JOURNAL OF ANIMAL AND VETERINARY ADVANCES, cilt.10, sa.18, ss.2402-2407, 2011 (SCI-Expanded)
This study was conducted to determine the anti-stress effect of the dietary humate and organic acid supplementation on laying hem when subjected to high stocking density as a social stress factor. A total of hundred, 40 weeks, brown laying hens were housed at two different stocking densities of 287.7 (high density) and 500 (low density) cm(2)/hen. For the control group, 16 hens were randomly assigned to 4 groups, 4 replicates of 4 birds each and were kept in low density. The control group received a basal diet. The remaining 84 hens were divided into 3 treatment groups, 4 replicates of 7 birds each and were housed at high density. The treatment group were fed either a basal diet (crowded control) or the basal diet supplemented with either 0.15 humate (Humate group) or 0.20% organic acid (organic acid group) of diet for 60 days. The results show that in hens kept in high density heterophils and Heterophil to Lymphocyte (H:L) ratios, an indicator of stress were raised while lymphocytes decreased. Humate supplementation resulted in significant in. creases in the lymphocyte counts and significant decreases in the heterophil counts and H:L ratios compared with those of the crowded control. The heterophils, lymphocytes and H:L ratio were not influenced by organic acid treatment. The present results suggest that humate supplementation to diet may be a favorable alternative for help poultry to cope with social stresses.