Effects of Body Condition on Productivity in Beef Cattle

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Effects of Body Condition on Productivity in Beef Cattle
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Kunkle, William E.
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1.This document is SP-144, one of a series of the Department of Animal Science, Florida Cooperative Extension Service, Institut e of Food and Agricultural Sciences, University of Florida. Publ ication Date: March 1994. Reviewed: December 1997. Formatted for Web: March 1998. Please visit the FAIRS Web site at http://hammock.ifas.ufl.edu The Institute of Food and A g ricultural Sciences is an equal opportunity/affirmative action employer authorized to provide research, educational information and other services only to individuals and institutions that function without re g ard to race, color, sex, a g e, handicap, or national ori g in. For information on obtainin g other extension publications, contact your county Cooperative Extension Service office. Florida Cooperative Extension Service / Institute of F ood and A g ricultural Sciences / University of Florida / Christine Taylor Waddill, Dean 2.William E. Kunkle, Professor, Animal Science; Robert S. Sand, Associate Professor, Animal S cience, and D. Owen Rae, Associate Professor, Large Animal Clinical Science, College of Veterinary Medicine, Institute of Food and Agricultural Sciences, University of Florida, Gainesvil le, 32611.SP-144Effects of Body Condition on Productivity in Beef Cattle1William E. Kunkle, Robert S. Sand, and D. Owen Rae2Introduction Importance of Body ConditionThe income and profit of a beef cattle operation isVariation in body condition of beef cows has closely related to the rebreeding and reproduction rateseveral implications that can be used for management of the herd. A 1986 survey of cattle producers in ninedecisions. The number of days to estrus and milk counties in central Florida indicated the number ofproduction are related to the condition of cows at calves sold was only 69 percent of the breeding agecalving. The services per conception and calving beef cows. Of the 284 producers that responded, 48interval of the cows are related to condition at percent indicated that nutrition was the biggestbreeding. The percentage of open cows, the calving problem they faced in dealing with cattle reproduction;interval of cows that breed, milk produced by the cow, another 24 percent indicated that parasites were theirand the subsequent weaning weight of the calf are biggest problem.closely related to the condition of the cows at calving Nutrition and parasites were factors identified by over 70 percent of producers surveyed; both will affectBody condition affects the amount and type of the body condition of the beef cow. Reproductivesupplements needed during the winter. Fat cows can performance of the beef cow is related to bodylose body reserves, and 1 to 2 pounds per head per day condition, and body condition can be used by cattleof a 30 to 40 percent protein supplement plus minerals producers to make management decisions. Decisionsand vitamins is sufficient to maintain adequate body about grouping cattle and the type and level ofcondition in many situations. In contrast, thin cows supplemental feed for maximum profit should takehave little body reserves and often need 4 to 6 pounds into consideration body condition.or more per head per day of a high-energy supplement This publication will review the relationship ofvitamins to avoid significant flesh losses and body condition to productivity, provide pictures ofreductions in pregnancy rates. beef cattle representative of different body condition scores (BCS), and give a few examples of how bodyBody condition or change in body condition is a condition can help in making management decisionsmore reliable indicator in evaluating nutritional status about your herd.than liveweight or change in liveweight. Although and during the breeding season. with 12 to 16 percent protein plus minerals and

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Effects of Bod y Condition on Productivit y in Beef Cattle Pa g e 2March 1998 Figure 1 Bod y condition score can be evaluated visuall y b y determinin g fat cover in the areas shown ( Oklahoma State Universit y) .cows with higher BCS tend to have higher weights, the body weight alone is not a good estimate of body condition. Most herds have a range in frame and muscling in their cows that make BCS a better measure of body fat than liveweight. Liveweight is also affected greatly by gut fill and pregnancy, which are seasonal, depending on the breeding season, forage quality, and forage availability. In winter feeding studies, the body condition loss is usually much higher than the body weight loss. On many ranches, body condition can be evaluated regularly in circumstances where weighing may be impractical. This