The disease is caused by the bovine herpesvirus 1

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The disease is caused by the bovine herpesvirus 1 Powered By Docstoc
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      Control:                                                             Death is rare except in newborn calves or in cases
      By quarantine. Vaccination is possible but appropriate           complicated by secondary infection. T he virus can persist
      vaccines may not be easily available.                            for life in cattle after clinical recovery and may be re-
                                                                       isolated from the nose, vagina or prepuce.
      INFEGIOUS BOVINE RHINOTRACHEITIS (IBR) AND
      INFEGIOUS PUSTULAR VULVOVAGINITIS (IPV):                         Diagnosis:
      IBR is found throughout Indonesia including North                Based on the clinical findings . Confi rmation can be sought
      Sumatera, but has not yet been accurately mapped out.            by isolation of the virus from nasal or genital secretions
      The disease is caused by the bovine herpesvirus 1.               during the acute stage of the disease or antibody in the
          IBR or IPV are highly contagious conditions which            serum. In fatal cases, formalised sam ples of trachea and
      affect either the upper respiratory tract or, less commonly,     lung may be useful for histopathology. IBR must be differ-
      the genital tract. Rarely the virus invades the central          entiated from other infections notably MCF and
      nervous system causing encephalitis, and sometimes it            rinderpest.
      affects the foetus causing abortion. The disease is seen in      Treatment and comrol:
      male and female cattle and buffalo . The IBR syndrome            Affected an imals should be isolated as soon as clinical
      spreads by the airborne route when there is a close contact      signs appear. Broad-spectrum antibiotics are useful in
      between sick and healthy animals. The IPV syndrome is            countering secondary infection . Vaccination may be useful
      usually spread venereally and may be overlooked unless           in affected areas but there is a risk of abortion if the
      the cow is examined closely. The male equivalent [infec-         vaccine is administered to pregnant cows.
      tious balanoposthitis C IBP)1 causes lesions on the penis        BOVINE EPHEMERA L FEVER {BEF}:
      and prepuce of the bull.
                                                                       Also known as three day sickness, stiff sickness, bovine
      Symptoms:                                                        epizootic fever, this acute infection is caused by a
      T he onset of IBR is shown by a sudden high fever, loss of       rhabdovirus and is insect transmitted.
      appetite, conjunctivitis, a serous discharge from nose and           BEF is characterised by an acute fever of short
      eyes and increased salivation. Later the discharge become        duration often accompanied by stiffness or lameness.
      purulent. In lactating cows the m ilk yield often falls          Commonly the morbidity rate is high but mortality is low,
      dramatically. In pregnant cows abortion may occur at             usually less than 1'Xl. BEF has been reported and
      about 6 to 8 months of gestation. Occasionally there is          serological surveys have indicated that some Indones ian
      coughing or nervous signs .                                      cattle have serum ne utralising antibody to BEF virus . The
          The IPV syndrome is less serious and includes fever,         disease also occurs in Malaysia and probably other
      tail switching, painful urination, swollen vulva, petechiation   Southeast Asian countries.
      and pustule and erosion formation in an inflamed vagina.
                                                                       Symptoms:
      There may be a thick yellowish discharge or pseudomem-
                                                                       Fever which may last 1 to 4 days, lachrymation, dyspnoea;
      braneous form. Genital IBP lesions in bulls are similar but
                                                                       sick animals refuse food and water because swallowing is
      restricted to the prepuce and penis; the testes are not
      infected .                                                       painful. There is nasal discharge and drooling of saliva .
                                                                                                              S
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                                                                                                                                         5
Rumination ceases for about 2 days with diarrhoea in               polioencephalomyelitis. Most affected calves are unable
some cases, constipation in others. In lactating cows there        to stand, and show incoord ination, ataxia, paralysis of
is a sudden and severe drop in milk production. The yield          one or more limbs, muscle atrophy, exophthalmos and
returns to normal in about 2 weeks, but cows affected late         lachrymation .
in lactation may dry off. Mastitis sometimes develops and          arthrogryposis. The joints of one or more limbs are
cows in advanced pregnancy may abort.                              fixed usually in flexion. There is muscle atrophy;
    In most cases affected animals recover completely.             severely affected calves arc usually dead at term and
Mortality is usually less than 0 .5%, but it may be higher if      associated with dystocia.
the animals are under stress.                                      hydranencephaly. Mostly blind calves, unable to suck;
Diagllosis:                                                        poor response to stimuli, the behaviour varies from
In the field a provisional diagnosis is made usually on            depression to hyperexcitability; deformed skulls.
clinical observations . Laboratory tests require paired serum      microencephaly (abnormally small brain) . T hey are
samples collected 10 to 14 days apart which should be              'dummy' calves, uncoordinated and unable to stand.
submitted to a central laboratory with adequatc diagnostic      Diagnosis:
facilities .                                                    May be made from clinical signs, and the pathology of
TreallilCllt alld controL:                                      congenital defective calves. T he diagnosis is confirmed by
No treatment is satisfactory. Vaccination, except in            demonstration of specific antibody in the serum of the
valu able breeding animals, may not be warranted because        newborn animal collected before it has taken colostrum.
this is a relatively mild diseasc.                              Virus can be isolated from the affected calves.
