*4.2.6 Anti–prolactin*

Summer anestrus in buffaloes could be due to hyperprolactinemia, with this assumption bromocriptine, an anti-prolactin drug [25], has been used. Melatonin is also known to suppress prolactin secretion [26]; however, melatonin has been reported as stimulator of both GnRH and gonadotrophin secretions in buffaloes. As the plasma concentration of melatonin is low during summer, induction of estrus and ovulation by using melatonin implants have been reported by Ghuman et al. [27] in all treated summer anestrus buffalo heifers; however, the time taken to induce estrus and ovulation was highly variable (4–36 days).
