Jacquemet N, Prigge E C
Division of Animal and Veterinary Sciences, West Virginia University, Morgantown 26506-6108.
J Dairy Sci. 1991 Jan;74(1):109-14. doi: 10.3168/jds.S0022-0302(91)78150-2.
Six lactating dairy goats were utilized in a replicated 3 x 3 Latin square design to examine the effect of increased postmilking prolactin concentrations on lactational performance. Thirty minutes after each milking, either placebo or pituitary-derived ovine prolactin at 2 mg/h or 4 mg/h was infused via jugular cannula for 2 h. Goats were housed in a controlled environment at 19 degrees C and a cycle of 16 h light and 8 h dark. Mean plasma prolactin concentrations after milking were increased 100 and 180% for 2 and 4 mg/h prolactin infusion, respectively. Milk yield was slightly but significantly increased by 2 mg/h prolactin infusion compared with placebo and 4 mg/h prolactin infusion. However, milk composition and yields of milk components were not influenced by treatments. No differences in dry matter intake, digestibility of the diet, or N retention were observed. Circulating concentrations of glucose, nonesterified fatty acids, insulin, and glucagon were not altered.
选用6只泌乳期奶山羊，采用重复3×3拉丁方设计，研究挤奶后催乳素浓度升高对泌乳性能的影响。每次挤奶后30分钟，通过颈静脉插管注入安慰剂或垂体来源的绵羊催乳素，剂量分别为2毫克/小时或4毫克/小时，持续2小时。奶山羊饲养在温度为19摄氏度、光照16小时黑暗8小时的可控环境中。与安慰剂组相比，催乳素注入量为2毫克/小时和4毫克/小时时，挤奶后平均血浆催乳素浓度分别升高了100%和180%。与安慰剂组和4毫克/小时催乳素注入组相比，2毫克/小时催乳素注入组的产奶量略有但显著增加。然而，奶的成分和各成分产量不受处理影响。干物质摄入量、日粮消化率或氮保留量均无差异。葡萄糖、非酯化脂肪酸、胰岛素和胰高血糖素的循环浓度未发生改变。
