Ovarian follicular development during the estrous cycle in gilts following electrocautery of fillicles.

This experiment was designed .to study follicular development at various days of the estrous cycle in intact gilts for comparison with follicular growth following the removal of surface follicles from the ovaries by electrocautery at different stages of the estrous cycle. Thirty-five Yorkshire-Poland China gilts were divided equally into seven subgroups. Four of the subgroups served as controls and were slaughtered on day-2, -8, -14 o r 2 0 of the estrous cycle (day-0 = first day of estrus), respectively, and three of the subgroups were subjected to follicle-cautery on day-2,-8 or -14 of the estrous cycle, respectively, and were slaughtered 6 days after surgery. The following cyclical variations in follicular development were found in the intact control gilts: (1) the weight of the ovarian fluid increased (P<.05) to day-8, decreased (P<.05) to day-14 and then increased (P<.05) to day-20; (2) the number of small follicles (1 to 2 mm dia.) did not differ significantly among day-2, -8 and -14, but was reduced (P<.01) at day-20; (3) the number of medium follicles (3 to 6 mm dia.) and the total