – 10–13 months for winter–spring drop
                             • Rising 2 and 3-year-old cows, all bulls in summer
                          Other drenches:
                             • Based on diagnostic Tool 2
                          Grazing management:
                          Graze weaners on pastures with low worm larvae
                          contamination.
                             • Low worm risk pastures include:
                                – new pasture or fodder crop
                                – pasture grazed by sheep for last 6 months
                             • moderate worm risk pastures include:
                                – pasture grazed by mature dry cattle
                             • high worm risk pastures include:
                                – pasture grazed by young wormy cattle
                          Introducing new stock:
                             • Drench with a macrocyclic lactone (ML) on arrival.
                          Observe withholding periods and export slaughter
                          intervals of anthelmintic treatments. These are available
                          at www.mla.com.au/esi

                            MLA More Beef from Pastures – Toolkit 7                   13
Toolkit 7

                                       Macrocyclic lactones (ML) are generally the most
                                       commonly-used drench type due to high efficacy and
                                       persistent activity. Benzimidazoles (BZ) are very useful
                                       and are cheaper, although they have to be given by
                                       mouth. In situations of high and ongoing larval
                                       challenge with stock less than 18 months-old, persistent
                                       MLs are more desirable. Based on evidence overseas it
                                       is likely that anthelmintic resistance is likely to develop
                                       with cattle gastrointestinal parasites to both BZ and ML
                                       drenches. This is most likely in bull beef enterprises
                                       where more regular drenching is likely. Drench efficacy
                                       testing should be undertaken as part of normal
                                       management.


             Liver fluke               Chronic fluke:
                                          • Strategic: drenching with Triclabendazole in late
                                            autumn and early winter to kill all fluke picked up
                                            over summer and autumn. Early spring treatment
                                            to remove adult infections missed by the
                                            autumn/winter treatment. This will prevent
                                            contamination of snail habitats for the next year.
                                            Other cheaper chemicals can be used for this
                                            treatment including injectable products. Late
                                            summer drench may also be required in high-risk
                                            situations or where monitoring indicates the
                                            presence of infection, particularly with animal less
                                            than 15 months.
                                       Acute fluke:
                                          • Early drenching with triclabendazole may be
                                            required.
                                       New stock:
                                          • Drench with triclabendazole if risk assessment
                                            indicates likely infection.


                 Grass tetany          Increase Mg intake to at risk group of cows:
                 (hypomagnesemia)         • Feeding 60 grams MgO/day (causmag) on hay
                                            during at-risk periods.
                                          • Intra-ruminal bullets provide Mg for up to 90 days.
                                          • Feed hay (also source of calcium).
                                          • Ensure constant access to feed.
                                       Avoid high-risk pastures (high potassium due to K or N
                                       application or short pasture in 1–2 leaf stage) or pastures
                                       where cows have a history of grass tetany. K intake
                                       levels are minimised when plants are grazed at the 3–4
                                       leaf stage.
                                       If grass tetany still a problem:
                                          • Consider licks with equal portions of fine
                                            limestone:salt:causmag mixed with molasses. For

            14             MLA More Beef from Pastures – Toolkit 7
                                                                                           Toolkit 7
Grass tetany            success it is important that cattle are trained on to these
                        licks initially with molasses.
(hypomagnesemia)
                        See Tool 7.4 for cost benefit of control options.
                        Lower herd age structure (See Module 6: Weaner
                        throughput) as older cows are high risk.
                        Autumn calving herds change time of calving to spring
                        to reduce period of risk. This will not eliminate the risk
                        of grass tetany but reduce the period where prevention is
                        required. This decision should be considered with other
                        management procedures.
                        Treat affected cows with subcutaneous injection of Mg
                        hypophosphite (5%), calcium borogluconate (25%) –
                        500ml or 200ml of 50% Mg sulphate. Seek veterinary
                        advice.


Milk fever              Avoid over-fat cows: FS<3.5
(hypocalcaemia)         Ensure constant access to feed during calving and avoid
                        grazing high-risk pastures (as for grass tetany).
                        Feed hay after calving (consider cost benefit) avoid hay
                        before calving.
                        Keep calcium intake less than 50g/day before calving.
                        Prevent hypomagnesemia.
                        Lower herd age structure as older cows are higher risk.


