外因性 GH의 投與를 통한 韓牛의 成長 및 乳腺의 發達 = Effect of rGH on Body Growth and Mammary Gland Development on Korean Native Heifers

국문 초록 (Abstract)

위인성 성장호르몬(rGH)을 14일 간격으로 두당 250mg씩 한우 암송아지(8-12개월령. 160-240kg)에 대한 투여한 후 내인성 성장호르몬, estrogen IGF-I, 체중, 유두용적의 변화 및 IGFBP_3에 대한 processing enzyme의 활성정도를 파악하고져 28일 간격으로 1994년 12월부터 다음해 2월까지 본 연구를 실시하였다.
GH 혈청농도는 처리구가 무처리구에 비해 rGH는 투여후 시간이 경과함에 따라 현저히 증가 하였고(p<.01). estrogen과 IGF-I도 처리 후 8주째(P<.05)에 증가를 보였다. 또한 체중(P<.01)과 유두용적(P<.05)도 투여 8주째에 증가를 보였다. 외인성 성장호르몬(rGH)의 投與前에 processing enzyme의 활성이 낮았으나, 250mg의 rGH 투여 후에는 processing enzyme의 활성이 실험기간 내내 현저히 증가하는 것으로 나타났다.
본 연구결과 외인성 성장호르몬은 한우암송아지의 내인성 호르몬 변화를 통하여 성장 및 유선발육을 증진 시킬수 있다는 것을 제시하여 주었다.

다국어 초록 (Multilingual Abstract)

This experiment was carried out with 12 Korean native heifers(8-12 mth old : body weight, 160-240kg) raised at a farm of Chang-Soo Livestock Cooperatives to evaluate the effects of rGH(recombinant growth hormone) on serum concentrations of growth hormone, estrogen, and IGF-I. weight gain teat volume gain and processing enzyme activity of IGF-I binding protein Ⅲ at 28 day intervals. Animals used were injected with 250mg rGH at 14 day intervals from December. 1994 to February, 1995. The significant difference was found in the group of treatment on the 4th week in the endogenous GH(p<.01) and 8th week in estrogen and IGF-I(p<.05) after injection of rGH in Korean native heifers. There were significant differences between control and treatment group in weight and teat volume on 8th week after treatment(P<.05). Processing enzyme activity before injection of rGH was low. However heifers injected with 250mg of rGH showed that processing enzyme activity of IGF binding protein was highly increased throughout the experiment. Present results suggest that injection of exogenous rGH to heifers can increase the growth performance and mammary gland development of Korean native heifers by the endogenous hormonal changes.