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Culling the Beef Cow Herd FSA

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Culling the Beef Cow Herd FSA Powered By Docstoc
					                DIVISION OF AGRICULTURE
                RESEARCH & EXTENSION                                Agriculture and Natural Resources
                  University of Arkansas System

                                                                                                                                FSA3092





         Culling the Beef Cow Herd

Jeremy Powell                           Introduction                                                     Identifying individual animals in
Associate Professor ­                                                                                the herd is an important first step in
Animal Science                                                                                       developing a record keeping system.
                                            Deciding which cows to cull and
                                                                                                     Ear tags should be permanently
Veterinarian                            which cows to keep in the breeding
                                                                                                     marked and easy to read. Since cattle
                                        herd impacts future herd performance
                                                                                                     lose ear tags, it is useful to have a
                                        and profitability. There are many
                                                                                                     more permanent method of
                                        factors to consider when choosing
                                                                                                     identification, such as ear tattoos.
                                        which cows to put on the cull list.
                                                                                                     Calves should be tagged and tattooed
                                        Production and market conditions can
                                                                                                     at birth and matched with their dams.
                                        influence the priority that is placed on                     Calf birth date and sex should also
                                        different culling criteria. It is often                      be recorded.
                                        easy to recognize “red flags” that
                                        make cows obvious culls (e.g., cows                              Recommended production records
                                        with poor rebreeding performance or                          to keep include cow ID, calf ID, sire
                                        severe cancer eye), but there are other                      ID, calf birth date, calf birth weight,
                                        reasons to cull cows. The challenge in                       calf sex, calving ease score, breed of
                                        selecting cull cows is identifying the                       dam, breed of sire, breed of calf,
                                        cows that are making the operation                           weaning date and weaning weight.
                                        money and the cows that are losing                           Collection of weaning weights requires
                                        the operation money.                                         a scale, so plan ahead if a scale needs
                                                                                                     to be acquired or borrowed. Because
                                        Recording Information for                                    adjusted calf weaning and yearling
                                        Use in Culling Decisions                                     weights take the age of dam into
                                                                                                     consideration, ages of breeding
                                                                                                     females should be recorded. If cow
                                            Recognition and assessment of
                                                                                                     ages are unknown, they can be
                                        poor animal performance or other
                                                                                                     estimated by observing the number of
                                        factors that might call for animal
                                                                                                     incisors as well as the degree of
                                        culling require organized data
                                                                                                     tooth wear.
                                        collection and record keeping. The
                                        keys to an effective record keeping                               Breeding records should include
                                        system are: 1) decide what production                        lists of all cows and heifers exposed to
                                        and financial information is useful                          either natural service or artificial
                                        and practical to collect, 2) collect                         insemination. This information is
                                        accurate information in a timely                             important for calculating calving and
                                        manner, 3) manage that information                           weaning percentages and assessing
                                        in a usable form and 4) use the                              reproductive performance.
Arkansas Is
                            information. Record keeping can be as                        Insemination dates, bull ID and
                                        simple as handwritten notes in a
Our Campus
                             pocket­sized record book or as
                                                                                                     female ID should be recorded for
                                                                                                     artificial insemination. For natural
                                        advanced as data entry into a                                service, recorded information should
                                        computerized record keeping system.                          include bull IDs, female IDs and
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                          University of Arkansas, United States Department of Agriculture, and County Governments Cooperating
breeding season dates. Identify and record the IDs of    potential. Even bulls that have passed a recent
non­pregnant cattle for future reference in culling      breeding soundness evaluation can be ineffective
decisions. In addition, health records and herd          breeders if they do not display the libido to seek out
management practices should be properly recorded as      and breed cows in heat or become injured during the
part of herd production information.                     breeding season. The sooner these problems are
                                                         recognized, the sooner the breeding program can get
    The University of Arkansas Cow Herd                  back on track.
Performance Testing Program is designed to collect
performance information that can be used in cull cow     Poor Performance
decisions as well as replacement heifer and sire
selection decisions. Calf growth performance, calf           Poor calf performance is usually the result of
muscling, cow and calf frame size, cow efficiency        inferior genetics, poor dam milk production, calf
(adjusted 205­day calf weight ÷ cow weight), most        sickness or a combination of these factors. Cows
probable producing ability (a measure of the lifetime    transmitting inferior genetics to their calves for
productivity of the dam in terms of calf adjusted 205­   economically important performance traits and cows
day weaning weight ratios), cow body condition and       with unacceptably low milk production are potential
calving interval are evaluated as part of the program.   culls. If poor calf performance is due in large part to
                                                         calf sickness and not associated with the dam, then
Culling Criteria                                         the dam may still have a productive future in the
                                                         herd. The age of the dam should also be considered
                                                         when culling for low performance as first­ and
Pregnancy Status
                                                         second­calf heifers should not be expected to perform
                                                         at the same level as older cows.
    One of the greatest determinants of profitability
in a cow­calf operation is reproductive rate. Open
                                                             Cows exhibiting poor performance over several
(non­pregnant) cows are a drain on resources. They       calving seasons are not likely to show greatly
consume feed, forage and other resources without         improved performance in future calving seasons.
producing a marketable calf to contribute to expense     Information from the University of Arkansas Cow
payments. A productive cow is expected to produce a      Herd Performance Testing Program revealed that
calf at least once a year. Cows that are open at the     most cows ranking in the bottom one­third of the
end of the breeding season should be at the top of the   herd for calf 205­day adjusted weaning weights
cull list. Cows that calve outside of a controlled       consistently ranked in the bottom one­third of the
calving season are also potential culls, particularly    herd over a period of several years, regardless of cow
when feed and forage supplies are running short.         age. Therefore, identification and culling of poorly
Late­calving cows should be scrutinized as well,         performing herd females can be effective for
because they have less opportunity to breed back to      improving herd performance averages.
stay within a controlled breeding season.
                                                             While herd genetic improvement is largely
    Closely observe the herd for cows returning to       dependent on sire selection, the dam contributes half
standing heat after breeding or artificial               of the genetics to the calf. Expected progeny
insemination. Identify open cows by rectal palpation     differences (EPDs) provide valuable information
(60 to 90 days post breeding season). Palpating cows     about expected genetic merit and are available on
earlier than this can induce abortions in short­term     many seedstock cows. Culling cows with EPD values
pregnancies. Waiting too long to palpate simply          that do not compare favorably with breed or herd
allows an unproductive animal to consume more            averages for economically important traits
resources. Pregnancy status can also be determined       contributes to herd genetic improvement. Many breed
with ultrasound technology. Ultrasound offers more       associations publish breed averages and percentile
accurate fetal age determination and the option of       ranking tables for EPDs for active dams. When using
fetal sexing under certain conditions, but it is often   EPDs, a balanced selection approach instead of a
more difficult to schedule and more expensive than       focus on single trait selection will help limit
rectal palpation.                                        unacceptable performance tradeoffs.