technique is easy to learn and can be very useful for making management decisions.Body Condition ScoresBody condition of beef cows is scored from 1 (thin) to 9 (fat); (see Table 1). This system has been used by many cattlemen and researchers as a guideline in evaluating body condition. Any visual scoring system will vary depending on the people doing the scoring, and scoring by different people will not agree exactly. However, among experienced evaluators, condition scores are not likely to vary by more than one score. It is not difficult to evaluate body condition of cattle. First, decide which areas of the body are most useful in determining body condition (Figure 1). Fat deposits are visible over the back, tail head, pins, hooks, ribs, and brisket of cattle. A description of body condition scores is given (Table 1) and pictures of cows representative of BCS 1 to 9 are shown. [BCS: 1, 2, 3, 4, 5, 6, 7, 8, 9] A BCS of 5 should look averageneither thin nor fat. Once you have established what a BCS 5 looks like, it is much easier to determine variations from this. The fill or shrink from digestive contents or pregnancy can change the appearance of moderately fleshed cattle, especially over the ribs or in front of the hooks. Long hair on cattle is another factor that can make it more difficult to visually evaluate the condition of a cow. When hair is long, handling the cattle over the back and ribs, and feeling the flesh over the horizontal process of the backbone in front of the hooks can be helpful. The amount of flesh over the transverse processes, or the sharpness of feel of these bones, can be used to help evaluate body condition. Cattle with condition scores of 3 or lower have very little fat and are evaluated on degrees of muscle loss. The bone structure over the back and ribs is very visible, and another useful indicator is the area from the hooks to the pins. Cattle with muscle loss show a depressed or sunken appearance in this area. Cattle with condition scores of 6 or higher show a smoother appearance across the ribs and back. The breed type of cattle can influence where fat is deposited. Some cattle with Brahman breeding show very little fat over the ribs, but will deposit fat over the hooks and pins. Other cattle show uniform deposits of fat across the ribs and back, with no patchy deposits around the tail head. The BCS has been related to the fat cover and carcass fat by Texas and Oklahoma researchers (Herd and Sprott, 1986; Wagner et. al., 1988). A BCS range of 3 to 7 will include most beef cows in Florida. In slaughter trials, Texas and Oklahoma researchers have found that cows with body condition scores of 3, 5, and 7 had a carcass fat content of 7 to 9 percent, 15 to 18 percent, and 25 to 27 percent, respectively. A cow of medium frame size will weigh approximately 1100 pounds at BCS 5, but only 950 pounds at BCS 3. In

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Effects of Bod y Condition on Productivit y in Beef Cattle Pa g e 3March 1998this system, a medium-frame beef cow would changepercent, which was 20 to 28 percentage units lower in weight approximately 75 pounds for each conditionthan mature cows in BCS 3. Old cows (parity > 8) at score.BCS 3 and 4 also had lower pregnancy rates5 to 11 that maintaining BCS 5 or higher in young cows was Relationship to Pregnancy RateBody condition scores can be evaluatedTable 1. Description of Body Condition Scoresthroughout the year. The relationship of BCS at calving to reproduction has been looked at in several studies. A beef cow must conceive by 80 days after calving to maintain the 365-day calving interval desired in most management programs. Herd and Sprott (1986) reported 62 percent of beef cows with a BCS of 4 or lower at calving were in heat by 80 days after calving. Compare this to 88 percent and 98 percent for cows in BCS 5, or 6 or higher. Other studies have shown that cows with BCS below 5 require more services per conception, implying some depression in fertility of cycling beef cows. A summary of eight trials with over 1000 beef cows showed that cows with a BCS of 4 or lower, 5, or 6 or higher at calving had pregnancy rates of 61 percent, 79 percent, and 90 percent respectively (Table 2). The pregnancy rate for each condition score was variable from trial to trial, reflecting scoring differences among evaluators and other factors such as weight gain or loss after calving. However, the pregnancy rate improved in all trials when the BCS at calving improved from 4 to 5 and from 5 to 6. Cows with a higher BCS at breeding or pregnancy testing also showed improvements in pregnancy rate (Table 2). The BCS may vary 1 to 2 scores through the year on a herd of cows, but the thinner cows in a herd usually remain the thinner ones throughout the year. In three trials in Florida, the optimum BCS for cows evaluated at pregnancy testing appears to be 5 (Table 2). This appears to be