A Body Condition Scoring Chart for Holstein Dairy Cows

Three hundred and seventy two horses of varying breeds, height and fatness were weighed and measured for height at the withers. They were assessed for condition score by adaptation of a previously published method. The heart girth and length of 281 of the horses were also measured. Weight of horses was highly correlated (P less than 0.001) with height (r2 = 0.62), condition score (r2 = 0.22) and girth2 x length (r2 = 0.90). Nomograms were constructed to predict weight from height and condition score, and girth and length measurements. Weight can also be accurately estimated from the formula: (formula, see text) The average value of 'Y' in this experiment was 11900 and this estimated weight with more accuracy than some previously published values of 'Y'. Racing Thoroughbred horses were found to be significantly lighter than non-racing Thoroughbreds of the same height and condition score. The method of assessment of condition score was shown to be repeatable between different operators with varying degrees of experience.

Body condition scoring and weight estimation of horses.

Body weight and condition score, although perhaps imprecise or subjective, are functional indicators of energy status and rebreeding performance after calving. Inadequate precalving and(or) postcalving energy or protein nutrition lowers pregnancy rates as well as first-service conception rates and extends postpartum intervals in suckled postpartum beef females. Normal nutritional regimens for dairy cows that are fed for maximal lactation do not exhibit long postpartum intervals or reduced fertility. Yet excessive protein intake may depress postpartum rebreeding performance, especially in older dairy cows. Feeding of ionophores, with increased ruminal propionate levels in the rumen, results in an earlier return to estrus postpartum. Underfeeding of the postpartum cow extends the period of ovarian inactivity. The underfed postpartum cow's lack of ovarian activity appears to be due to a suppression of the pulsatile release of LH from the anterior pituitary gland, which in turn is controlled by release of GnRH from the hypothalamus. Some metabolic compound(s) presumably act on the hypothalamic-pituitary-ovarian axis as the nutritional state of the animal is altered.

Nutrition and postpartum rebreeding in cattle

Effects of nutrition and metabolic status on circulating hormones and ovarian follicle development in cattle

Effects of body condition score (BCS) at parturition and postpartum weight gain on reproduction and production responses were evaluated using 240 primiparous (21 to 28 mo) beef cows calving in 60-d periods in three states over 3 yr. Cows were randomly allotted 90 d before parturition and fed to achieve BCS of 4, 5, or 6 (1=emaciated, 9=obese) at parturition. After parturition, one-half of these cows (within state) were group-fed to gain.45 kg/d (moderate) or.90 kg/d (high) until the start of a 60-d breeding season. Cows calving in BCS of 4, 5, or 6, respectively, had calves with progressively heavier (P<.05) birth weights, but dystocia score was not influenced by BCS at calving. Parturient BCS of cows had no effect on actual or 205-d adjusted weaning weights of calves. Birth weights, dystocia score, and actual and 205-d adjusted weaning weights were affected by location (P<.05). Cows with greater weight gains postpartum had calves with heavier (P<.05) actual and 205-d adjusted weaning weights than did cows with moderate weight gains. No significant interactions among location, BCS, or postpartum nutrition-group were observed for any of the production variables described above. Greater BCS at calving resulted in more (P<.05) cows in estrus and more (P<.05) cows pregnant by 40 and 60 d of a breeding season. Luteal activity by start of breeding, as well as estrus responses and pregnancy rates at 20, 40, or 60 d of a breeding season, were affected by location (P<.05). Greater postpartum weight gain increased (P<.05) luteal activity by start of breeding and estrus responses and pregnancy rates at 20, 40, and 60 d of a breeding season. These results indicate that primiparous beef cows calving with greater BCS have heavier calves at birth without increased dystocia. More cows calving with greater BCS also exhibit estrus and become pregnant in a finite breeding season. Postpartum weight change seems to have a further additive effect on estrus responses and pregnancy rates and increases actual and adjusted 205-d weaning weights of calves

Reproductive responses and calf birth and weaning weights as affected by body condition at parturition and postpartum weight gain in primiparous beef cows.

M. W. Richards

Papers

Effect of Varying Levels of Postpartum Nutrition and Body Condition at Calving on Subsequent Reproductive Performance in Beef Cattle