    Pregnancy checking can help identify herd health         Another consideration when evaluating cow
and fertility problems. If an unusually high             genetics is the marketability of traits passed on to
percentage of the cow herd turns up open, then           calves. Feeder calf premiums and discounts are based
reproductive diseases, inadequate herd nutrition or      on market specifications for frame size, muscling,
bull infertility are potential culprits. A breeding      conformation and structure, breed composition, coat
soundness examination is an excellent tool for           color, etc. Calf uniformity also impacts prices paid for
identifying bulls with unsatisfactory breeding           calves sold in groups. Culling cows that are extreme
in terms of frame size (very small or very large), for   adequate available nutrients. “Smooth­mouthed”
example, is not only useful for producing calves         cows have teeth worn down to the gums (Figure 1).
within a desirable frame size range, but culling can     Cows may also lose teeth at any age from being
also improve calf crop uniformity. Calf marketing        knocked out by blunt force or from gum disease or
plans will influence the selection of cull cows based    infection, resulting in a “broken­mouthed” condition.
on the importance of different traits for different      These cattle may dribble feed from the mouth and
marketing options. For calves marketed for stocker or    have a hard time consuming adequate quantities of
backgrounding programs, desirable levels of post­        feed or forage. Lumpy jaw is another condition of the
weaning growth performance are needed. When              mouth that can negatively impact grazing ability
calves are marketed for finishing programs that pay      (Figure 2). Annual inspection of the teeth and mouth
premiums for carcass merit, selection and culling of     during routine cattle working is recommended.
breeding animals for carcass traits is important.
                                                         Udder
Age
                                                              Udder soundness affects
    The productive lifetime of a beef cow is variable.   milk production, milk
As long as teeth, udders, feet and legs are sound,       consumption and ultimately
many older cows are still able to perform well. Breed    calf weaning weights. Proper
and production environment can play a role in            udder attachment in a beef
longevity. Florida research on Brahman­influenced        female is important for a long,
cows indicated that there was a consistent               efficient, productive life. A
rebreeding performance through about 8 years of age      sound udder should be firmly
and a decline in reproductive performance after 10       attached with a strong, level
years of age. An even steeper drop in reproductive       floor and four properly formed
performance occurred in cows beyond 12 years of age.     teats proportional to body size.
In addition, with an emphasis on herd genetic            Weak udder suspension results
improvement, younger beef females are often              in pendulous udders that are
genetically superior to older cows. Ideally, cows        difficult for a sucking calf to
should be culled for advancing age prior to a sharp      nurse. Balloon or funnel­
                                                                                            Figure 3. Balloon
                                                                                            teats.
decline in reproductive or maternal performance.         shaped teats are also difficult
                                                         to nurse and may hurt calf
Mouth                                                    milk consumption and weaning
                                                         weight (Figure 3). Balloon teats are sometimes an
    Teeth wear with normal use over time. Gritty         indication of past mastitis (a bacterial infection of
feeds and forages accelerate tooth wear, so soil type    the mammary tissue). The udder should be healthy
(sandy soil) can affect how long teeth remain sound.     and free of mastitis in all four quarters for good
Cows can eventually wear their teeth down to a           milk production.
stage where grazing effectiveness is severely
impacted. This results in poor body condition despite    Structural Soundness

