Beckett S, Lean I, Dyson R, Tranter W, Wade L
Department of Animal Science, University of Sydney, Camden, New South Wales, Australia.
J Dairy Sci. 1998 Jun;81(6):1563-73. doi: 10.3168/jds.S0022-0302(98)75722-4.
A randomized clinical trial including 1109 cows from 12 Australian dairy herds was used to evaluate the effects of monensin on the health (n = > 686 cows), production (n = 915 cows), and reproduction (n = > 908 cows) of dairy cows. Cows were allocated to a treatment group receiving a slow-release intraruminal bolus containing 32 g of sodium monensin that was administered 40 d before and 50 d following the anticipated calving date or to a control group. Treatment did not significantly alter any reproductive outcome; 54.5% of cows treated with monensin and 58.2% of control cows were pregnant at first service, and days to conception were lower for cows treated with monensin. The hazard rate (0.95) was not significant for these cows. The percentage of cows pregnant was 83.8 for control cows, and days to first estrus (hazard rate = 1.04) and first service (hazard rate = 1.04) were not significantly higher for treated cows. Treatment with monensin did not significantly alter the risk of any disease. The incidence of retained fetal membranes, pyometra, lameness, abortion, and infectious diseases was not significantly lower for cows in the treatment group, and the incidence of mastitis was not significantly higher for cows in the treatment group. Monensin significantly increased milk production by 0.75 L/d per cow and tended to increase milk fat and protein yields but had no significant effect on milk fat or milk protein percentages. Changes in the production of milk and milk constituents were consistent throughout lactation.
一项随机临床试验纳入了来自澳大利亚12个奶牛场的1109头奶牛，用于评估莫能菌素对奶牛健康（n = > 686头奶牛）、生产性能（n = 915头奶牛）和繁殖性能（n = > 908头奶牛）的影响。奶牛被分配到治疗组或对照组，治疗组接受一种含32克莫能菌素钠的缓释瘤胃丸剂，在预计产犊日期前40天和产后50天给药。治疗并未显著改变任何繁殖结果；接受莫能菌素治疗的奶牛中54.5%在首次配种时怀孕，对照组奶牛为58.2%，且莫能菌素治疗的奶牛受孕天数更低。这些奶牛的风险率（0.95）不显著。对照组奶牛的怀孕百分比为83.8%，治疗组奶牛首次发情（风险率 = 1.04）和首次配种（风险率 = 1.04）的天数并未显著增加。莫能菌素治疗并未显著改变任何疾病的风险。治疗组奶牛胎膜滞留、子宫积脓、跛足、流产和传染病的发生率并未显著降低，治疗组奶牛乳腺炎的发生率也未显著升高。莫能菌素使每头奶牛的日产奶量显著增加0.75升，且有增加乳脂和乳蛋白产量的趋势，但对乳脂或乳蛋白百分比没有显著影响。整个泌乳期牛奶和牛奶成分产量的变化是一致的。