one BCS lower than most of the research from Oklahoma and Texas and may be related to differences in the time of evaluation, the evaluators, or the type of cattle. Young cows (first 3 calves) that are thin have shown lower pregnancy rates than mature cows (Table 3). Young cows (parity 1, 2, 3) in BCS 4 at pregnancy testing had pregnancy rates of 50 to 60 percent, which was 12 to 22 percentage units lower than mature cows (parities 4 to 7) in BCS 4. Young cows in BCS 3 at pregnancy testing had pregnancy rates of 20 to 28 percentage unitsthan mature cows. This points out(BCS)aEmaciated ( BCS 1 ) Bone structure of shoulder, ribs, back, hooks and pins sharp to touch and easil y visible. Little evidence of fat deposits or musclin g Very Thin ( BCS 2 ) Little evidence of fat deposits but some musclin g in hind q uarters. The spinous processes feel sharp to the touch and are easil y seen, with space between them. Thin ( BCS 3 ) Be g innin g of fat cover over the loin, back and foreribs. Backbone still hi g hl y visible. Processes of the spine can be identified individuall y b y touch and ma y still be visible. Spaces between the processes are less pronounced. Borderline ( BCS 4 ) Foreribs not noticeable; 12th and 13th ribs still noticeable to the e y e, particularl y in cattle with a bi g sprin g of rib and ribs wide apart. The transverse spinous processes can be identified onl y b y palpation ( with sli g ht pressure ) to feel rounded rather than sharp. Full but strai g htness of musclin g in the hind q uarters. Moderate ( BCS 5 ) 12th and 13th ribs not visible to the e y e unless animal has been shrunk. The transverse spinous processes can onl y be felt with firm pressure to feel rounded not noticeable to the e y e. Spaces between the processes not visible and onl y distin g uishable with firm pressure. Areas on each side of the tail head are fairl y well filled but not mounded. Good ( BCS 6 ) Ribs full y covered, not noticeable to the e y e. Hind q uarters plump and full. Noticeable spon g iness to coverin g of foreribs and on each side of the tail head. Firm pressure now re q uired to feel transverse processes. Very Good ( BCS 7 ) Ends of the spinous processes can onl y be felt with ver y firm pressure. Spaces between processes can barel y be distin g uished at all. Abundant fat cover on either side of tail head with some patchiness evident. Fat ( BCS 8 ) Animal takin g on a smooth, block y appearance; bone structure disappearin g from si g ht. Fat cover thick and spon gy with patchiness likel y Very Fat ( BCS 9 ) Bone structure not seen or easil y felt. Tail head buried in fat. Animal's mobilit y ma y actuall y be impaired b y excess amount of fat. _______ Adapted from Herd and Sprott, 1986a

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Effects of Bod y Condition on Productivit y in Beef Cattle Pa g e 4March 1998even more important than in mature cows, and that thin, young cows have low pregnancy rates Regardless of whether the cows were scored at calving, breeding, or pregnancy testing, a higher BCS resulted in a higher pregnancy rate (Figure 2). This summary of 12 trials conducted in Florida, Texas, and Oklahoma with over 4000 beef cows, showed pregnancy rates improved for beef cows as BCS increased from 3 to 6. These data show a dramatic increase in pregnancy rate and that a BCS of 5 or higher was needed to achieve pregnancy rates above 90 percent.Critical BCS is 5Groups of cows with an average BCS of 4 or lower at calving, during the breeding season, or at pregnancy testing, had lower pregnancy rates compared to cows averaging BCS 5 or higher. BCS of 5 or higher resulted in good pregnancy rates provided other factors such as diseases were not reducing pregnancy rates. The relationship of BCS to calving interval showed that cows with a BCS of 5 or higherFigure 2 Relationship of bod y condition to pre g nanc y rate. Figure 3 Relationship between cow bod y condition score at matin g and subse q uent calvin g interval.had calving intervals of 365 days or less, and a BCS of 4 or lower resulted in calving intervals over 370 days (Figure 3). It is desirable for productive beef cows to have a BCS above 5 when this is accomplished through good pasture management programs with reasonable costs of production.Seasonal Changes in Condition ScoreThe body condition of the beef herd changes during the year. Body condition is usually highest in mid to late summer then declines in the fall or winter and is lowest in late winter or early spring. Loss of body condition during the fall and winter supplies nutrients that can reduce the amount of supplemental feed needed to maintain good pregnancy rates, calving intervals, and calf gains when cows are BCS 5 and above. The loss of 75 poundsfrom BCS 6 to 5is equivalent to the energy and protein in 250 pounds of shelled corn. At present prices, this is a savings of $15 or more per head in supplemental feed costs.

