Abstract: In order to explore the correlation between calf birth weights and expression level of adiponectin, leptin, IGF-1 in cow's venous and cord venous blood. Fifty-four healthy Chinese Holstein cows that experienced normal natural birth were used, and were divided into 3 groups based on calf birth weights (A, ≤40 kg; B, 40~45 kg; C, ≥45 kg). The cow's venous blood and cord venous blood was collected. ELISA was used to evaluate the expression levels of adiponectin, leptin and IGF-1 to analyze the correlation among them as well as correlation with calf birth weights. It was shown that there were significant (P<0.01) correlations among adiponectin, leptin and IGF-1 in cow's venous blood, while these indexes showed no significant (P>0.05) correlations with calf birth weights. In cow's cord venous blood, adiponectin, leptin, and IGF-1 were significantly (P<0.01) correlated, and adiponectin, leptin, and IGF-1 in cord venous blood as whole were positively correlated with calf birth weights, and was significantly (P<0.01) correlated with calf birth weights individually. Adiponectin, leptin, and IGF-1 expression levels in venous blood were significantly (P<0.01) higher than those in cord venous blood, and were not significantly (P>0.05) correlated with those in cord venous blood. The results showed that there were adiponectin, leptin, and IGF-1 in venous blood and cord venous blood. Adiponectin, leptin, and IGF-1 in venous and cord venous blood were potentially inter-regulated with each other. Adiponectin, leptin, and IGF-1 expression levels in venous blood were not significantly (P<0.05) correlated with calf birth weights, while adiponectin, leptin, and IGF-1 expression levels in cord venous blood were significantly (P<0.01) correlated with calf birth weights, respectively.

Key words: adiponectin, leptin, birth weights, venous blood, cord venous blood