Bloat                   Avoid grazing high-risk pasture with a high proportion of
                        actively growing legumes in vegetative growth by use of
                        grazing management.
                        For producers adopting intensive rotational grazing
                        slowing rotation so cattle graze more mature pasture
                        may reduce risk but not eliminate it in all situations.
                        In intensive grazing/strip grazing situations, daily
                        spraying bloat oil on pasture may be cost effective. This
                        strategy will not be cost effective or practical in all other
                        situations. Bloat oil in water troughs may be considered
                        if water availability is controlled. Bloat blocks are less
                        reliable.
                        Use bloat capsule if grazing high risk pastures for
                        extended period. See Tool 7.4 for cost benefit of bloat
                        capsule.
                        Consider incorporating blat resistant legumes, such as
                        Lotus corniculatis, into pasture mixes.

Mineral deficiencies:
Copper deficiency       Copper injection before any high risk periods of winter
                        and spring or copper capsules to provide longer-term (12
                        months) prevention.


                           MLA More Beef from Pastures – Toolkit 7                    15
Toolkit 7

                                     Top dress pasture periodically (usually 5–7 years) if
                                     copper in herbage low.
                                     When applying molybdenum to pasture add copper if
                                     copper marginal in herbage. Discuss dosage and
                                     options with your veterinarian and agronomist.


             Selenium deficiency     Oral selenium drench (sodium selenite/sodium
                                     selenate) at 0.1mg Se/kg body weight for immediate
                                     treatment of animals giving 6–8 weeks protection.
                                     Selenium pour-on convenient and will protect for 3
                                     months.
                                     Selenium pellets or injection for longer-term
                                     protection.
                                     Top-dress pasture (depends on cost/benefit), usually
                                     too expensive, except in high stocking rate situations.
                                     Discuss dosage and options with your veterinarian
                                     and agronomist.


             Cobalt deficiency       Vitamin B12 injection (8–12 weeks prevention) or
                                     cobalt pellets for longer term prevention.
                                     Top-dress pasture (variable response).
                                     Discuss dosage and options with your veterinarian
                                     and agronomist.


             Phosphorus              Best long-term solution is to top-dress pasture with
             deficiency              superphosphate.
                                     Lick with dicalcium phosphate mix with salt and
                                     molasses (care with superphosphate licks because of
                                     risk of fluoride toxicity).
                                     Sodium acid phosphate injection for acute deficiency.


             Ketosis/pregnancy       Avoid grazing cows on pasture where rapid weight
             toxaemia                loss is likely in late pregnancy, or supplement to avoid
                                     rapid weight loss.
                                     Avoid getting cows too fat (>FS3.5–4) or too thin
                                     (<FS2–2.5) in late pregnancy.


             Reproductive
             diseases:
             Vibriosis               Where security of paddocks is maintained annual
                                     vaccination of bulls can give adequate herd protection
                                     (preferable approach for extensive herds).
                                     Where cattle security cannot be maintained, initially
                                     all breeding cattle in the herd should be vaccinated.
                                     Thereafter, the most cost effective approach is to
                                     vaccinate all replacement heifers and bulls annually.

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                      Culling all empty breeders at a pregnancy test will greatly
                      reduce the prevalence of the disease, but pregnant
                      animals may still be carriers of the disease.
                      All introduced bulls should be vaccinated.
                      Reducing the age of bulls (to less than seven years), bull
                      control and seasonal mating also facilitates disease
                      control.


Trichonomiasis        No commercial vaccine is available.
                      Heifer segregation and mating with young bulls is one
                      possible control strategy.
                      Controlled mating, ie restricting mating to a short (3–6-
                      month) period providing sexual rest of cows.
                      Cull infected bulls.
                      Reducing the age of bulls, bull control and seasonal
                      mating also facilitates disease control.


Mucosal disease       A vaccine is now available to control the disease.
(bovine pestivirus)   Ensure replacement heifers develop a strong immunity
                      before joining.


With all diseases and deficiencies seek advice on appropriate short-term
treatments and long-term prevention strategies.




                          MLA More Beef from Pastures – Toolkit 7                  17
Toolkit 7

            Tool 7.6 Diagnostic tool to detect
            presence of diseases
            This table lists tools used to assist the diagnosis of the diseases treated by
            vaccination.


