Effect of Low Protein Diets Supplemented with Glycine on Growth Performance Carcass Traits, Blood Parameters and Antioxidant Status of Mandarah Chicks During Starter and Grower Periods

The objective of this study was to evaluate the effect of low protein diet fortified with 0.2% glycine (gly) on Mandarah a native Egyptian strain chick’s growth performance, carcass, small intestinal morphology, shank and keel bone length, blood parameters, growth hormone and blood antioxidant status during starter and growing periods (from 1 day to 12 weeks of age). A total number of 135 one day old Mandarah chicks were randomly divided into 3 equal groups with 3 equal replicates each. Control group (C) was fed normal crude protein diets (19% CP as starter and 17% CP for grower), group 2 (LP1) and 3 (LP2) fed 1.5 and 3% less crude protein respectively, than control supplemented with 0.2% glycine. Results indicated that LP1diet supplementation with glycine led to significant improvement in body weight (BW) during the starter period, and in feed conversion ratio (FCR) during the first 4 weeks of age. However, LP2+gly group recorded the lowest BW at 12 weeks of age, while recorded significantly better relative weights of carcass, liver, gizzard and spleen. Results also showed no significant differences in shank and keel length, goblet cell number, villi height, crypt depth, blood total antioxidant capacity, glutathione and all blood biochemical parameters. Glycine supplemented groups recorded significantly higher growth hormone values and lower litter moisture and litter nitrogen values. In conclusion adding glycine 0.2% to low protein diet (1.5% reduction) improve growth performance and litter quality of Mandarah local Egyptian strain during starter and grower periods.