The effect of cow udder score on cow/calf performance in the Nebraska Sandhills

摘要

Poor udder and teat confirmation decreases profitability due to decreased calf weaning weight, increased incidence of mastitis and labor, and decreased cow lifetime productivity. Therefore, the objective of this retrospective study was to evaluate the effect of beef cow udder score on cow performance and pre- and postweaning progeny performance. In a 5-yr study, crossbred cows at the Gudmundsen Sandhills Laboratory, Whitman, NE, were assigned an udder score each year at calving, from 1 to 5, using an udder and teat combination score. Cows were grouped by udder scores and classified as either low udder score (LUS, udder score 1 or 2; = 223) or high udder score (HUS, udder score 3 or 4; = 1,742). The udder score combines udder conformation and a teat scoring system. Low udder scores consisted of pendulous udders and large teats, whereas HUS consisted of tight udders and small, symmetrical teats. Mixed models were used to evaluate udder score on cow performance and calf pre- and postweaning performance. Cow body weight (BW) at prebreeding and weaning was greater ( < 0.01) in LUS cows compared with HUS counterparts. Pregnancy rate was not different ( = 0.35) between udder classification groups. Calf BW at birth ( = 0.95), weaning ( = 0.40), and adjusted 205-d BW ( = 0.28) were not different between udder groups. Cow udder score did not influence feedlot entry ( = 0.41) and final BW ( = 0.30), dry matter intake ( = 0.53), average daily gain ( = 0.60), and gain:feed ratio ( = 0.85) of steer progeny. However, steers from HUS dams had greater hot carcass weight (HCW; = 0.04) and backfat thickness ( = 0.02) compared with LUS counterparts. Results from this study suggest cows with less desirable udder structure may not have a negative impact on calf preweaning growth and performance; however, backfat thickness and HCW in the finishing phase were lower in steers from cows with a lower udder score.