Hormonal stimulation and follicular development in prepuberal Mediterranean Italian buffaloes (Bubalus bubalis): ultrasound monitoring.

The aim of this study was to evaluate the utility of ultrasound monitoring in peripuberal buffalo heifers undergone three superovulatory treatments. Buffalo heifers (n=23) undergone ultrasound examination and received a progesterone releasing intravaginal device (PRID). After 3 days, Group A (n=7) received a 4-day decreasing dosage of an equal mixture of 500 I.U. of Follicle Stimulating Hormone (FSH and LH); Group B (n=7) was treated with a single administration of 2000 I.U. of Pregnant mare serum gonadotrophin (PMSG) and Group C (n=6) received the single injection of PMSG as Group B and a 2-day decreasing dosage of an equal mixture of 175 I.U. of FSH and LH starting on day 5. On day 0, 3, 5, 6 and 7 all buffaloes undergone ultrasound examination and number and size of the follicles was recorded. A high number of medium and large follicles were obtained from all buffaloes. Group C resulted in a significantly higher number of large–very large follicles, compared to group A and B. It is possible to hypothise that the further injection of FSH stimulated the recruitment and the growth of other small follicles. The ovarian ultrasound monitoring of ovarian follicular development has been a valid tool to evaluate the efficacy of the treatments