Buonomo F C, Baile C A
Monsanto Company, Animal Science Division, St. Louis, MO 63198.
Domest Anim Endocrinol. 1988 Jul;5(3):219-29. doi: 10.1016/0739-7240(88)90033-1.
Recombinant bovine somatotropin (rbGH) was administered by subcutaneous injection at daily doses of 0.5 or 2.5 mg/kg for a two week period in female broiler chicks between 4 and 6 weeks of age. Half of the chicks received dietary corticosterone at a 1 ppm level. Growth rate was significantly increased 6.1% and 6.9% following one week of treatment with 0.5 or 2.5 mg/kg rbGH respectively. Treatment with the same respective doses of rbGH in the presence of 1 ppm corticosterone, supplied to suppress any possible immune response elicited by the heterologous somatotropin, resulted in an 8.0% and 7.8% increase (P less than .05) in growth rate during the first week of treatment. The rbGH-associated increase in growth rate was accompanied by a significant increase in food intake, higher circulating levels of IGF-I, and lower plasma T4 concentrations, while plasma T3 levels were unchanged. All effects were attenuated during the second week of treatment, concomitant with the development of high antibody titer against rbGH regardless of dietary corticosterone administration. Carcass parameters relating to bone, muscle and fat were not different between rbGH-treated and control chickens at the end of the two week treatment period. Thus rbGH is capable of stimulating a short-term improvement in growth rate, which is related to increased feed consumption and is of limited duration.
对4至6周龄的雌性肉鸡雏鸡皮下注射重组牛生长激素（rbGH），每日剂量为0.5或2.5毫克/千克，持续两周。一半雏鸡日粮中添加1 ppm的皮质酮。分别用0.5或2.5毫克/千克rbGH处理一周后，生长速率显著提高了6.1%和6.9%。在1 ppm皮质酮存在的情况下使用相同剂量的rbGH进行处理，以抑制由异源生长激素引发的任何可能的免疫反应，在处理的第一周生长速率提高了8.0%和7.8%（P小于0.05）。与rbGH相关的生长速率增加伴随着采食量显著增加、循环中IGF-I水平升高以及血浆T4浓度降低，而血浆T3水平未改变。在处理的第二周，所有这些效应均减弱，同时无论日粮中是否添加皮质酮，均出现了针对rbGH的高抗体滴度。在两周处理期结束时，接受rbGH处理的鸡与对照鸡在与骨骼、肌肉和脂肪相关的胴体参数方面没有差异。因此，rbGH能够刺激生长速率的短期提高，这与采食量增加有关，且持续时间有限。
