Growth, carcass and meat quality in Zwartbles lambs slaughtered at different live weights

The aim of the study was to evaluate the effect of different live weights at slaughter (LWS) of Zwartbles lambs on their daily gain (DG), carcass traits (CT) and chemical and physical characteristics of the quadriceps femoris muscle (QFM). A total of four weight groups of lambs were evaluated: group A, LWS = up to 35 kg; group B, LWS from 35.1 to 40 kg; group C, LWS from 40.1 to 45 kg and group D, LWS from 45.1 to 50 kg. The LWS had a significant (P < 0.05) effect on DG and most CTs, when average DG and most weights of individual CTs increased with increasing LWS. The evaluation of the influence of LWS on the chemical and physical characteristics of QFM primarily shows that this factor had a significant (P < 0.05) effect only on the content of intramuscular fat (IMF) and redness index (RI), when in both cases the values of these traits increased (IMF: from 0.57 to 1.21%; RI: from 8.53 to 9.76) with increasing LWS. In conclusion, it can be stated that most of the monitored traits in all weight groups of Zwartbles lambs were comparable with their levels in specialized meat breeds of sheep