Genetic and environmental effects on fat content and quality in merino lambs

Aim of this study was to find genetic and environmental effects on fat cont ent and fat quality in lamb carcasses. 211 merino lambs were kept in four d ifferent performance groups and tested on fat content and quality (fat acid composition). Far content traits: like fat score, kidney fat, fat area (M. long. dorsi) and subcutaneous fat thickness are highly correlated among ea ch other as well as to daily gain. The correlation between fat area and dai ly gain was e. g. r(P) = 0.61 (p < 0.05). In this study no sire effect was found for the Fat content parameters. The one performance group kept under extensive cond itions showed less fat content than the intensively kept groups and male la mbs less than females. In the extensive group a higher portion of saturated fat acids was found. The results of the intensively kept group corresponds to the one kept under standardized conditions for official performance tes ting. For fat quality genetic variance components were found. The heritabil ity for the trait "portion of mono unsaturated fat acids" is 0.19 <plus/min us> 0.10. The ratio between linoleic and linolenic acid has no ram effect a nd no additiv genetic variance component.