TY - JOUR JO - Journal of Animal and Feed Sciences J2 - J. Anim. Feed Sci. SN - 1230-1388 VL - 17 IS - 4 PY - 2008 ID - Miao2008 TI - Age-related changes of serum leptin, insulin, IGF-I and thyroid hormones levels in growing Jinhua and Landrace gilts AB - The present study was aimed to investigate the age-related changes of the serum IGF-I, leptin, insulin, triiodothyronine (T 3 ) and thyroxine (T 4 ) levels in pigs of different breeds. Jinhua and Landrace gilts were sampled at 35, 80 and 125 days of age, respectively. Serum hormone levels were measured with RIA. Serum IGF-I, leptin levels increased with age and displayed breed differences. Jinhua gilts showed lower (P<0.05) serum IGF-I and higher (P<0.05) leptin levels compared with Landrace gilts. In contrast, serum T 3 , T 4 levels decreased with age, Jinhua gilts had lower serum T 4 levels at 80 days of age. Meanwhile, Jinhua gilts had higher (P<0.01) serum insulin levels. Serum leptin, IGF-I, insulin and T 4 levels correlated with carcass fat content (P<0.05), which suggested that the breed differences of serum hormone levels may contribute to the different phenotypes in adipose tissue deposition. AU - Miao, Z. G. AU - Wang, L. J. AU - Xu, Z. R. AU - Han, X. Y. AU - Quan, H. Z. AU - Li, G. W. SP - 548 EP - 558 DA - 2008 DO - 10.22358/jafs/66683/2008 UR - https://doi.org/10.22358/jafs/66683/2008 ER -