                                                                TreaTlIlenT alld controL:
AKABANE DISEASE:
                                                                T he usual practice is to destroy affected an imals. Care
Akabane disease is a term used to dcfine congcnital defects
                                                                should be taken not to import pregnant an imals from non-
in calves due to infection with Akabane virus and other
                                                                endemic areas to endem ic areas.
pathogenic viruses in the Si mbu group of bunyaviruses. It
is believed that transmission occurs solely by blood sucking    JEMBRANA DISEASE (JO):
insects.                                                        Jembrana disease is considered to be a problem especially
SYlilptoms:                                                     in Bali cattle . It is concentrated on the island of Bali, but a
Infected young and adult animals show no clin ical signs        syndrome with similar characteristics (Rama Dewa) is also
but when infection occurs during pregnancy the virus            recognised in Lampung in the province in South Sumatcra
passes to the foetus causing scvere disease of its central      and in East Java. To datc, JD has only been diagnosed in
nervous system. The first observed manifestations of an         Indonesia. The causal agent has not yet been clearly
outbreak are late abortion and stillbirths . The more           identified but a filterable agent, probably viral, is involved .
generally recognised forms of the disease are seen in live      Jembrana disease is an acute, infectious cond ition usually
calves with a variety of developmental defects depending        with a low mortality rate. Buffalo, Bos indicus and other
on the time of infection during pregnancy:                      breeds may be less susceptible. T he case mortality rate is
                                                                usually less than 10%.
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      Symp toms:                                                         Treatment and contml:
      T hese include feve r, anorexia, mild lachrymation and hyper-      Tetracyclines give variable results. Spraying the animals
      salivation and enlarged lymph glands (Photograph 5.2.4).           with insecticide has also been re ported as a precau tion to
      Blood sweating, bloody diarrhoea and moderate, temporary           control the disease but is of doubtful value. T he possibility
      anaemia are inconstant. Pregnant animals may abort.                of vaccination is being investigated.
      Diagnosis:                                                         (iii) Parasitic diseases:
      Is based on the history, clinical signs, and the pathology of
                                                                         Internal parasites
      affected organs. A serological (ELISA) test is now
      available for diagnostic or epidemiological studies. From          TR YPANOSOMIASIS (SURRA) :
      fatal cases, tissues for diagnos is should include small           T he common pathogenic trypanosome in many parts of
      blocks of anterior lobe fro m lung, mediastinal lymph node,        Asia is Trypanosoma evansi. The parasite infects horses,
      liver, kidney and brain including choroid plexus, all fixed        cows and buffalo and the disease can be epidemic causing
      in 10% formalin .                                                  heavy mortality. Flies of the genus T abanus ( T. rubidus
                                                                         and T. Ineganops) are among the main transmitters. T he
                                                                         parasite has been detected in all main Indones ian islands
                                                                         except Sumba, Flores, Maluku and Iria n Jaya. It is also
                                                                         present in India, M alaysia, Thailand and Vietnam . T he
                                                                         disease can vary from inapparent infection to acute forms,
                                                                         with death in a fe w days. In endem ic areas cattIe and
                                                                         buffalo norma lly fo rm su bclinical res ervoirs of infection .
                                                                         Overwork has been reported to distu rb th e equilibrium
                                                                         between hos t and trypanos ome in carrier animals and
                                                                         clinical episodes with signi fica nt mortality have occurred .
                                                                         Acute outbreaks are seen in non-immune animals intro-
                                                                         duced into endemic areas, e.g. in imp orted callIe and
                                                                         bu ffalo. The disease can be severe in horses in eastern
                                                                         Indones ia where preventive measures are ro utinely used.
                                                                         SYIllP 10 illS:
                                                                         Anaemia is the m ost consistent clinica l featu re of
                                                                         trypanosomias is. Also noted are prolonged bleeding times
                                                                         in a wounded animal. T emperature elevati on occurs
                                                                         d uring acute parasitaemia. A reduction in fe rtility may be
      Photograph 5. 2.4                                                  fo und .
      lembrana disease. Enlargement of prescopu/ar and sub iliac lymph
      glands. The animal also showed fever and diarrhoea. Bali heifer.
