Alternate two- and three-follicle wave interovulatory intervals in Holstein heifers monitored for two consecutive estrous cycles

Abstract

Follicle dynamics were monitored by ultrasonography for two consecutive estrous cycles in 11 Holstein heifers. Overall, 12 of the 22 cycles (55%) had three follicle waves and 10 (45%) had two follicle waves. Two heifers (18%) had consecutive two-wave cycles, three (27%) had consecutive three-wave cycles and six (55%) alternated between two- and three-wave cycles. These data demonstrate that the number of follicle waves can change from one estrous cycle to the next in Holstein heifers.