SUMMARY

Twenty-eight (12 male and 16 female) of improved Jezersko-solèava lambs with Romanov (JSR) were used to evaluate the effect of live weight and sex on carcass traits and meat quality. Lambs were weaned at around 60 days of age. They were fed with commercial concentrate and hay ad libitum and slaughtered at 29 kg or 43 kg of average live weight at 105 or 126 days of age. Daily gain from birth to slaughter was higher than 300 g/day and was very similar for both groups. There were no differences between light and heavy lambs in carcass conformation and dressing percentage. Heavy lambs were longer, wider and fatter. The difference in lungs, head and pelt percentage were statistically significant. With increased live weight at slaughter the percentage of neck, back and rib with flank increased and chuck, shoulder and hindleg decreased. Muscle percentage in hindleg increased and bone percentage decreased as live weight increased. Considering meat quality, heavier lambs had lower lightness and higher redness. Lighter lambs had higher pH45 value. Differences between sexes were statistically significant for dressing percentage and carcass fatness with higher values for females. Males had higher percentage of liver and head, higher proportion of neck, chuck and shoulder and lower proportion of back and loin. Males tended to have higher values for muscle and bone proportion, and lower proportion of fat in hindleg. Males had lighter meat. Sex had no effect on pH values