Insulin-like growth factor-I (IGF-I) is a polypeptide that has the function of regulating the expression of steroid hormones through endocrine, paracrine, and autocrine actions in reproductive organs. Moreover, IGF-I is involved in ovulation, implantation, maintenance of pregnancy, and development of fetuses in animals. Therefore, this study was conducted to investigate the effects of serum IGF-I concentration on progesterone (P4) concentration and pregnancy rates in Korean native cattle (Hanwoo). Blood was collected at estrus (Day 0) and Day 11. Artificial insemination was performed at Day 0. Serum IGF-I and P4 concentrations were measured by radioimmunoassay (RIA). Overall, P4 concentration was higher at Day 11 than Day 0, whereas the pattern of IGF-I concentration was reversed. When animals were divided into two groups depending on the pregnancy status, P4 concentrations of the pregnant group was significantly higher than that of the non-pregnant group at Day 0 (p<0.05) and Day 11 (p<0.05). But, lower IGF-I concentrations were detected in the pregnant group at Day 0 (p<0.05) and Day 11 (p<0.05) compared to the non-pregnant group. In conclusion, these results indicated that serum IGF-I is inversely associated with P4 concentration during early pregnancy in Hanwoo.
|Number of pages||4|
|Journal||Asian-Australasian Journal of Animal Sciences|
|Publication status||Published - 2003 Feb 1|
- Early Pregnancy
- Korean Native Cattle
ASJC Scopus subject areas
- Animal Science and Zoology