Relationship between the responsiveness to multiple-ovulation treatment and the number of bovine oocytes collected by transvaginal follicle aspiration

To characterize factors affecting the number of bovine oocytes recovered tr ansvaginally, a regression analysis was performed between the responsivenes s to multiple-ovulation treatment and the number of oocytes recovered trans vaginally. The number of embryos recovered following multiple-ovulation tre atment and the number of oocytes recovered transvaginally increased when th e number of follicles to be aspirated transvaginally increased (P<0.05, P<0 .01). The number of cumulus-oocyte complexes recovered transvaginally also increased when the number of oocytes to be aspirated transvaginally increas ed (P<0.001). However, the number of viable embryos that recovered followin g multiple-ovulation treatment had no relation to the number of cumulus-ooc yte complexes recovered transvaginally. These results suggested that more o ocytes can be recovered from donors that have a high responsiveness to mult iple-ovulation treatment.