Prichard D L, Hargrove D D, Olson T A, Marshall T T
University of Florida, Gainesville 32611.
J Anim Sci. 1989 Mar;67(3):609-16. doi: 10.2527/jas1989.673609x.
A 2-yr study was conducted to evaluate the effects of a high-energy creep feed, preweaning zeranol implants and breed type on calf and cow performance. Two hundred calves sired by Brahman and Romana Red bulls out of Angus and Angus x Brown Swiss reciprocal crossbred (F1) dams were stratified by breed type and sex to three creep treatments: no creep feed (NC); long-term creep (LC), creep-fed from 56 to 210 d of age (weaning); and short-term creep (SC), creep-fed from 146 to 210 d of age. Alternate calves within sex, breed type and creep treatment were implanted with 36 mg of zeranol at an average of 56 d and reimplanted 90 d later. The LC and SC calves had heavier (P less than .001) 210-d weights than NC calves (264 and 257 vs 231 kg, respectively), and the LC calves were heavier (P less than .001) at 146 d than NC calves. The LC calves had higher (P less than .001) ADG from 118 to 210 d of age and higher 146 and 210-d condition scores than did NC calves. Pregnancy rate was not affected (P greater than .46) by creep treatment of calf. Zeranol implants increased (P less than .01) 146- and 210-d weights (184 vs 175 kg and 259 vs 243 kg) and ADG during all periods to weaning. Brahman-sired calves had higher (P less than .005) 146- and 210-d weaning weights and frame scores than Romana Red-sired calves.(ABSTRACT TRUNCATED AT 250 WORDS)
开展了一项为期两年的研究，以评估高能犊牛补饲、断奶前玉米赤霉醇植入以及品种类型对犊牛和母牛生产性能的影响。由婆罗门牛和罗曼纳红牛与安格斯牛及安格斯×瑞士褐牛正反交杂种（F1）母牛所生的200头犊牛，按品种类型和性别分为三种犊牛补饲处理组：不补饲（NC）；长期补饲（LC），从56日龄至210日龄（断奶）进行补饲；短期补饲（SC），从146日龄至210日龄进行补饲。在性别、品种类型和补饲处理组内，每隔一头犊牛在平均56日龄时植入36毫克玉米赤霉醇，并在90日后再次植入。LC组和SC组犊牛的210日龄体重比NC组犊牛更重（P＜0.001）（分别为264千克和257千克对231千克），且LC组犊牛在146日龄时比NC组犊牛更重（P＜0.001）。LC组犊牛在118日龄至210日龄期间的平均日增重更高（P＜0.001），且146日龄和210日龄时的体况评分比NC组犊牛更高。犊牛的补饲处理对妊娠率没有影响（P＞0.46）。玉米赤霉醇植入增加了（P＜0.01）146日龄和210日龄时的体重（分别为184千克对175千克和259千克对243千克）以及断奶前各阶段的平均日增重。婆罗门牛所生犊牛的146日龄和210日龄断奶体重及体躯评分比罗曼纳红牛所生犊牛更高（P＜0.005）。（摘要截选至250词）