                                                                                                       TH       GHT
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                                                                                                                                                   5
Diagnosis:                                                                 Trealment and control:
Trypanosom es are readil y seen in blood fil m s in acute                 Drug therapy early in an uncomplicated syndrome will
disease, but low paras itaem ias occur in chronic infections .            p rodu ce dramatic recovery but advanced cases with
Blood in an ticoagulant should be fo rwarded to a veteri nary             considerabl e destru ction of red blood cells will only
laboratory for confirm ative diagnosis. Both direct staining              resp on d to blood transfu sion. Among the drugs used are:
and serological tests (e. g. ELISA) are now used .                        Trypan blue, acriflavine, p henamidine, ganaseg, acaprin
Trealii/eill and C011l ro L:                                              and imizole. Preventive m ethods available are: control of
Suram in (naganol) is the m ost com m on d rug used in                    tick vectors, vaccinati on of susceptible anim als, treatment
Ind onesia. P reventive m easures include detection and                   of infected animals, control of stock m ovem ents, good
treatm ent of infected animals, protection of animals fro m               nutrition and a voidance of stress. Im ported livestock
b iting fli es, the control of sale of m eat from infected                should not be introduced to an endemic area without
animals, the control of stock m ovem ent and avoidance of                 previous vaccin ation .
stress . Livestock introduced for th e first time into endemi-            ANAPLASMOSIS:
cally infected areas sh ou ld be given prop hylactic treatment.           Anaplasm osis is an acute, subacute or chronic disease of
It should be noted that they m ay be equally su sceptible to              cattle caused by A naplasma IIw rginaLe and is transmitted by
other local infections, e.g. an aplasmosis. A th orou gh                  the same ticks which transmit babes iosis. T he disease has
knowledge of the regional epidemiology m ay save th e lives               been reported in Su m atera, Java, Bali, K alim antan ,
of many cattle and buffalo.                                               Sulawesi and elsewhere in South and Southeast Asia.
BABESIOSIS:                                                               Calves u p to a year old suffer a mild form wh ich m ay be
Babesiosis caused b y the protozoan parasites Babesia bovis               symptomless and recovery results in a lasting immunity
and Babesia bigelililla are transmitted by til e ticks Boophilus          and a carrier state. At th e age of 2 to 3 years th e disease is
III icropills, A lIlbly olllllla leslillUdillQl"IIlI1 or Rhipicephalils   acute but rarely fatal. In cattle over 3 years old it m ay be
pilallS . T he disease has been reported in Sumatera, Java,               peracute and fatal.
Sulawesi and Kali m antan as well as in other Southeast                   SYIllPIOIIIS:
Asian countries.                                                          In clinical cases fever, loss of appetite, weight loss,
S:VII IPIO IIIS:                                                          dehydration, constipation, d ys pnoea, anaem ia and pale
T he clin ical infection is characterised by high fever, loss of          yellowish mucous m embranes, urination is frequent but
appetite, anaem ia and hacm oglobin uria (red water) . Calf-              normal in colou r. T he animal is weak and walks witll a
hood infecti on produces a m il d disease but susceptibl e                stiff gait. Abortion m ay occur and recovery is slow.
adult cattle show acute symptoms.                                         Diagllosis:
Diagllosis:                                                               Is based on the p resence of Anaplasma sp p. in the stained
Clinical findi ngs and d em onstration of Babesia spp in red              red blood cells and on the clini cal sym ptoms.
cell s in bl ood smears fi xed in m ethanol and stained with
Giemsa is considered diagnostic.
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      Treatment and control:                                           GASTRO -INTESTINAL HElMINTHIASIS:
      Treatment with oxytetracycline is effective. Carrier infec-      In cattle, gastrointestinal roundworms cause clinical and
      tions can be eliminated with long acting oxytetracycline         subclinical disease, producing economic loss between 1
      (20 mg/kg intramuscularly twice, 7 days apart) . Vaccin-         and 4 months of age ( Toxacara viwlorum ) and for the firs t
      ation should be carried out when susceptible cattle are          5 to 10 months after weaning (mixed strongyles). Buffalo
      moved to an area where anaplasmosis is endemic.                  calves, 1 to 4 months old, are also fatally affected by T.
