Reproductive Performance of Western and Dorset X Western Ewes under a Fall-Lambing Program

Publisher Website
Google Scholar
Abstract
The lifetime reproductive performance of 120 purchased Western ewes (predominately Rambouillets) was compared with that of 120 raised Dorset × Western ewes when both ewe breed groups were managed for fall-lambing. Records were available over a 10-yr. period (1957 to 1966) as to the number of ewes lambing and the number of lambs born and reared by each ewe breed group. Fall-lambing dates were also available for the ewes of each breed group. Breeding for fall-lambing began on May 20 and continued for 40 days. A 30-day “cleanup” breeding period beginning on August 20 was also permitted. This breeding procedure resulted in fall (Oct. 15 to Nov. 25) and winter (Jan. 15 to Feb. 15) lambing. On the average, a higher percentage (7.7%, P<.10) of the Dorset × Western ewes lambed during the fall of each year, they had a higher lambing rate (0.19, P<.005), reared more lambs per 100 ewes (22.6, P<.01) in the flock and lambed about 3 days earlier (P<.01) than the Western ewes. On the average during the winter, a higher percentage (4.3%, N.S.) of the Western ewes lambed, they had a slightly higher lambing rate (0.03, N.S.) and reared more lambs per 100 ewes (6.7, N.S.).

This publication has 0 references indexed in Scilit: