Ovarian Follicular Dynamics during the Estrous Cycle in Jennies in Upper Egypt

The objective of the current study was to describe follicular dynamics in Egyptian Jennies throughout the estrous cycle. In this experiment, 8 estrus cycles in 8 cyclic Jennies were studied from February to June using ultrasonography. The result revealed that one follicular wave per cycle was recorded throughout the studied period. Dominant follicle (DF) was firstly detected at -0.80 ± 0.84 day in Jennies. The growth rate of DF was 2.32 ± 0.18 mm/day. Left ovulations were nonsignificantly (P = .07) more than right ovulations (55.6% versus 44.6%). The CL was firstly detected at D 2.58 ± 1.2, developed in a rate of 1.19 ± 0.07 mm/day, reached a maximum diameter of 30.77 ± 1.28 mm at D 13.0 ± 0.70, and started to regress on D 17.05 ± 0.64 with a mean regression rate of 1.75 ± 0.17 mm d(-1). Results of the present study indicated that Jennies had one follicular wave per cycle. The Day of the cycle has a significant effect on the number of different classes of the ovarian follicles, but not large ones. Ultrasonographic characteristics of the preovulatory follicles could be useful to predict ovulation. CL developed and regressed in a slow rate.