               Disease                  Diagnostic tool

               Clostridial diseases     Clinical signs:
                                        Tetanus: convulsions initially stimulated by sound or
                                        touch and gradually progress in severity.
                                        Black leg: severe lameness, swelling on affected leg,
                                        very depressed, fever, skin dry and cracked, often
                                        sudden death.
                                        Black disease: profound depression and abdominal
                                        pain, sudden death.
                                        Malignant oedema: contaminated wound often
                                        associated with calving, local swelling, fever, severe
                                        toxaemia and death.
                                        Pulpy Kidney: convulsions, sudden death.


                                        With all clostridial diseases veterinary assistance will
                                        be required to assist in diagnosis with autopsy,
                                        bacteriology and histopathology.


               Vibriosis                Clinical signs: usually early embryonic death shows
                                        up as early return to service, spread out calving and
                                        very poor pregnancy rates (often less than 50%
                                        pregnancy). Will affect all age groups if recently
                                        introduced or heifers mostly affected in herds where
                                        disease is endemic.
                                        Preputial scrapings: under instruction from
                                        veterinarian, scrapings taken from the prepuce of a
                                        bull for bacterial culture.
                                        Vaginal swab: detect antigen (mob test) with vaginal
                                        mucous ELISA test through your veterinarian.


               Trichomoniasis           Diagnosis through laboratory testing of vaginal
                                        discharge from cows and from preputial scrapings
                                        from bulls.


               Leptospirosis            Clinical signs: abortion (consider other causes) or
                                        stillborn calves, occasionally mastitis.
                                        Aborted foetus: Bacteriological isolation of organism.
                                        Cows: paired bloods for serological testing on both
                                        affected and unaffected cows.


            18             MLA More Beef from Pastures – Toolkit 7
                                                                                      Toolkit 7
                        Calves: Red urine severe fever, death; bacteriological
                        isolation of organism.


Mucosal disease         Clinical signs: wide range of signs depending on strain
(bovine pestivirus)     of virus and time of infection. Can vary from mild
                        diarrhoea to chronic ill-thrift and wastage in cattle up
                        to 18 months to sudden death of cattle between 6
                        months and 2 years of age.
                        Serological testing for presence of antibody and testing
                        of serologically negative cattle for presence of virus
                        (antigen).
                        The diagnosis of mucosal disease will require
                        veterinary input to assist in diagnosis with autopsy,
                        serological testing and histopathology.


The diagnosis of most diseases listed is likely to require advice and assistance
from your veterinarian.




                          MLA More Beef from Pastures – Toolkit 7                19
Toolkit 7

            Tool 7.7 Conditions and vaccines for
            prevention of common cattle diseases
            Vaccines include:
             • Clostridial vaccines prevent mortality against black leg, black disease, tetanus,
               pulpy kidney and malignant oedema.
             • Vibriovax™ protects against campylobacter infection in breeding cows that can
               cause infertility and abortion.
             • Leptospirosis vaccine protects against abortion, calf deaths and reduces
               shedding of leptospira bacterium and consequently the risk of human infection.
             • Pestigard™ vaccine prevents reproductive wastage and mortalities caused by
               pestivirus or mucosal disease.


            This table is used to help identify conditions and vaccines used to prevent the
            development of common diseases that can lead to significant economic loss when
            left untreated.


             Disease            Conditions when likely to occur                 Vaccine


             Clostridial
             diseases:
              • Tetanus         – Penetrating wound including marking           Ultravac 5in1™
                                  wounds
                                                                                Websters 5in1
                                                                                vaccine for cattle
                                – Muscle bruising, growing animals              and sheep™
             • Black leg
                                                                                Websters 5in1
                                                                                vaccine with
             • Black            – Liver fluke infestation
                                                                                vitamin B12 for
               disease                                                          cattle and sheep™
              • Malignant       – Wounds                                        Websters low
                oedema                                                          volume 5in1
              • Pulpy           – Lush pasture, heavy grain feeding,            vaccine for cattle
                Kidney            change feed                                   and sheep™
                                With all clostridial disease consider the       Tasvax 5in1™
                                local risk based on previous local district
                                history and if available property history.
                                Intensification is likely to increase risk of
                                clostridial diseases such as blackleg or
                                pulpy kidney.


