Animal growth, tissular composition, and carcass conformation of light Merino lambs

Neither the age (average 74.3 ± 2.9 days) nor the arrival weight of males and females (average 15.38 ± 0.25 kg) at the fattening farm, after the lactation period, were statistically significant. At the end of the fattening period, statistically significant differences were found for the weights and growth of the two sexes (25.91 ± 0.59 kg vs. 22.52 ± 0.52 kg (p-value: 0.000), and 242.15 ± 10.15 g/day vs. 178.51 ± 9.86 g/day (p-value: 0.006) in males and females respectively). Regarding carcass conformation measurements, the differences between sexes were statistically significant for: K, G and Th, but not F. In the carcass performance, there were significant differences between males (7.5 ± 0.3) vs. females (6.7 ± 0.2) (p-value: 0.023), which means that the males had a rating of R- and the females O+. Regarding tissue composition, only the percentage of muscle was significantly higher in males (58.50 ± 0.88) than in females (52.94 ± 0.76), (p-value: 0.011). After the logical differences between males and females, the study showed that both sexes had a higher growth potential than the final weights at which the study was carried out, since they did not show a high fattening (22.76 ± 0.86 percentage). Our results were in accordance with other authors.This research has been financed by a collaboration agreement between the Agricultural Technological Institute of Castilla and León (ITA- CYL), the University of Valladolid (UVa) and the Scientific Park Foundation of the UVa and the project AGL2016-75159-C2-1-R funded by the Spanish State Research Agency (AEI) and the European Regional Development FundLight lambGrowthCarcassMerino breedUnpublishe