                               Figure 1. “Smooth­
                               mouthed” cows.
                                                              Structural soundness is important from the
                                                         standpoint of functionality. Structural problems
                               Figure 2. Lumpy jaw.      subject the
                                                         joints to
                                                         excessive
                                                         wear and
                                                         stress that
                                                         can
                                                         eventually
                                                         hamper
                                                         mobility. For
                                                         example, a
                                                         cow with poor Figure 4. Cow with poor hip structure.
                                                         hip structure,
                                                         exhibiting too much slope from her hooks to her pins,
                                                         may become lame (Figure 4). Cows that have
                                                         difficulty moving around the pasture may be less
                                                         active grazers. Cows need to be sound enough for
                                                         effective grazing and successful pasture breeding.
Condition and performance of structurally unsound         animal. Culling
or crippled cattle often go downhill. Obvious             is often the best
structural defects can decrease the market appeal of      option once an
an animal as well.                                        affected cow has
                                                          weaned her calf.
    Lameness is a major reason for culling cattle.        Treatment
Lameness leads to decreased performance, decreased        options depend
reproductive efficiency, weight loss and increased        on the size and
treatment costs. A study of five large western feedlots   development of
showed that lameness accounted for approximately          the tumor when

                                                          found (Figure 5). Figure 5. Different stages of
$121 loss per lame animal. Many conditions can be         it is initially
                                                                               cancer eye.
the cause of lameness in cattle including foot rot,
laminitis, joint injury and fescue toxicosis.             Procedures
                                                          involving very high or low temperatures or surgical
    Foot rot (interdigital phlegmon) is an acute          removal of part of the eye can be performed
bacterial infection of the skin between the toes and      depending on the size and location of the tumor.
deeper structures. Fusobacterium necrophorum is the       Whole eye removal is another option if the eye is not
organism most commonly associated with this               salvageable. Often treatment will only shrink the
disease. These bacteria invade the foot after trauma      tumor, and regrowth may occur at some point.
occurs or with skin softening from wet or muddy           Genetic selection for dark pigmentation around the
environments. Clinical signs include swelling, redness    eyes is also effective in reducing the incidence of
and pain associated with the affected foot. Treatment     cancer eye in the herd. Animals with the dark
should include a systemic antibiotic such as              pigment have a significantly reduced predisposition
oxytetracyline. Attempts should be made to clean the      for cancer eye.
affected area and remove unwanted dirt and debris.
Topical applications of copper sulfate or iodine will         Another health issue that may determine if a cow
also aid in healing. Prevention of foot rot is best       should be culled from the herd is Johne’s disease.
accomplished by improving management practices to         Paratuberculosis, or Johne’s disease, is a chronic,
reduce foot trauma as well as wet or muddy pasture        incurable, contagious infection of the intestinal tract.
conditions. Vaccines are available to help prevent the    This disease is caused by the bacterium,
disease if a herd is experiencing severe problems.        Mycobacterium paratuberculosis, which can survive
                                                          in the environment (soil, pasture, etc.) for periods
    Laminitis (also known as founder) is a disease        longer than one year. Infection occurs in young
that can lead to severe lameness. This disease is         animals, but clinical signs of the disease do not
typically due to overeating grain or rich forage, which   usually develop until animals are older than 18
leads to rumen acidosis and release of endotoxins         months. Calves usually become infected when they
that can damage proper blood flow to the foot.            nurse udders that are contaminated with infected
Laminitis may also be secondary to stress, ration         fecal material or when they are housed in
change, uterine infection or hormone changes. Cattle      contaminated pens or pastures. Johne’s disease
less than three years of age are usually affected.        causes severe, explosive diarrhea and weight loss in
Clinical signs of this disease include stiff gait,        adult cattle leading to enormous production losses in
continuous weight shifting to relieve pressure from       infected herds. Since there is not an effective
affected feet, bounding pulse, as wgs, dropped sole,      treatment or cure for Johne’s disease, the best way to
deformed foot and white line separation. Chronic          keep infected cows from spreading it to others in the
changes can lead to permanent lameness, which may         herd is to cull them. Serological blood tests or fecal
result in the need to cull the animal.                    culture tests may be performed to identify
                                                          infected cattle.
Health
                                                          Prolapse
    Cancer eye is the most common and the most
economically significant tumor of cattle.                     Prolapse can occur before or after calving and can
Approximately 70 percent of all eye tumors in cattle      be vaginal or uterine in nature. A vaginal prolapse
are cancerous. Cancer eye is an aggressive disease        occurs when vaginal tissue protrudes through the
that can infiltrate tissue surrounding the affected eye   vulva where it is exposed to the outside environment,
and invade lymph nodes near the lesion. Tumors that       potential injury and disease­causing agents
