Effect of genotype, sex and litter size on growth and basic traits of carcass quality of light lambs

Abstract

Evaluation of the effect of genotype (Romanov breed: n = 26, and F1 crossbreds of Suffolk-Romanov: n = 29), sex (males: n = 37 and females: n = 18) and litter size (singles: n = 6, twins: n = 16, triples: n = 21 and quadruplets: n = 12) on growth and basic carcass quality traits of light lambs was carried out at an organic sheep farm in Kuklík over the years 2007 and 2008. Throughout the experiment the lambs were reared with their mothers, indoors. The weaning of lambs was carried out just before slaughter. The daily feeding ration of the lambs consisted of the mother’s milk (ad libitum) and organic mineral lick (ad libitum), whereas the lambs had free access to the feedstuff of their mothers.The daily feeding ration of the ewes consisted of haylage (2.5 kg/ewe), meadow hay (ad libitum) and organic mineral lick (ad libitum). The genotype (G) and the sex (S) had not a significant effect on growth of lambs in the period from birth till the slaughter. On the other hand the litter size (LS) had a highly significant effect on this trait, whilst the highest daily gain in above-mentioned period was found in singles (157 g). Concerning the carcass traits the G had a significant effect only on carcass dressing percentage while the S had a significant effect only on proportion of kidney. Nevertheless the LS had a significant effect on carcass dressing percentage and the proportions of skin, kidney and kidney fat. In conclusion it can be completed that the fatness scores of all individual carcasses were relatively very low which is important for good realisation of the carcasses on the market.

Keywords

• lamb
• Romanov
• Suffolk
• growth
• carcass quality