Triplett B L, Neuendorff D A, Randel R D
Texas Agricultural Experiment Station, Overton 75684-0290, USA.
J Anim Sci. 1995 Nov;73(11):3223-9. doi: 10.2527/1995.73113223x.
Eighty first-calf Brahman heifers and 51 mature Brahman cows were allotted to one of three diets based on parity, sex of calf, and breed of calf sire (Angus, Brahman, or Tuli) to evaluate rumen undegraded intake protein's (UIP) influence on production characteristics and reproductive performance. Supplements contained either 38.1% (low), 56.3% (medium), or 75.6% (high) UIP. Supplements were given from d 7 to 119 after calving to dams grazing rye-ryegrass overseeded Coastal bermudagrass pastures and with access to Coastal bermudagrass hay. Dam and calf BW and dam body condition score were recorded on d 7, 35, 63, 91, and 119 after calving. Four-hour milk production was recorded on the above days for low (n = 18), medium (n = 19), and high (n = 18) UIP animals and on d 7 and 35 for the entire group. Blood for progesterone RIA was drawn weekly and on d 6, 8, 10, and 12 after an observed estrus. Medium UIP heifers produced more (P < .02) milk (1.18 +/- .07 kg/4 h) than high UIP heifers (.94 +/- .07 kg/4 h), but milk production in mature cows was not influenced by diet. Low UIP dams had lower (P < .04) first-service conception rates (29.2%) than medium (57.6%) and tended (P < .10) to have lower rates than high UIP dams (54.6%). Overall pregnancy rates tended (P < .10) to be higher in medium (61.5%) and high (56.4%) UIP groups than in the low (43.2%) UIP group. Supplementing UIP at the medium rate improved first-service conception rates and tended to improve pregnancy rates.
根据胎次、犊牛性别以及犊牛父亲的品种（安格斯、婆罗门或图利），将80头初产婆罗门小母牛和51头成年婆罗门母牛分配到三种日粮之一，以评估瘤胃非降解摄入蛋白（UIP）对生产性能和繁殖性能的影响。补充料中UIP含量分别为38.1%（低）、56.3%（中）或75.6%（高）。产后第7天至119天，给在黑麦-黑麦草混播的滨海百慕大草场上放牧且可采食滨海百慕大干草的母牛投喂补充料。在产后第7天、35天、63天、91天和119天记录母牛和犊牛的体重以及母牛的体况评分。在上述日期，对低UIP组（n = 18）、中UIP组（n = 19）和高UIP组（n = 18）的母牛记录4小时产奶量，对整个群体在产后第7天和35天记录4小时产奶量。每周以及在观察到发情后的第6天、8天、10天和12天采集血液用于孕酮放射免疫分析。中UIP组小母牛的产奶量（1.18±0.07千克/4小时）高于高UIP组小母牛（0.94±0.07千克/4小时）（P < 0.02），但成年母牛的产奶量不受日粮影响。低UIP组母牛的首次输精受胎率（29.2%）低于中UIP组（57.6%）（P < 0.04），且低于高UIP组母牛（54.6%）的趋势（P < 0.10）。总体而言，中UIP组（61.5%）和高UIP组（56.4%）的妊娠率高于低UIP组（43.2%）的趋势（P < 0.10）。以中等水平补充UIP可提高首次输精受胎率，并倾向于提高妊娠率。
