The effect of betaine supplementation on the meat production performance of F₁ hybrid lambs from Dorper × Hu sheep crosses

The aim of this experiment was to investigate the effects of coated betaine (CBet) on fattening performance, blood physiological and biochemical indices, slaughter performance, and meat quality of F₁ hybrid lambs from Dorper × Hu sheep crosses. Eighteen healthy male weaning lambs of the F₁ generation with similar body weights (21.58 ± 0.60 kg) were randomly divided into two groups with nine lambs per group. The control group was fed a basal diet, and the experimental group was fed a basal diet supplemented with 0.20% coated betaine (CBet) (based on air drying). The test lasted for 70 days, including 10 days of the pre-test and 60 days of the trial. Growth performance was measured on days 0, 30, and 60 of the experimental period. After the experimental period, six animals were randomly selected to determine their slaughter performance and meat quality. The results showed that the compared with the control group 60-day average daily gain of lambs increased by 6.90% (P > 0.05) and the ratio of feed to meat decreased by 16.48% (P > 0.05). Compared to that of the control group, the erythrocyte-specific volume and hemoglobin concentration of lambs in the experimental group were significantly increased by 25.17% and 23.59% (P < 0.05), respectively, the white blood cell count was increased by 26.0% (P > 0.05), the cooked meat rate was significantly increased by 10.27% (P < 0.05), and the muscle shear force was decreased by 12.67% (P > 0.05). Compared to that of the control group, the contents of essential, sweet, and umami amino acids in the muscles of the experimental group were increased (P > 0.05), and the cystine content (Cys) was significantly increased by 50.00% (P < 0.05). Threonine (Thr), histidine (His), and tyrosine (Tyr) were increased by 11.53%, 15.79%, and 16.00%, respectively (P > 0.05). In addition, muscle fiber diameter and area decreased by 26.27% and 37.60% (P < 0.05), respectively, while muscle fiber density increased by 28.57% (P > 0.05). In conclusion, CBet can improve the 60-day average daily weight gain of weaned male lambs, improve muscle tissue morphology, increase the content of some amino acids in muscle tissue, and increase the concentration of red blood cells and hemoglobin in the blood, indicating that CBet can be used to improve the immune function of Dorper × Hu sheep crosses hybrid male lambs, thereby improving short-term fattening performance, meat quality, and economic benefits.