Abstract
A higher proportion of ewes lambed to the first service (P < 0.01) when put to the ram at the second heat after treatment with MAP (123/162, 75.9%) than when mated at the first heat after treatment (89/158, 56.3%). A 60 mg daily dosage of MAP resulted in 13% more ewes lambing to the first service than did a 50 mg dosage rate (73.1% versus 59.8%, P > 0.05). There was no significant difference in fertility subsequent to MAP treatment for 12 versus 14 days.