The objective of this study was to evaluate the effects of dam breed on lambs sired by Charollais rams and purebred Charollais lambs obtained via embryo transfer. Frozen Charollais semen and embryos, used to obtain crossbreed and purebred Charollais lambs, were imported from elite flock with pedigrees and progeny test in Canada.The study was conducted on the crossbred Charollais lambs born from Tushin, and Romanov F1 ewes (Romanov × Morkaraman), and Charollais lambs born from Awassi, Morkaraman and Tushin surrogate ewes. The data was collected on 61 lambs (23 Charollais: CH, 20 Tushin × Charollais: F1 CH and 18 Charollais × Romanov F1:COR) from birth to weaning. Average weights at birth for CH, F1 CH and COR lambs were 4.32 ± 0.18 kg, 4.17 ± 0.18 kg, 3.18 ± 0.19 kg and at the age of 60 days were 21.20 ± 1.07 kg, 20.94 ± 0.84 kg, 18.13 ± 0.91 kg, respectively. The genotype of dams significantly affected birth and weaning weights of crossbred lambs, but not average daily live weight gain (ADG). Litter size had constant significant effect on the traits evaluated. Survival rates of crossbred lambs from birth to weaning were affected by the dam genotype. Birth weights and survival rates of CH lambs born from embryo transfer were affected by recipient genotypes and Awassi ewes were found to be the best surrogate mothers.

The objective of this study was to evaluate the effects of dam breed on lambs sired by Charollais rams and purebred Charollais lambs obtained via embryo transfer. Frozen Charollais semen and embryos, used to obtain crossbreed and purebred Charollais lambs, were imported from elite flock with pedigrees and progeny test in Canada.The study was conducted on the crossbred Charollais lambs born from Tushin, and Romanov F1 ewes (Romanov × Morkaraman), and Charollais lambs born from Awassi, Morkaraman and Tushin surrogate ewes. The data was collected on 61 lambs (23 Charollais: CH, 20 Tushin × Charollais: F1 CH and 18 Charollais × Romanov F1:COR) from birth to weaning. Average weights at birth for CH, F1 CH and COR lambs were 4.32 ± 0.18 kg, 4.17 ± 0.18 kg, 3.18 ± 0.19 kg and at the age of 60 days were 21.20 ± 1.07 kg, 20.94 ± 0.84 kg, 18.13 ± 0.91 kg, respectively. The genotype of dams significantly affected birth and weaning weights of crossbred lambs, but not average daily live weight gain (ADG). Litter size had constant significant effect on the traits evaluated. Survival rates of crossbred lambs from birth to weaning were affected by the dam genotype. Birth weights and survival rates of CH lambs born from embryo transfer were affected by recipient genotypes and Awassi ewes were found to be the best surrogate mothers.