Effect of serving capacity of the ram syndicate on flock fertility

Abstract

Serving capacity was measured in nine Merino rams during two pen-mating tests each of 2 hours duration. Two groups each of four rams were subsequently formed; a high serving capacity group (group H) of mean serving capacity 11.50 ± 0.50 (SEM) in two hours, and a low serving capacity group (group L) of mean serving capacity 3.50 ± 0.62. Each group was then mated to separate flocks of approximately 200 ewes each, for 6 weeks. Group H rams raddled significantly more ewes during the first 16 days of mating and inseminated a significantly greater proportion of the raddled ewes than did group L rams. Estimates of fertilization rates and embryo loss were similar for both groups. The proportion of ewes lambing as a result of the 6 weeks mating was similar in both groups (95.3% in group H and 93.5% in group L).