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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 Visit our web site at: http://www.uaex.edu 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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