             Vibriosis          Venereal infection, likely to occur when        Vibriovax™
                                cattle (bulls, mated heifers, cows)
                                introduced to breeding herd, particularly
                                from unknown origin.



            20             MLA More Beef from Pastures – Toolkit 7
                                                                                   Toolkit 7
Leptospirosis   Imported cattle or neighbouring cattle       Cattlevax LC
                likely to introduce disease.                 7in1™
                Properties trading cattle in conjunction     Leptoshield™
                with a breeding herd are at higher risk.     Leptovax™
                Cattle have contact with wildlife            Ultravac 7in1™
                reservoirs such as feral pigs.
                                                             Websters
                Previous history of leptospirosis in herd.   Clepto-7™
                Cattle have access to wet areas where        Websters HP
                leptospirosis bacteria survives.             vaccine for
                Farm workers and veterinarians will be       cattle™
                at risk if handling cattle shedding
                bacterium.


Mucosal         Close contact between cattle.                Pestigard
disease         Cattle shedding virus introduced to          Vaccine™
(bovine         herd, or persistently infected cattle
pestivirus)     already present in herd infect
                susceptible cattle in early pregnancy.
                Breeding herds are most at risk if other
                cattle are brought onto property or they
                have access to other cattle.




                           MLA More Beef from Pastures – Toolkit 7            21
Toolkit 7

            Tool 7.8 Vaccination strategies
            This table outlines the appropriate timing of vaccination to prevent production
            diseases and economic loss.




              Vaccine                  Strategy
              Clostridial vaccine      For maximum protection of young calves:
                                         • Vaccinate cow 2–6 weeks before calving.
                                       For protection of calves from unvaccinated cows:
                                         • Vaccinate early and a booster 4–8 weeks later.
                                       For protection of calves from vaccinated cows:
                                         • Vaccinate calves at 6–8 months and booster
                                           4–8 weeks later.
                                       Older stock:
                                         • Annual booster timed before high-risk period or
                                           more frequently in high-risk situation, such as
                                           grain feeding in drought.
                                       New stock
                                         • Implement vaccination procedures as for normal
                                           stock. If history of vaccination known,
                                           implement herd program. If vaccination history
                                           not known, give a sensitising dose then booster
                                           4–8 weeks later.


              Vibriosis                Bulls:
                                         • Initially 2 doses at least 4 weeks apart when
                                           bulls first introduced onto property and then an
                                           annual booster.
                                       Females:
                                         • Not routinely, use only if presence of infection
                                           confirmed by your veterinarian.


              Leptospirosis            Calves:
                                         • A priming dose administered at a minimum of 4
                                           weeks of age.
                                         • Booster dose 4–6 weeks later.
                                       Older stock
                                         • Annual booster timed prior to season of greatest
                                           risk (when conditions are wet) or cows 4–6
                                           weeks before calving.
                                       Leptospirosis vaccine usually given in conjunction
                                       with clostridial vaccines.



            22            MLA More Beef from Pastures – Toolkit 7
                                                                                      Toolkit 7
                          New stock
                            • Consider risk of introduction of infection.
                              Implement herd vaccination program if new
                              stock have previously been vaccinated. If
                              history not known, give a priming dose then a
                              booster 4–6 weeks later.


  Mucosal disease         Bulls
  (bovine pestivirus)       • Two doses 4–6 weeks apart with annual boosters
                              thereafter. Must be given before breeding.
                          Females:
                            • Two doses 4–6 weeks apart with annual boosters
                              thereafter. Must be given before breeding for
                              foetal protection to occur.
                          Management
                            • Identify persistently infected cattle in conjunction
                              with your veterinarian and remove from herd.
                          Minimise risk of exposure (avoid exposing breeding
                          herd to outside cattle – see Procedure 4 for guidelines
                          for preventing the introduction of infectious diseases).




Important considerations when vaccinating cattle:
 • Follow the manufacturer’s instructions closely.
 • Store and handle vaccines correctly to ensure the effectiveness of the vaccine
   is not reduced.
 • Carefully adhere to safety precautions for workers handling vaccines and
   associated equipment.
 • Dispose of used equipment safely, avoiding environmental contamination.
 • To optimise the immunity gained ensure animals are in good health.
 • Full protection does not occur until up to four weeks after the initial doses of
   the vaccine.