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Effects of Bod y Condition on Productivit y in Beef Cattle Pa g e 5March 1998 Table 2. Relationship of body condition score to pregnancy rate. Scoring Period Location Body Condition Scorea23456 ---------------------------------------Pre g nanc y rate, % ---------------------------------------------Condition scored at calving Texas----607691b cdOklahoma -12 63 82 88e dAvera g e-wei g hted ( for all trials ) --61 79 90 Condition scored during breeding season Texas --58 85 95cdCondition scored at pregnancy testing Deseret Ranch21417795--f g Nassau Count y --59 94 100 g cManatee Count y 44 56 39 3g hAvera g e ( all trials ) 13 43 66 94 -Bod y condition score 2=ver y thin, 3=thin, 4=borderline, 5=moderate, 6= g ood.aSummar y of 4 trials in Texas with over 1000 cows, Herd and Sprott, 1986.bCondition score 4 and below.cCondition score 6 and hi g her.dSummar y of 4 trials in Oklahoma with over 400 cows, Selk et al. ( 1986, 1988 ) Wettemann and Lusb y ( 1987 ) andeWettemann et al. ( 1987 ) Genho ( 1984 ) .fTrials conducted in Florida. g Condition score 5 or hi g her.hThe rate of loss of body condition should be gradual and moderate. If a cow can lose one condition score during the fall and winter (75 pounds of flesh), it is desirable for the cow herd to be supplemented to lose this gradually over 120 days instead of very rapidly in 45 days, then feeding high levels of supplemental feeds to try to prevent further condition losses. It is our observation that some Brahman and Brahman crossbred cattle will lose condition faster than other types of cattle, especially after calving. It is important that these cattle be monitored closely, and that forage and supplemental feeds be adjusted to avoid high rates of condition loss.Improving BCS in Thin CowsIt is desirable to have cows in BCS 5 or higher at calving, and if there is a considerable range in BCS in a herd, it is usually desirable to separate thin cows. In most situations, it is economically prohibitive to supplement the entire herd if only half of the cows will respond to the higher level of nutrition. An alternative is to separate thinner cows and manage these cows to improve BCS prior to calving. This should be done at or soon after weaning to allow 2 to 4 months prior to calving. These cows should be checked for internal parasites and dewormed if needed. The first option to consider is grazing the thin cows on higher quality pasture. The thin cows can graze the pastures first, then use the cows with higher

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Effects of Bod y Condition on Productivit y in Beef Cattle Pa g e 6March 1998BCS to clean up the residual forage. If additional supplements are needed to increase body condition in thin cows, it is suggested to feed a lower level over a longer period of time to get the most response to the supplement. Higher levels of supplement reduce forage intake and digestibility, and a higher proportion of the supplement replaces forage nutrients. Supplementing with high energy grain or molasses supplements to improve BCS is effective, but costs must be considered. To improve BCS from 4 to 5, a medium-frame-sized cow must gain approximately 75 pounds (Herd and Sprott, 1986) and requires approximately 350 pounds of TDN from high energy supplements in addition to forage. This will require an estimated 450 pounds of corn (4 to 5 pounds per cow per day) or 600 pounds of blackstrap molasses-based supplements (5 to 7 pounds per cow per day) fortified with protein in addition to ample quantities of maintenance quality pasture or hay feed over an 80 to 100-day period. At 1993 prices, the supplement would cost $35 to $40 or more per cow to improve the condition from BCS 4 to 5. These costs are significant; therefore to be cost effective, cattle must be grouped so that only pregnant cows in BCS 4 or below are fed this type and level of supplementation.EconomicsCows in lower BCS bring in significantly lower income from calves produced. Body Condition Score is related to pregnancy rate (Table 2), calving interval (Figure 3), calf age at weaning, and calf daily gain. Income estimates show the income per calf is reduced from $416 per calf for calves from BCS 5 cows to $359 per calf for calves from BCS 3 cows (Table 4). The income per cow is reduced $107 when BCS is decreased from 5 to 4 and $80 when BCS is decreased from 4 to 3. In