Effects of betaine and sulfate supplementation on milk and wool production of Naeini ewes

Twenty lactating Naeini coarse wool ewes (45 ± 3.2 kg BW, approximately 35 months of age), were studied in a completely randomized design during a three-month experimental period in order to investigate the effect of betaine and sulfate supplementation on milk and wool characteristics. Treatments included, betaine supplementation, sulfate supplementation and betaine plus sulfate supplementation, along with control group. Ewes were randomly distributed in individual pens with five replications for each treatment. Isonitrogenous and isocaloric diets were twice offered to the ewes on a daily basis according to the NRC recommendation. The level of betaine used on the TMR was 5 g kg−1 betaine, and basal diet contained 0.17% DM organic sulfur. Dry matter intake (DMI) was altered by betaine and sulfate supplementation (P < 0.05). No significant effect of betaine and sulfate supplement was detected on body weight (P > 0.05). Milk yield and milk fat percentage were increased by betaine and sulfate supplementation (P < 0.05), whereas percentages of milk protein, lactose, ash and SNF were not significant by supplements (P > 0.05). Betaine and sulfate supplementation significantly increased the daily growth rate of the wool, and the wool yield was compared with that of the control group (P < 0.01). Mean fiber diameter was not affected by betaine and sulfate supplementation (P > 0.05). Staple length was affected by the type of supplements (P < 0.001). For the staple strength, a higher value was observed in the betaine plus sulfate treatment (P < 0.05). Betaine plus sulfate supplementation significantly increased the concentration of wool sulfur (P < 0.01). In contrast, wool wax and wool yellowness significantly decreased by the betaine and sulfate supplementation (P < 0.05). Although there was an increase in the plasma cysteine concentration, it was not a significant one (P > 0.05). In addition, no effects of betaine and sulfate supplementation were observed on plasma copper concentration. In conclusion, these data indicated that betaine plus sulfate supplementation had positive effects on milk and wool production of Naeini ewes.