Mating behavior of ram on ewes at induced estrus during the non-breeding season.

FUKUI Yutaka, TSUBAKI Minoru, KOBAYASHI Masayuki, ONO Hitoshi

doi:10.1262/jrd1977.32.195

Mating behavior of four Suffolk rams and its effect on fertility in 47 hormonally-treated ewes during the non-breeding season were investigated. Each ram was allowed to mate 11 or 12 ewes in a 5 × 8 m breedig pen (single-sire mating). The observation was continuous for 48 hs after hormonal treatment and joining of rams. The items of observa-tion were numbers of mounts and services per ewe, ratio of mounts/services per ram, intervals and distribution order of services in each ram. Mating behavior varied markedly between rams. The mean numbers of mounts and services per ewe were 12.6 and 3.3, 35.7 and 6.6, 8.4 and 1.8, and 36.0 and 2.5 for the four rams (A, B, C, and D, respectively). The ratio of mounts/services (14.6) in the youngest ram (D) was significantly (P< 0.01) higher than the ratio of the other three rams. The distribution order of services to estrous ewes by each ram was also variable. Ram mating preference was observed, especially in the youngest ram. However, these differences in ram mating behavior did not relate to detection of estrous ewes. Although the proportions of lambed ewes against the number of marked ewes were not significantly different among the rams used, it was revealed that there was a significant difference (P< 0.05) in lambing rates between rams A and D. Maiden ewes had lower (P< 0.025) lambing rate (27.8%) than parous ewes (71.4%). It was considered from the present results that mating behavior of rams and status of ewes (maiden or parous) could be the important factors affecting on fertility during the non-breeding season.

Mating behavior of ram on ewes at induced estrus during the non-breeding season.

Bibliographic Information

Description

Journal

Citations (2)*help

Details 詳細情報について

Export

Report a problem