contrast, the income per cow is reduced only $27 per cow when BCS is reduced from 6 to 5. Using strategies that cost less than $80 per cow for cows in BCS 3 and 4 will improve net income on many ranches. In the example cited in the previous section, the supplement cost $40 to increase the BCS from 4 to 5 between weaning and calving. The net income would increase $40 per cow over 18 months in this example. The increases in income from improving BCS will vary in different situations, and additional supplement needs to be critically evaluated to make sure that over $1 of income will be returned for each $1 in additional expenses. Table 3. Relationship of parity and body condition score to pregnancy rate, %.aParitybBody Conditon Scorec< 34> 5A l l 12 05 39 08 4 22 85 08 47 1 32 36 09 08 5 4 74 87 29 28 7 > 83 76 78 97 4 A l l3 16 08 98 2 Rae et al., 1993; Bod y condition scored at pre g nanc y testin g .aParit y is the number of calvin g opportunities, present a g e minus a g e at first calvin g (y ears ) .b Bod y condition scored at pre g nanc y testin g from 1 to 9, 3=thin, 4=borderline, 5=moderate.c

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Effects of Bod y Condition on Productivit y in Beef Cattle Pa g e 7March 1998 Table 4. Relationship of body condition score to beef cow performance and income. BodyCalvingCalfCalfYearly ConditionPregnancyInterval,WeaningCalf DailyCalf WeanPriceIncomeIncome ScoreRate, % days Age, days Gain, lb Weight, lb $/100 lb $/Calf $/cow abcdefgh3 434141901.60374 96359142 4 613812231.75460 86396222 5 863642401.85514 81416329 6 933642401.85514 81416356 Pre g nanc y rates avera g ed across trials when scored at calvin g breedin g and pre g nanc y testin g from Table 2.a Calvin g interval from Fi g ure 3.b Weanin g a g e is 240 da y s for cows in bod y condition scores 5 and 6 and decreases as calvin g intervals increase.c Dail y g ains based on observations. d Calculated as calf a g e times calf g ain plus birth wei g ht ( 70 lb ) .e Avera g e auction market price for similar wei g ht calves durin g 1991 and 1992.f Calculated as calf wei g ht times calf price. g Calculated as income/calf times pre g nanc y rate times .92 ( % calves raised of those pre g nant ) .hIf cows have a BCS above 5, it may be possible to Using BCS in Management DecisionsBody condition is affected by such factors as stocking rate, forage species, forage management, date of calving, weaning age, supplements, genetics, parasites, diseases, and weather to name a few. Strategies that result in BCS above 5, with little additional costs, will require less supplemental feed during the winter and lower costs of production. Managing the herd to improve BCS using supplementation strategies or other management techniques that provide a high return per dollar invested is a key factor in a profitable operation. A good ranch manager must evaluate many management options and adjust the program based on the current situation in each herd. Decisions such as stocking rate, fertilization, supplemental feeding, grouping of cattle, parasite control, and diagnosis of problems can use BCS to provide useful information about the overall nutritional status of the herd and individual cows in the herd. The type, level, and time of supplemental feeding should rely on the BCS of cattle. Forage quality and quantity, time of calving, body condition, milk production level, breed type, pasture size, and weather all must be considered. reduce the level of supplement provided. In other situations, the level of supplement given during the winter may need to be increased to maintain BCS. The amount of supplement usually needs to be adjusted to each herd, and it may need to be adjusted during the winter, depending on the conditions and cattle. An early frost or a drought can change the economically optimum levels of supplements. Body Condition Scores can help identify a problem within a herd. Results from 9 herds in Florida with over 4000 cows showed herd pregnancy rates varied from 61 to 92 percent (Table 5). Pregnancy rates for several herds were below 85 to 90 percent, which is considered to be both achievable and in the economically optimum range for herds using improved pastures. By evaluating the pregnancy rate at each condition score, the managers were able to determine if the below optimum pregnancy rate was explained by nutritional status (BCS), or other factors such as diseases or bulls.