result in extensive invasion can impair a cow’s ability   (Figure 6). Vaginal prolapse typically occurs during
to raise her next calf. Once a cow is noted to have the   late gestation as calving approaches. Although
disease, a decision should be made to cull or treat the   vaginal prolapses can be corrected, they are likely to
                            recur. Because vaginal          need to be immediate. In situations where cows are
                            prolapses are known to          being culled for low performance or other less urgent
                            have a genetic component,       factors, it often makes sense to wait until after
                            cows suffering from this        nursing calves are weaned. If marketing conditions
                            condition should be marked      are such that even cows weaning low­performing
                            for the cull list. Daughters    calves are generating a profit, it may be cost­effective
                            of cows with this problem       to hold onto these cows in the near term and then
                            have an increased risk of       market them before they become unprofitable.
                            experiencing vaginal            Production conditions can also influence the best time
                            prolapses, and bull or          to remove cows from the herd. During drought or
                            heifer calves retained out of   other conditions where forage and feed resources are
                            a cow with a history of         limited, culling deeper into the herd is
                            vaginal prolapse can            often appropriate.
                            multiply the problem
Figure 6. Vaginal prolapse. within a herd.                      Maintaining or increasing herd size requires
                                                            adding females to the herd to replace cull cows. When
     Uterine prolapses usually occur at or shortly
                                                            the cost of replacement heifers is high, it may not be
after calving and can be life­threatening. Uterine
                                                            as financially sound to replace cull cows with
prolapse is often associated with difficult calving and
                                                            purchased heifers as when heifer prices are more
is a condition in which the uterus is pulled through
                                                            reasonable. The decision to replace cows with heifers
the birth canal with the calf or afterbirth. If properly
repaired, cows experiencing uterine prolapse may            should take the quality and value of each animal into
never have a repeat prolapse problem. A primary             consideration. Producers with effective genetic
concern with uterine prolapse is making sure that           improvement programs using superior sire selection
affected cows rebreed in a timely manner after the          may find considerable performance differences
prolapse is corrected.                                      between bred heifers and below­average performing
                                                            cows. If the values of potential production
Disposition                                                 improvements and cow salvage returns can cover the
                                                            costs of heifer development, it may be sensible to
    Cattle with unacceptable dispositions are               replace low­performing cows with genetically
dangerous, and culling them reduces the risk of             superior heifers.
injury to both cattle and people. Very excitable cattle
not only are more difficult to handle, but Colorado              Cull cow receipts generally account for 15 to 20
State University research has indicated that calves         percent of gross income in beef cow­calf operations.
with disagreeable dispositions do not gain as well as       Cull cow price levels and seasonal trends should be
calmer calves. Colorado State University studies have       taken into consideration when deciding when to sell
also shown that excitable cattle are more likely to         cull cows. When cull cow prices are trending upward,
produce dark cutter carcasses, which are subject to         it is often advantageous to wait to market cows if the
severe discounts. Because calves inherit a genetic          increasing values can cover added production
component of temperament and pick up habits from            expenses from holding over cull cows. It may also be
their dams during the suckling phase, bad attitudes         advantageous to retain cull cows until weight and
can be propagated within the herd without selection         body condition can be added. Unlike feeder cattle
pressure for acceptable disposition.                        prices, cull cow prices generally increase on a per
                                                            pound basis with increasing cattle weights. If cull
Appropriate Times to Cull                                   cow prices are trending downward, however, it may
                                                            be advisable to market cull cows in a timely manner
    Appropriate times to cull cows from the herd            before more money is invested in cow maintenance,
depend in part on the reasons behind the culling. In        particularly if this investment will not likely be
cases where cows have developed severe health               recovered. In Arkansas, the traditional seasonal highs
problems such as cancer eye, Johne’s disease or             for cull cow prices fall in March, while the seasonal
downer cow syndrome, removal from the herd may              lows usually fall in November.
Selection Checklist                                                       ❑	 Does she have four evenly­spaced, acceptably­
✓ Reproduction                                                               sized teats?
    ❑	 Is she pregnant or open?                                           ❑	 Does she still have teeth that will be effective
    ❑	 Does she breed back in an acceptable time                             for grazing?
       frame and produce a calf every year?
                                                                     ✓ Marketability of Traits Passed on to Calves
    ❑	 Is she too extreme in her muscling pattern?
                                                                          ❑	 Does she have the potential to produce calves
    ❑	 Is her frame size or pelvic area too small,
                                                                             that fit market specifications for frame size,
       making calving difficulty a real concern?
                                                                             muscling, conformation and structure, breed
    ❑	 Is she healthy and in good condition

