Gorewit R C, Gassman K B
J Dairy Sci. 1985 Jul;68(7):1813-8. doi: 10.3168/jds.S0022-0302(85)81031-6.
For effects of varying duration of premilking manual udder massage on milking performance and oxytocin release, five Holstein cows were subjected to a) no stimulation, b) stimulation by manual udder massage before machine attachment for 15 s, c) for 30 s, d) for 60 s, and e) for 120 s. Milk yield, fat, protein, and somatic cell content were not affected by treatments. The 30-, 60-, and 120-s treatments resulted in higher peak milk flow rate as compared to no stimulation. Stimulation for 60 or 120 s did not achieve higher peak milk flow rates than 15 or 30 s. Average milk flow rate increased with duration of stimulation, and no stimulation differed from 30-, 60-, and 120-s treatments. Machine-on time decreased with increasing stimulation. However, differences in average flow rates and machine-on times became nonsignificant when premilking stimulation time was added to machine-on time. No differences were significant between treatments and mean oxytocin concentrations. The marked difference in milk flow variables and machine-on time suggested a small yet finite threshold concentration of oxytocin leads to milk ejection. Udder massage of 30 s prior to machine attachment is more than adequate for preparing cows for milking with machine stripping.
为研究挤奶前手工乳房按摩持续时间不同对挤奶性能和催产素释放的影响，对5头荷斯坦奶牛进行了以下处理：a) 无刺激；b) 在机器附着前进行15秒的手工乳房按摩刺激；c) 进行30秒刺激；d) 进行60秒刺激；e) 进行120秒刺激。产奶量、脂肪、蛋白质和体细胞含量不受处理的影响。与无刺激相比，30秒、60秒和120秒的处理导致更高的峰值奶流率。60秒或120秒的刺激并未比15秒或30秒的刺激获得更高的峰值奶流率。平均奶流率随刺激持续时间增加，无刺激与30秒、60秒和120秒的处理不同。机器开启时间随刺激增加而减少。然而，当将挤奶前刺激时间加到机器开启时间上时，平均流速和机器开启时间的差异变得不显著。各处理与平均催产素浓度之间无显著差异。奶流变量和机器开启时间的显著差异表明，催产素的一个小但有限的阈值浓度会导致乳汁排出。在机器附着前进行30秒的乳房按摩足以让奶牛为机器挤奶做好准备。
