The reproductive performance of Finnish Landrace × Dorset Horn and Border Leicester × Scottish Blackface ewes mated three times in 2 years

Abstract

SUMMARYThe reproductive performance of 51 Finnish Landrace × Dorset Horn (FD) ewes was compared with that of 50 Border Leicester × Scottish Blackface or Greyface (GF) ewes. Ewes were mated without hormone synchronization in November 1973 and with hormone synchronization in August 1974 and again in February 1975. Conception rates at the three matings were 88, 82 and 73% respectively in FD ewes and 96, 56 and 26% respectively in GF ewes. Mean litter size over three lambings was 2·34 in FD ewes and 2·15 in GF ewes. Stillbirths accounted for 12·0 and 10·2% of all lambs respectively and further lamb deaths during and after birth were 15·2 and 4·3% respectively; 11·6% of live FD lambs and 7·7% of GF lambs were fostered or reared artificially. The losses resulted in mean numbers of lambs weaned per ewe lambing of 1·75 from FD ewes and 1·85 from GF ewes (including lambs from those ewes that were artificially reared). Annual productivity was 2·13 and 1·67 lambs respectively.