                                                                             composition, coat color, etc.?
       for breeding?
                                                     ❑	 Does she have the potential to transmit
    ❑	 Is there a history of vaginal prolapse?                               desirable post­weaning growth to calves
                                                                             marketed for stocker or backgrounding
✓ Functionality in a Given Environment                                       programs?
    ❑	 Is her frame size too large for feed and                           ❑	 Does she have the potential to transmit
       forage conditions?                                                    desirable carcass traits to calves marketed for
    ❑	 Is her milking potential excessive for feed and                       finishing programs that pay premiums for
       forage conditions?                                                    carcass merit?
    ❑	 Is she an easy keeper (keeps flesh and

       condition with proper nutrition)?
                            ✓ Performance Potential
    ❑	 Does she have adequate body capacity for                           ❑	 Do performance test results indicate desirable
       carrying a calf and consuming large                                   performance over her lifetime (acceptable
       quantities of forage/feed?                                            Most Probable Producing Ability values and
                                                                             calving intervals)?
    ❑	 Is her breed composition suited to

                                                                          ❑	 If her calf did not perform well, was it due to
       the environment?

                                                                             the genetics or milking ability of the dam?
    ❑	 Is her disposition manageable with available
                                                                             (Calf health problems and sire genetics can
       labor and facilities?                                                 contribute to this.)
                                                                          ❑	 Does she have acceptable Expected Progeny
✓ Maternal Traits                                                            Differences (EPDs) for economically relevant
    ❑	 Does she exhibit desirable maternal instincts                         traits (seedstock operations)?
       (licks off calf at birth, readily accepts nursing
       calf, etc.)?                                                  Summary
    ❑	 Does she milk adequately for acceptable
       calf growth?                                                       Cow culling strategies impact both calf quantity
                                                                     and quality and, when designed and implemented
✓ Structural Soundness                                               effectively, can greatly enhance the profitability of a
    ❑	 Are her feet and legs structurally sound for                  cow­calf operation. Making informed culling decisions
       ease of movement under pasture and                            helps maintain a high level of herd performance.
       breeding conditions?                                          Herd genetic improvement involves not only proper
    ❑	 Does she have desirable slope to her
                         bull and replacement heifer selection, but also proper
                                                                     selection and timely removal of cull cows from the
       shoulders (not too straight)?

                                                                     herd. Even favorite cows should be subject to a
    ❑	 Are her hips level from hooks to pins?
                                                                     systematic culling process to improve cow herd
    ❑	 Are her eyes healthy?                                         profitability. Contact your local county Extension
    ❑	 Is her udder healthy with a level floor and                   office for more information on cow culling or
       good suspension?                                              related topics.




                           Printed by University of Arkansas Cooperative Extension Service Printing Services.
JEREMY POWELL is associate professor ­ animal science                Issued in furtherance of Cooperative Extension work, Acts of May 8 and

veterinarian, University of Arkansas Division of Agriculture,        June 30, 1914, in cooperation with the U.S. Department of Agriculture,

Department of Animal Science, Fayetteville.                          Director, Cooperative Extension Service, University of Arkansas. The

                                                                     Arkansas Cooperative Extension Service offers its programs to all eligible

                                                                     persons regardless of race, color, national origin, religion, gender, age,

                                                                     disability, marital or veteran status, or any other legally protected status,

                                               FSA3092­PD­12­11RV    and is an Affirmative Action/Equal Opportunity Employer.

				
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