Effect of rumen-protected methionine on production and composition of early lactating Shami goats milk and growth performance of their kids

Abstract

Abstract. This study was conducted at the Agricultural Research Station of the University of Jordan in the Jordan valley to evaluate the effect of supplementing rumen-protected methionine to early lactating Shami goats on milk production, composition, fatty acid profile, and growth performance of their kids. Twenty-four fresh lactating Shami goats were randomly assigned into three dietary treatment groups (eight each) in a completely randomized design. Diets were a control with no supplements or supplemented with either 2.5, or 5.0 g/head/d rumenprotected methionine. The experiment started exactly after kidding and lasted for 60 days thereafter. Production variables studied were milk production, milk composition, body weights, feed intake, kids weaning weight, and milk fatty acids. Daily milk production and energy corrected milk were not affected by protected me thionine supplementation. Milk Percentages of fat, protein, total solids, and casein were also not affected by protected methionine supplementation. Likewise, fat and protein yields were not different among dietary treatments of protected methionine. No differences in milk fatty acids composition were observed by supplementing rumen protected methionine in the experiment. Feed intake, feed to milk ratio, and final body weight of dams were not changed among treatments. No differences were observed in weaning weights, average daily gain, and milk to gain ratio of kids born to dams in the experiment regardless to sex of kids. In conclusion, results indicated that supplementing rumen protected methionine to dairy goats diet did not improve their milking performance, the composition of their milk, or growth performance of their kids.