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Effects of Bod y Condition on Productivit y in Beef Cattle Pa g e 8March 1998 Table 5. Relationship of herd, age and condition score to pregnancy rate, % Condition Scorea 2 3 4 5 6 7 ALL Locationb Manatee A40 21 46 94 --80 Manatee B-20 69 86 --82 Manatee C4 45 63 93 --75 Manatee D-8 32 79 --66 Manatee E-33 74 91 --88 Manatee F-75 82 94 --92 Manatee G--100 85 90 --89 Union 0 68 77 88 9010085 Alachua 0 6 49 81 9810061 Age, Yearsc 1 ---30 74 80 -73 2 --45 70 92 94 -82 3 --10 54 89 100-85 4 019 55 84 9510072 5 --20 66 91 93 -85 6 --38 69 89 100-84 7 1430 65 94 100-83 8 --80 78 94 100-91 9 --60 80 96 --90 10 854 78 93 --82 All Cattle 833 65 89 9210081 Condition scored at pre g nanc y testin g from 1 to 9, 2=ver y thin, 3=thin, 4=borderline, 5=moderate, 6= g ood,a7=ver y g ood. Over 4000 cows in 9 herds used in this evaluation, Location count y in Florida, Manatee A, B, C and D werebevaluated in 1989; Manatee E, F and G, Union and Alachua were evaluated in 1990. A g e at breedin g .cAs a rule of thumb, if cows in BCS 5 havepercent pregnancy rate. The average BCS for the over a 90 percent pregnancy rate, then factors suchherd was 4.3, and improving the BCS of cows with as reproductive diseases probably were not limitingBCS 2, 3 and 4 would be expected to improve the pregnancy rate, and improving BCS of thin cowspregnancy rate. Four of the nine herds evaluated should have improved the pregnancy rate of theshowed pregnancy rates below 90 percent for cows herd. In the Manatee C herd, the pregnancy rate in BCS 5 or above. In these herds, improving the was 75 percent, but cows with BCS 5 showed a 93 BCS of thin cows would be expected to improve

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Effects of Bod y Condition on Productivit y in Beef Cattle Pa g e 9March 1998pregnancy rate, but not necessarily to 85 to 90 percent. The Manatee D and Alachua herds Target a calving season that fits the forage, appeared to have lower pregnancy rates at all BCSsupplements, marketing plan, and compared to other herds, indicating factors that domanagement. not affect BCS were involved. Cull open and poorly producing cows. The age of each cow was determined by the year brand, and a summary revealed that heifers Control parasites and diseases. (age 1) and 4-year-old cows had the lowest pregnancy rates of all age groups when compared Provide a good mineral-free choice all year. across all herds (Table 5). The management and nutrition were different from herd to herd and an Provide 0.2 to 0.3 pounds per head per day evaluation of cow age is more useful within herds. of supplemental crude protein for cattle Manatee herds were bred at 2 years to calve at 3grazing forages with less than 7 percent crude years, and in 6 of the 7 herds, the pregnancy rateprotein or that have a TDN to crude protein was lowest (46 to 86 percent) for the 4-year-oldratio above 7. cows. There was some indication that 4-year-old cows were calving later in the calving season, Provide adequate protein for young cows to which would expectedly reduce their pregnancyimprove rebreeding. This may require rate. Even though the pregnancy rate of 3-year-oldmanaging first and second calf cows in cows rebreeding after their first calf was good (86separate herds during the winter. percent), if they were rebreeding late in the breeding season, this would result in later calving Group cattle by age and nutritional needs. as 4-year-old cows, and would likely lowerSeparate groups for weaned heifers, yearling pregnancy rate. In 7 of the 9 herds evaluated, thereheifers, first calf heifers and young cows and was a trend for BCS 3 and 4 cows nursing theiradult cows may be needed for part or all of the first or second calf to have lower pregnancy ratesyear. than older cows with similar