Feed efficiency for meat and wool production by Merino and F1 Dohne×Merino lambs fed pelleted diets of different nutritive value

Abstract

There is anecdotal evidence from Western Australian breeders that Dohne sheep maintain a higher level of meat and wool production than Australian Merinos. Feed efficiency, carcass and wool attributes are moderately heritable so we hypothesised there would be differences in these traits between Merino and F1 Dohne × Merino lambs. Two groups of 15 Merino and 15 F1 Dohne × Merino wether lambs (29–40 kg) were fed a pelleted diet of either moderate or high energy and protein content for 48 days. Ad libitum pellet intake and liveweight gain were measured and the feed conversion ratio (FCR) for both wool growth and liveweight were calculated. Wool growth and quality were measured and the lambs were slaughtered to measure carcass and meat quality attributes. The F1 Dohne lambs were heavier at the start of the study and grew faster than the Merinos (P < 0.05) irrespective of diet. Consequently, the carcasses of the F1 Dohne lambs were heavier than the Merinos (P < 0.001), but the differences in FCR were not significant. Merino lambs produced more clean wool of lower fibre diameter from less feed than the F1 Dohne lambs (P < 0.05). These results suggest that F1 Dohne × Merino lambs may have an economic advantage in terms of meat production, but this is traded-off against wool production.