Ultrasound characterization of ovarian activity in ewes and does under egyptian conditions

This work aimed to study the influence of season on ovarian activity in cyclic ewes and does in Egypt. Nondescript ewes (n=82) and does (n=58) of 2 to 6 years age were investigated ultrasonographically per rectum from December 2018 to December 2019. Ovarian structures were evaluated for mean follicle number (MFN), mean growing follicle diameter, maximum follicle diameter (Max-FD), mean number and diameter of large pre-ovulatory follicles, follicle deviation (FD) and corpus luteum diameter (CLD). The overall frequency of ewes and does exhibiting follicular and luteal phases were 84.29% (n=118) and 15.71% (n=22), respectively. Season significantly influenced the ovarian activity in terms of MFN (p<0.02), Max-FD (p<0.003), in ewes and FD (p<0.04) in does. In conclusion, ultrasound monitoring of ovarian activity in the cyclic ewes and does showed that season affected follicular growth and maturation especially in ewes, and follicle dominance in does under the local Egyptian conditions.