Bovines suffer from inherent problems like late maturity, poor expression of estrus, irregular estrous cycle, seasonality in breeding, anestrous, low conception rate, long postpartum interval and repeat breeding which are the major constraints in livestock productivity and fertility. The different phases of reproductive cycle are regulated by intricate sequential events and interactions between hypothalamic releasing hormones, hormones secreted from the pituitary and sex steroids secreted by the ovary. Lack of integration or synchronization or endocrine imbalances at any phase of the sequence...