Note: The information contained in these pages is intended as a general guide only.
Always obtain professional advice about your specific situation.




                            MLA More Beef from Pastures – Toolkit 7              23
Toolkit 7

            Tool 7.9 Zoonotic diseases of cattle
            This table list outlines diseases that infect cattle and can also infect people.


             Disease                  How spread                       Common signs in people


             Leptospirosis            Urine contamination with         Headache, chills, fever,
                                      skin or mucosal surface          muscle pain malaise,
                                                                       inflamed throat/pharynx


             Q-fever                  Inhalation of aerosols and       Headache, chills, fever,
                                      dust                             muscle pain malaise,
                                                                       coughing, vomiting


             Campylobacteriosis       Ingestion of contaminated        Severe diarrhoea, pain,
                                      food or water                    fever, headache, nausea


             Milkers nodule           Handling teats of cows or        Initially dark papule that
                                      mouths of calves                 heals spontaneously


             Brucellosis              From aborted foetus,             One case in Victoria in
                                      faeces, raw flesh or             2001; undulant fever
                                      bacteria in unpasteurised        aches, pains
                                      dairy products penetrates
                                      skin conjunctiva
                                      respiratory or gut

             Tuberculosis             Eradicated from Australia        Chronic cough, fever,
                                                                       weight loss


             Cryptosporidiosis        Faeco-oral route                 Mild watery diarrhoea


             Yersiniosis              Faeco-oral route                 Acute watery diarrhoea,
                                                                       fever, headache


             Salmonella               Faeco-oral route                 Acute watery/blood flecks
                                                                       diarrhoea, fever, headache


             Listeriosis              Food-borne disease,              Transient mild flu-like to
                                      especially chilled foods         acute eningoencephalitis
                                                                       with case fatality rate of
                                                                       30%, foetal infection can
                                                                       lead to abortion




            24              MLA More Beef from Pastures – Toolkit 7
                                                                                     Toolkit 7
 Ringworm               Direct contact with skin or   Dry, reddened skin, hair
                        from cattle handling          loss, inflamed skin
                        equipment


 Anthrax                Respiratory, ingestion or     Respiratory or gastro
                        local through break in skin   intestinal forms has a very
                                                      high mortality rate as
                                                      does local skin infection if
                                                      left untreated




Note: With all diseases or suspected disease outbreaks seek medical advice
immediately.




                            MLA More Beef from Pastures – Toolkit 7            25
Toolkit 7

            Tool 7.10 National Vendor Declaration
            (NVD) Waybill for cattle




            Further information
            Meat & Livestock Australia Tip & Tool OFS01: ‘National Vendor Declaration for
            Cattle’, provides information and a worked example of the National Vendor
            Declaration (NVD) Waybill for cattle to meet the food safety requirements of the
            Livestock Production Assurance program. To obtain a copy phone 1800 023 100,
            or visit www.mla.com.au/nvd


            26            MLA More Beef from Pastures – Toolkit 7
                                                                                     Toolkit 7
Tool 7.11 Disease information sources
Credible sources of disease information include:
  • Private veterinarians and consultants
  • State departments of agriculture and other government bodies.


Lists of state and national Codes of Practice are available on websites. The Codes
of Practice should be followed as part of normal cattle husbandry and welfare
management.


List of websites:
Australian Animal Health                              www.aahc.com.au
NSW Agriculture                                       www.agric.nsw.gov.au
Department of Primary Industries, Victoria            www.dpi.vic.gov.au
South Australia Research & Development Institute      www.sardi.sa.gov.au
Primary Industries South Australia                    www.pirsa.sa.gov.au
Department Primary Industries, Water & Environment,
Tasmania                                              www.dpiwe.tas.gov.au
Department of Agriculture Western Australia           www.agric.wa.gov.au


Further information
Reference material such as:
  • ‘Diseases of Livestock’ by TG Hungerford
  • ‘Stock Diseases’ by A Brightling (Inkata Press)




                              MLA More Beef from Pastures – Toolkit 7           27
Toolkit 7

            Tool 7.12 References to identification of
            toxic plants and noxious weeds
            Information on toxic plants and noxious weeds is available through the websites
            listed below. For further identification and management of toxic plants and
            noxious weeds consult your local private veterinarian or consultant or relevant
            state government authority.


