Some Physiological studies on infertility in cattel with a special reference to insulin like growth factor 1

aim of the work - ) In order to clarify the role played by insulin-like growth factor I(IGF-I) in animal fertility, the study was carried out to study the relationship between IGF-I and puberty and resumption of postpartum ovarian cyclicity.The study was carried out in the Department of Physiology, Faculty of Veterinary Medicine, Zagazig University. After obtaining blood samples from heifers (n=20) and cows (n=20) reared in farms in Sharkia Governorate. These animals were divided into eight Blood samples were collected via jugular vein of these animals in the morning( at 10 a.m.) in tubes without anticoagulant. After that immediately blood was left sloped for 2 hours at room temperature and then centrifuged at 2500 rpm for 20 min for obtainiThe obtained results revealed the following:-I-Serum IGF-I level:-1-Relation between serum IGF-I level and Puberty:-The study revealed a significant decrease in serum IGF-I level in delayed pubertal heifers (130 18.23 ng/ml) as compared with normal pubertal heifers (301 51.82 ng/ml).