Breeding strategies to improve lamb survival and maternal efficiency in meat sheep

This research explores how reproductive performance data from adult ewes—such as lamb numbers born, reared, and lost by weaning—can enhance lamb survival and maternal efficiency in meat sheep. Non-genetic factors like feeding and management significantly influence these traits, which reflect maternal efficiency and flock profitability. A direct genetic component also affects lamb survival, particularly during in-utero development and early life. The SMARTER project identified novel genetic markers linked to lethal mutations in the Manech Tête-Rousse breed, including CCDC65 (respiratory distress), MMUT (metabolic failure), and SLC33A1 (embryonic loss), all contributing to pre-weaning mortality. Screening for these mutations can reduce lamb losses, though validation in other breeds is needed. Funded by the EU Horizon 2020 Programme (grant 772787).