BCS. In other words, when cows nursing their first or second calves Provide higher quality forages or higher were thin (BCS 3 or 4) they had lower pregnancylevels of energy supplements balanced with rates than thin, mature cows.protein to reduce weight loss or improve BCS when cow BCS is below 5. An evaluation of the relationship of pregnancy rate to BCS and age does not pinpoint the exact problem in a herd, but it certainly helps a manager eliminate some possibilities and focus attention on management factors that are important and can help improve production and profit.Management Strategies to Improve BCSA good ranch manager must evaluate many different options when deciding the ranch management program. Several management strategies that may help maximize profit follow. Adjust stocking rate to ensure adequate forage during the stocking rate limiting months.SummaryGood reproductive performance requires a BCS of 5 or higher at calving and through breeding. Proper stocking rates, a good mineral supplementation program, and timely use of protein supplements offer the most potential for economically improving body condition and pregnancy rates. Separating cows by condition at pregnancy testing or two to three months prior to calving and feeding both groups to calve in BCS 5 or above will maintain high reproductive performance while holding supplemental feed costs to a minimum. The routine use of BCS in each herd will provide needed information to manage the cow herd for a high calf crop and profitability.

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Effects of Bod y Condition on Productivit y in Beef Cattle Pa g e 10March 1998 Body Condition Score 5 (Desirable Condition) Body Condition Score 1 Body Condition Score 3 Body Condition Score 2 Body Condition Score 4

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Effects of Bod y Condition on Productivit y in Beef Cattle Pa g e 11March 1998 Body Condition Score 6 Body Condition Score 8 Body Condition Score 7 Body Condition Score 9

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Effects of Bod y Condition on Productivit y in Beef Cattle Pa g e 12March 1998ReferencesGenho, P. 1984. Body condition and nutrition level on the reproduction at Deseret ranch. Proc. Thirty-third Beef Cattle Short Course, pp. 57. Herd, D. B. and L. R. Sprott. 1986. Body condition, nutrition, and reproduction of beef cows. Texas Agricultural Extension Service Bulletin B1526. Kilkenny, J. B. 1978. Reproductive performance of beef cows. World Review Animal Prod. 14:3. Rae, D. O., W. E. Kunkle, P. J. Chenoweth, R. S. Sand and T. Tran. 1993. Relationship of parity and body condition score to pregnancy rates in Florida beef cattle. Theriogenology 39:1143. Selk, G. E., R. P. Wettemann, K. S. Lusby and R. T. Rusby. 1986. The importance of body condition at calving on reproduction in beef cows. Animal Science Research Report, pp. 316, Oklahoma State Univ. Selk, G. E., R. P. Wettemann, K. S. Lusby, J. W. Oltjen, S. L. Mobely, R. J. Rusby and J. C. Garmendia. 1988. Relationships among weight change, body condition and reproductive performance of range beef cows. J. Animal Sci. 66:3153. Wagner, J. J., K. S. Lusby, J. W. Oltjen, J. Rakestraw, R. P. Wettemann, and L. E. Walters. 1988. Carcass composition in mature Hereford cows: estimation and effect on daily metabolizable energy requirement during winter. J. Animal Sci. 66:603. Wettemann, R. P. and K. S. Lusby. 1987. Body condition at calving, calf survival and reproductive performance of first calf heifers. Animal Science Research Report, pp. 73, Oklahoma State Univ. Wettemann, R. P. K. S. Lusby, R. T. Rusby and M. W. Richards. 1987. Body condition at calving and post partum intake influence reproductive performance of range cows. Animal Science Research Report, pp. 70, Oklahoma State Univ.