Skarda J, Slaba J, Krejcí P, Mikulás I
Institute of Animal Physiology and Genetics, Czechoslovak Academy of Sciences, Prague.
Physiol Res. 1992;41(2):151-5.
The effects of administration of recombinantly derived bovine somatotropin (somidobove) in a sustained-release vehicle on the profiles of concentrations of bovine somatotropin (bST) in the blood plasma and on the milk yield of dairy cows of three herds were examined. Cows (36-87 days post partum) were treated subcutaneously with recombinant bST at 28-day intervals. In control animals, basal concentrations of bST averaged 1.4 ng.ml-1 in first-calf heifers and 1.5 ng.ml-1 in multiparous cows. In somidobove treated first-calf heifers, the concentration of bST was increased to 10.7, 14.5, and 27.0 ng.ml-1 at 24 h postinjection and in multiparous cows to 6.6, 11.0, and 11.7 ng.ml-1 on day 2 postinjection of 320, 640, and 960 mg of somidobove, respectively. On day 8 postinjection the average plasma bST levels of both parity groups are similar (on the average 3.4, 8.6, and 12.5 ng.ml-1 for three doses of somidobove respectively) and for the two highest doses being still significantly increased. During the 2nd week postinjection plasma bST concentration declined returning to control levels on day 15 postinjection. Somidobove-treated first-calf heifers produced 10.9, 16.7 and 17.9% and multiparous animals 25.5, 24.2 and 32.5% more milk than the controls when given 320, 640 and 960 mg somidobove, respectively. The cyclic pattern in milk yield within each 28-day injection interval was observed consistently in all herds. The milk yield increased to a maximum between day 4 to 8 postinjection and then slowly declined. Milk composition was not affected by somidobove treatment.
研究了以缓释载体形式给予重组牛生长激素（索米多牛生长激素）对三个牛群奶牛血浆中牛生长激素（bST）浓度曲线以及产奶量的影响。对产后36 - 87天的奶牛每隔28天进行一次重组bST皮下注射治疗。在对照动物中，初产小母牛的bST基础浓度平均为1.4 ng/ml，经产母牛为1.5 ng/ml。在接受索米多牛生长激素治疗的初产小母牛中，注射后24小时bST浓度分别增加到10.7、14.5和27.0 ng/ml，在经产母牛中，注射320、640和960 mg索米多牛生长激素后第2天分别增加到6.6、11.0和11.7 ng/ml。注射后第8天，两个胎次组的平均血浆bST水平相似（分别给予三剂索米多牛生长激素时平均为3.4、8.6和12.5 ng/ml），且两个最高剂量仍显著升高。注射后第2周，血浆bST浓度下降，在注射后第15天恢复到对照水平。当分别给予320、640和960 mg索米多牛生长激素时，接受索米多牛生长激素治疗的初产小母牛产奶量比对照多10.9%、16.7%和17.9%，经产母牛多25.5%、24.2%和32.5%。在所有牛群中，每个28天注射间隔内的产奶量循环模式均一致被观察到。产奶量在注射后第4至8天增加到最大值，然后缓慢下降。索米多牛生长激素治疗对牛奶成分没有影响。
