893
Genetic Parameters and Trends for Hogget Live weight, Wrinkle score and Scrotal traits in Merino Lines Divergently Selected for the Ability of Ewes to rear Multiples
Data were recorded for hogget live weight (LW), wrinkle score (WS), testis diameter (TD) and scrotal circumference (SC) of a resource population divergently selected from the same base since 1986, either for (H line) or against (L line) maternal multiple rearing ability. Estimates of heritability were 0.45 for LW, 0.52 for WS, 0.29 for TD and 0.30 for SC. Genetic correlation of LW with WS was moderate and negative. Genetic correlations of LW with scrotal measurements were high and positive at ≥ 0.55. Genetic trends in the H line indicated significant change in all traits. H line animals became heavier and plainer with larger testes. Genetic trend for testicular measurements was reduced by the inclusion of live weight as a covariate. No conclusive evidence of genetic change was found in L Line, except for a marked increase in WS.
Keywords:
Live weight
wrinkle score
scrotal circumference
testes diameter