            List of websites:
            Australian Animal Health                            www.aahc.com.au
            NSW Agriculture                                     www.agric.nsw.gov.au
            Department of Primary Industries, Victoria          www.dpi.vic.gov.au
            South Australia Research & Development Institute    www.sardi.sa.gov.au
            Primary Industries South Australia                  www.pirsa.sa.gov.au
            Department Primary Industries, Water & Environment,
            Tasmania                                            www.dpiwe.tas.gov.au
            Department of Agriculture Western Australia         www.agric.wa.gov.au


            Further information
              • ‘Poisonous Plants of Australia’ by S Everist (Angus & Robertson)
              • ‘Poisonous Plants: A handbook for farmers and graziers’ EJ McBarron
                (Inkata press)
              • ‘Medical and veterinary aspects of plant poisoning in New South Wales’ EJ
                McBarron (NSW Agriculture)




            28            MLA More Beef from Pastures – Toolkit 7
                                                                                      Toolkit 7
Tool 7.13 Disease risk assessment
protocols
The table below is designed to help assess the likely risk of introducing the
infectious diseases Bovine Johne’s Disease (BJD) and mucosal disease (bovine
pestivirus) into a beef herd.


  Disease                 Risk assessment
  Bovine Johne’s          • Purchase cattle from low-risk zones: Free and
  Disease                   Protected (maps for these available on websites
  (BJD)                     from state departments of agriculture and Animal
                            Health Australia)
                          • In Control and Residual Zones, BJD is common in
                            dairy herds but very uncommon in beef herds that
                            have had little or no contact with dairy cattle.
                            Assess risk more carefully when introducing cattle.
                          • Observe regulations with regards to the movement
                            of cattle between BJD zones and states.
                          • Market Assurance Program (CattleMAP) – highest
                            level QA program for BJD assurance. MN3 is
                            highest assurance>MN2>MN1. Details of MAP
                            herds on Animal Health Australia website
                            www.aahc.com.au.
                          • Beef Cattle Trade Assurance Scheme (BC-TAS) –
                            Beef Only herds that also undertake negative
                            check testing (see below). The testing requirement
                            is two Check Tests, two years apart. Testing and
                            assessment by an approved veterinarian.
                          • Check Test – In non-MAP herds with no
                            suspicion of infection, it is possible to undertake a
                            low level assurance test on selected adult animals
                            in the herd aimed at increasing the probability of
                            detecting infection. The Check Test requires 50
                            adults to be tested or all adults over 2 years if less
                            than 50 in herd. The Check Test is valid for 12
                            months valid in and only used to support a Vendor
                            Declaration of animals bred in that herd or to
                            animals introduced with a vendor declaration as
                            originating from Check Tested or higher status
                            herd.
                          • Beef Only – a new trade assurance classification,
                            based on the low prevalence of BJD in the pure
                            beef sector and on herd biosecurity to protect that
                            status. Facilitates the movement of low risk beef
                            cattle. Herds classified as infected, suspect or
                            restricted for BJD are not eligible. Eligible herds
                            must have had no contact with dairy herds for 5
                            years unless those herds were involved in the



                            MLA More Beef from Pastures – Toolkit 7              29
Toolkit 7

                                          CattleMAP (see Animal Health Statement from
                                          department of agriculture, etc.), only introduce
                                          cattle from a herd with the same or higher BJD
                                          status and introduce cattle with an approved
                                          animal health statement issued by the
                                          owner/person in charge of the animals.
                                       • On-farm quarantine: not practical given long time
                                         delay for development of disease and low
                                         sensitivity of tests in individual cattle. Only
                                         introduce cattle to property if they are at a similar
                                         or higher status.


