The seasonality of reproductive performance of Merino sheep in Britain

Abstract

SUMMARYA study has been carried out to determine the length of the breeding season and the feasibility of lambing twice a year in Merino sheep in Britain.Six groups of 18 ewes were exposed to rams at monthly intervals, and twice per year, from April 1969 to June 1970. A well-defined breeding season, from August to January, was found, and its shortness, linked with the inability of the ewes to conceive immediately post partum, prevented lambing twice in the year.