      FASCIOLIASIS (LIVER FLUKE):                                      villllorwil but less severely by strongyles. Calves acquire
                                                                       infection with T. vitlllorum from larvae in the milk for the
      Fascioliasis has been reported in most parts of Indonesia and
                                                                       first 6 to 8 days after birth. Larvae of most species of
      Asia generally. Prevalence rates up to 90% have been
                                                                       strongyles are eaten with grass but some species are also
      recorded. The most common fluke is Fasciola g(gantica.
                                                                       able to penetrate the skin and become important when
      Acute cases are rare in draught animals and the parasite is
                                                                       calves are reared in crowded, wet unhygienic pens . Calves
      usually undetected until meat inspection in abattoirs. T he
                                                                       on a low plane of nutrition are more severely affected by
      flukes require aquatic snails for their development and multi-
                                                                       roundworms than well fed calves.
      plication. Animals become infected by eating rice stubble and
      grass growing in or around permanent water, or drinking          Symptoms:
      water containing the infective stages (metacercariae).           Anorexia, weight loss or poor weight gain, diarrhoea,
      Symptollls:                                                      anaemia and ascites .
      In severe chronic cases there is anaemia, emaciation and         Diagnosis:
      weakness, reduced milk yield and reproductive perfor-            Gastrointestinal helminth iasis should be suspected in
      mance, anorexia, oedema of the jaw, ascites and jaundice.        an imals 1 to 4 months of age and in calves for the first 10
      Diagnosis:                                                       months after weaning; especially those reared intensively in
                                                                       groups in wet unhygienic pens and on a low plane of
      The presence of liver fluke eggs in the faeces detected with
                                                                       nutrition. Faecal egg counts are a useful aid to diagnosis
      a microscope is proof of the disease but does not neces-
                                                                       but can be misleading. T he clinical picture is therefore
      sarily indicate the degree of severity.
                                                                       important.
      Treatlllent and control:
                                                                       TreatH/em and control:
      Treatment and control methods are available such as
                                                                       Control of T. viwlonl1t/ is achieved by treati ng calves orall y
      control of snails, sanitation and chemotherapy; however
                                                                       with 300 mg of pyrantel once between 10 and 16 days of
      they are rarely used because of cost and inadequate
                                                                       age. A single treatment wi th levamisole at 10 mg/kg is also
      knowledge of the epidemiology. In areas of known severe
                                                                       effective but calves must be weighed to ensure the correct
      infection a degree of prevention may be obtained with a
                                                                       dose is administered. W ith these treatments the parasites
      wide range of compounds but the choice may depend on
                                                                       will be elim inated from the intestine while still larvae and
      the local ep id emiology. Essentially animals should not be
                                                                       thus recontamination of the environment with eggs will be
      given access to herbage from aquatic habitats which
                                                                       prevented .
      contain the snail intermed iate host.
                                                                                             TH        H
                                                                            MANAGEMENTAND HEAL OF DRAUG TANIMALS                      153




                                                                                                                                            5
    Control of strongyles is probably not necessary in             fenitrothion once daily for 30 days. Control measures
buffalo calves, or in calves from cattle that are reared after     include control of fly vector with insecticidal ear tags, good
weaning with adult animals under extensive conditions, or          nutrition and treatm ent of infected animals with topically
in calves reared in hygienic pens and fed cut-and-carry            applied organophosphates (e.g. trichlorfon) may be tried.
fodd er, or a high quality ration (especially high protein).       EXTERNAL PARASITES
However, where calves from cattle are reared after weaning
                                                                   A number of arthropods, \\'hich inclu de flies, mosquitoes,
on a low plane of nutrition, in crowded unhygienic pens or
                                                                   lice, fle as, mites and ticks, may impair productivity. They
intensively on pasture as a group with other weaners,
                                                                   cause loss of condition and damage to hides through
strongyle parasites may be expected to suppress growth
                                                                   intense irritation of the skin and mechanical activity . Some
rate and animals may die. U nder such conditions control
                                                                   are also im portant vectors of viral, bacterial , fungal,
can be achieved by changing management or by treating
                                                                   protozoan and other diseases. In general a warm humid
animals with anthelmintic each 2 months for 2 or 3 treat-
                                                                   climate and low nutritional status of animals favours multi-
ments, commencing 2 months after weaning. All modern
                                                                   plication of these parasites .
broad-spectrum anthelm intics are effective and choice
                                                                       Lice which breed on the animals are the easiest to
should be made on the basis of availability and price.
                                                                   control, and are susceptible to almost all insecticides . Two
CASCADO (STEPHANOFILARIASIS)                                       treatments are req uired , first to kill lice which are present
The disease is caused by Stephal/ojilaria dedoesi and tl1e         on the animal at the time and the se cond 10-1 4 days later
prevalence is high in some areas, e.g. Sulawesi. The worm          to kill lice which have hatched fro m the eggs anached on
produ ces a dermatitis. T he disease is spread by biting fli es.   the animal hair.