              Mucosal disease          • For property that is sero negative, only buy from
              (bovine pestivirus)        sero negative herd. If this is not practical consider
                                         vaccination (cost benefit) or exposure of breeding
                                         animals well before joining to an known virus
                                         shedding animal.
                                       • Purchase cattle from property with no history of
                                         trading, agistment or cattle turnover, compared
                                         with cattle from cattle trading property or where
                                         agistment enterprise is run. (Purchase of cattle
                                         from closed herd is a lower risk).
                                       • Introducing any cattle to a closed breeding herd is
                                         high risk where the breeding herd may be naïve
                                         (haven’t been exposed to virus).
                                       • Introducing new cattle to a breeding herd in the
                                         early stages of pregnancy is a high risk.
                                       • Quarantine: If purchasing new cattle, keep in
                                         isolation, not in direct contact with breeding cows
                                         if breeding cows are pregnant (especially before
                                         day 150–180 gestation).


             When conducting a risk assessment it is important to consider the individual
             property circumstances. For example, if trading cattle is an important
             component of an enterprise and there is no risk to a breeding herd, then disease
             introduction issues will not be the same as for a closed breeding herd or stud.
             An initial quarantine area is appropriate for disease control for introduced stock.
             The length and type of quarantine necessary varies with different diseases and
             should be discussed with your veterinarian, (quarantine may be necessary from
             a weed perspective too). Attention to secure boundary and internal fencing is
             an integral part of the strategy.



            Further information
            Contact state departments of agriculture, your private veterinarian or visit the
            Animal Health Australia website at www.aahc.com.au




            30            MLA More Beef from Pastures – Toolkit 7
                                                                                         Toolkit 7
Tool 7.14 Diagnostic tools to assess
disease status
Diagnostic tools to assess the Bovine Johne’s Disease (BJD) and Mucosal disease
(Bovine Pestivirus) status of introduced cattle.



  Disease                  Diagnostic tool


  Bovine Johne’s           Blood: Serology absorbed ELISA takes about 3 days
  Disease                  and has a sensitivity of about 25–50% and about 1%
  (BJD)                    false positives – suited to herd screening rather than
                           individual testing.
                           Faecal culture to detect bacteria is more accurate
                           (sensitivity 30–50% and 0% false negatives).
                           Conventional faecal cultures take 20 weeks and
                           Bactec takes 8 weeks to perform although Bactec is
                           more expensive.
                           Note that no diagnostic tests are available for
                           individual animals or on a mob basis that give a high
                           level of assurance of freedom from BJD.
                           Post mortem examination followed by histopathology
                           and culture of gut tissues may be undertaken on
                           serological positive animals.



                           Clinical signs: wide range of signs depending on
  Mucosal disease
                           strain of virus and time of infection. Can vary from
  (bovine pestivirus)      mild diarrhoea to chronic ill-thrift and wastage in
                           cattle up to 18 months to sudden death of cattle
                           between 6 months and 2 years of age, poor
                           reproductive performance in breeding herd.
                           Serological testing for presence of antibody and
                           testing of serologically negative cattle for presence of
                           virus (antigen).
                           The diagnosis of mucosal disease will require
                           veterinary input to assist in diagnosis with autopsy,
                           serological testing and histopathology.



  The diagnosis of the diseases listed is likely to require advice and assistance
  from your veterinarian.




                             MLA More Beef from Pastures – Toolkit 7                31
Toolkit 7

            Tool 7.15 Strategies to lessen the impact
            if disease is introduced
            Strategies for managing Bovine Johne’s Disease (BJD) and mucosal disease (bovine
            pestivirus).



              Disease                 Management strategy


              Bovine Johne’s          Eradication versus living with BJD
              Disease                   • Cost benefit of eradication (and feasibility) This
              (BJD)                       should only be considered in consultation with
                                          your veterinary consultant and financial advisor.
                                        • If living with the disease, structure stock sales to
                                          minimise ongoing impact of disease, For example
                                          try to target stock for slaughter rather than store
                                          sales. Run a young herd and if mortalities are an
                                          issue consider a test and cull program. Plan a
                                          property management program in conjunction
                                          with your veterinarian.


              Mucosal disease           • Define pestivirus status in herd with serological
              (bovine pestivirus)         testing of mobs.
                                        • Identify and cull persistently infected cattle in
                                          conjunction with your veterinarian if outbreak
                                          has occurred.
                                        • Expose naive breeding cattle before mating to
                                          ensure they are immune when pregnant.
                                        • Vaccination: Pestigard™ Vaccine (see Procedure 2).




            32            MLA More Beef from Pastures – Toolkit 7

				
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