Production and milk composition of sheep amaintained in tropical region

SUMMARY The aim of this study was to quantify the production and the chemical composition of the milk of ewes of Rabo Largo breed raised under two feeding systems during the lactation. Sixty ewes, primiparous and multiparous, aged one to four, years nursing one or two lambs were raised under two feeding systems, with average body weight of 43 kg and 40.5 kg for the groups supplemented and not supplemented, respectively. The milk yield were measured weekly, using the indirect method of double weighing, after a period of colostrum. Milk samples were also collected every week for determination of the chemical composition. The data of daily milk production were analyzed with repeated measures over time and across groups of factors. The subject factors considered were year and rainy and dry periods in early lactation, lactation order, interaction between type of lambing and sex of the offspring and between the batches. For comparison of means between batches, we used the average of the least squares with a significance level of 5%. It was found that the supplemented group presented a higher milk yield than the not supplemented group, except to the two last weeks old lactation. Already peak production occurred during the second week of lactation for both lots. The dietary supplementation increases the production and maintained the highest levels of the chemical components of milk in the last week of lactation.