Repeatability of reproduction rate components in Merino and
Booroola x Merino ewes
R.P. Lewer, A.J. Allison
Invermay Agricultural Research Centre, Mosgiel
Proceedings of the New Zealand Society of Animal Production.
1980, 40: 248-253
Number of lambs born per ewe exposed to the ram and present at
lambing (NLB) was observed in Merino (M) and Booroola x Merino (BM) ewes
born in 1973 and 1974 up until lambing, 1978. Ovulation rate was
analysed for the crossbred ewes only. When 2-year performance was
classified on NLB performance, it was found that BM ewes in each
category outperformed equivalent M ewes at all later ages studied.
Repeatability estimates were calculated as the regression of later on
earlier record. The repeatability of NLB for BM ewes was 0.35 compared
with 0.20 for M ewes. Ovulation rate repeatability for BM ewes was
0.61.
Keywords: NZSAPAB;
Last Updated 12-09-1998
