Increase in Ovulation Rate in Sheep Following Administration of an LHRH Analogue

A nonapeptide (D-Ser (TBU)6-EA10; Hoe 766; Hoechst AG), 25 times more potent than LHRH in LH and FSH releasing activity, was administered (2 µg s.c. in 0.5 percent gelatin) to ewes on Day 1 (n=51), Day 12.5 (n=48) or Day 14.5 (n=39) of the estrous cycle (Day 0 = day of estrus). A control group (n=23) was not treated. Ovulation rate at the estrus or time of expected estrus following treatment was increased (P<0.05) in ewes injected on Day 12.5 (1.36) compared to ewes in the control group (1.09) and ewes injected on Day 1 (1.13), but not in ewes (0.05