Symptollls:                                                            Ticks are the biggest problem in many parts of the
Lesions occur on the sides of tl1e neck, the withers, dewlap,      world but are less important in draught animals which are
shoulders and around the eyes . A small number of small            usually more resistant breeds and because they are
papules develop and coalesce LO form a larger lesion covered       regul arly cleaned by their owners. Bos tau m s breeds are
by crust, the hair falls out and the skin thickens with blood      signifi ca ntly more susceptible to infection than Bos illdiClls
and lymph which can be squeezed out readily. The lesion            or Bos taums crosses.
extends outwards while the centre becomes hard and covered             C hemicals for control of arthropods may be sprayed by
with a thick, dry crust and may reach a size of 25 Col in          using hand or motor operated pumps . The simplest way
diameter. Itching leads to rubbing and aggravates the lesion.      for smallholders is wash ing with a cloth, brush or sponge
                                                                   dipped in a bucket. Insecticide or acaricide mixture applied
Diagnosis:
                                                                   in selected areas of the body will suffice. Backline pour-on
Demonstration of adult worms or micro fi lariae in skin            appli cation of parasiticide is more practical but less satis-
scrapings.                                                         factory than dipping. It must be emphasised that most of
Treatlllent and conlrol:                                           the chemicals used are very poisonous, especially in their
Ointments containing 40'% trichlorphon, 4% Supona-20               concentrated form. T herefore they should be handled
twice daily for 15 days or once daily for 30 days , or 4%          carefull y and diluted before use exactly as directed by the
                                                                   manu factu rers .
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        In villages at night, fa rmers repel flies, midges and             Make sure the calf is dry and warm. It should be
      mosquitoes from the host by burning grass or wood .                  closely inspected at least twice daily for signs of injury,
      5.2.2 Calves                                                         illness or distress.
                                                                           The navel cord should be squeezed and tied about 2.5
      (i) Management and care of calves                                    cm away from the body and cut below the ligature.
      All healthy working cows should be able to produce a calf            Painting the cord with tincture of iodine or dipping in
      each year. Under traditional systems with simple manage-             20% lysol will avoid any infection.
      ment, various authorities report serious losses in calves in         It is vital that a calf receives colostrum from the
      the first few weeks of life . Such losses can be of great            mother as soon as possible after it is born and
      economic importance to the individual farmer and the                 certainly within the first 6 hours of life; it should
      national economy irrespective of the size of the production          continue to do so for the first 3 days . If the calf is
      unit and should be considered unacceptable. Calves can be            weak and unable to rise it should be assisted in getting
      saved by better care. The following steps are necessary for          a feed of colostrum.
      successful management:                                               De-worm the calf against ascariasis with 300 mg
                                                                           pyrantel at the age of 10 to 16 days .
         Make an effort to identify oestrus in the cow and
                                                                           In known infected areas vaccination againt brucellosis,
         arrange mating or artificial insemination quickly.
                                                                           haemorrhage septicaemia or other diseases shou ld be
         Record the time when the cow is mated to know when
                                                                           arranged at the appropriate age.
         the calf is expected to be born and watch closely for
         signs of impending parturition .                               (ii) Calf diseases
         T he cow should be provided with a clean, dry, well-
                                                                        Mortality in young calves may be a serious problem under
         bedded, well-drained and easily observed stall for
                                                                        vi llage conditions as well as in organised farm ing. Any
         calving .
                                                                        negligence in feeding and management may result in losses
         W he n the cow is showing signs of calving, she should
                                                                        especially during the first three mo nths of age . Problems
         be observed carefully, but not disturbed unless help is
                                                                        with calves may occur at various times:
         needed.
         As soon as the calf is born, the foetal membrane and              abortion of cows,
         mucus should be removed from the nose and mouth of                birth of weak or dead calves,
         the calf and the tongue pulled forward. If the cow calves         disease a few days after birth
         normally, she will immediately begin to lick the newborn          disease in the first three months of life.
         and thus stimulate respiration and circulation and dry the
         calf. If the calf does not breathe immediately, it should be   5.2.3 Abortion
         stimulated by alternately compressing and relaxing the         The causes here already have been discussed in Section
         chest wall (artificial respiration) or by lifting up by its    5.2.1. Factors that are important in determining the cause
         hind legs with a sudden jerk and letting it hang in this       of abortion include the stage of gestation, season of the
         posture for a few m inutes till the start of respiration.      year, geographical location, whether the animals have been