This study was carried out to assess the effects of dietary supplementation of yeast-based Zn, Se, and Cr on growth performance, carcass characteristics, immune response, and histomorphological changes in broiler chickens. A total of 1092 one-day-old unsexed broilers of Ross 308 strain were randomly allocated into two equal treatment groups (6 equal replicates/ group). Birds were fed the dietary treatments from day 1 to day 35 of age. The first group was fed a basal diet without yeast-based Zn, Se and Cr supplementation (control). The second group was fed a basal diet supplemented with 1.5 mg, 0.15 mg and 2 µg / kg diet of Zn, Se, and Cr, respectively. The yeast-based Zn, Se and Cr increased (P<0.05) the growth rate, carcass traits and improved feed conversion ratio compared to control. The antibody titer against avian influenza and the relative weight of bursa, thymus and spleen were increased (P < 0.05) in broilers supplemented with yeast-based Zn, Se, and Cr compared with the control. The intestinal villi height and crypt depth and bursa diameters were increased in broilers fed the yeast-based Zn, Se and Cr supplemented diet. In addition, there was an increase in the lymphocytic infiltration in the bursa and a decrease in germinal centers in the submucosal lymph nodules of the ileum of birds supplemented with yeast-based Zn, Se and Cr compared to the control. In conclusion, dietary supplementation of yeast-based Se, Cr, and Zn in combination could improve growth performance, carcass traits, immune responses and histo-morphological parameters in broiler chickens.

Objective: This study was conducted to compare between the nanoparticles of copper (Cu-NP) and copper sulfate (CuSO4) effect on immunity, pro-inflammatory cytokine, oxidant/antioxidant balance, different behavioral patterns, growth rate, and weight gain by adding them in drinking water of broilers. Materials and Methods: One hundred and fifty broiler chicks of 1-day-old were randomly divided into three groups: the first group was the control, the second group received CuSO4 in drinking water (10 mg/l), and the third group received Cu-NP in drinking water (10 mg/l) with replicates (n = 25) for 5 weeks of age. Blood samples collected for estimating immunoglobulins (A, G, and M), superoxide dismutase, pro-inflammatory (IL-6), erythrocyte sedimentation rate, heterophil/ lymphocyte (H/L) ratio, malondialdehyde (MDA), corticosterone hormone, and lymphoid organs index weight. Moreover, behavioral observations were undertaken from the 2nd week until the 5th week of age for measuring different behavioral patterns (feeding, drinking, crouching, body care, and comfort behaviors). Chicks were individually weighed weekly (gm); also, the weight gain, the intake of food, and the ratio of feed conversion were calculated. Results: Cu-NP administration has improved the blood profile, lymphoid organs index weight in Cu-NP treated broilers in relation to control and CuSO4 treated groups. Conversely, erythrocyte sedimentation rate, H/L ratio, MDA, and corticosterone hormone were reduced by Cu-NP treat¬ment. Moreover, Cu-NP has a positive effect on all behavioral patterns more than other groups which significantly reflect on the weight of the body, gaining of weight, and the intake of food in the Cu-NP treated group of birds. Conclusion: The findings in this study stated that when the drinking water of broilers was supple¬mented with Cu-NP, there might be an improvement in the immunity, behavior, and productive performance more efficiently than CuSO4. [J Adv Vet Anim Res 2020; 7(1.000): 16-25]