Effect of source of betaine on growth performance and carcass traits in lambs

An experiment was conducted to determine the effect of the source of betaine and sex on growth performance and carcass characteristics of growing lambs. A factorial structure 3×2 with dietary betaine and sex as main effects were made. A total of 60 Manchego breed lambs with an initial weight of 13 kg were randomly distributed into 12 pens. Weaned males and females were fed on a starter diet until 20 kg live weight (LW) and then were changed to a finisher diets up to the slaughter live weight (approx. 28 kg). Within each feeding period, starter and finisher diets containing 0 or 2 g kg−1 betaine (betaine anhydrous or rumen escape betaine) were used to fed each group of male and female lambs. Effect of sex was observed on daily gain, feed conversion rate, fat thickness (FT), and carcass characteristics (p<0.001); faster growth and less lipids deposition were found in males versus females. No effect of source of betaine was found on growth performance and carcass traits in male lambs. Female takes 12 more days than males to reach the slaughter live weight and more lipid depositions was observed. Reduction in fat thickness, perirenal fat and intramuscular content of lipids were found in female lambs when they were fed the diet enriched in betaine anhydrous (p<0.05). Same effect for diet with rumen escape added betaine and control were observed in male and female lambs.