Effect of Different Levels of Cadmium and Selinium on 1- Performance of Broiler Chickens

A total number of 540, one day old of commercial broiler chicks were used to study the effect of selenium (Se) and cadmium (Cd) separately and in mixture on broiler chicks' performance (from one day to 49 days of age). Birds were distributed randomly into 18 dietary treatments groups, each groups represented by triplicate pens (10 chicks each) until the end of the experiment (49 days of age). The 16 treatments were divided into 4 major groups. First group was used as a control (T1,T7 and T13) and fed the starter and finisher basal diet. The second treatment group was fed the basal diet supplemented with 0.5, 1.0, 1.5, 2.0 and 2.5 mg Se as a sodium selenite (Na2SeO3) /kg of the starter diet and 2.0, 4.0, 6.0, 8.0 and 10.0 mg Se as a sodium selenite (Na2SeO3)/kg of the finisher diet,( T2, T3, T4, T5 and T6), respectively. The third treatment group was fed the basal diet supplemented with 0.25, 0.5, 0.75, 1.0 and 1.25 mg Cd as a cadmium chloride (CdCl2) /kg of the starter diet and 1.0, 2.0, 3.0, 4.0and 5.0 mg Cd as a cadmium chloride (CdCl2) /kg of the finisher diet, (T8, T9, T10, T11 and T12), respectively. The fourth group was fed the starter and the finisher basal diet supplemented with mixture of the different levels of Se and Cd as previously mentioned in the second and the third groups (T14, T15, T16, T17 and T18). Average BW, BWG, FI and FCR decreased linearly with increasing of Se levels through the experimental periods. Moreover, the average BWG, FI and FCR among each of experimental periods showed quadratic responses with increasing of Se supplementation. Supplementation different levels of Cd to broiler diets during whole the experimental periods indicated that the average BW showed linear decrease and quadratic response while their BWG showed quadratic response during starter period wks with increased Cd levels. All the growth performance showed quadratic response from 5-7 wks, while only the average BWG showed the same response from 0-7 wks of age with increased mixture supplementation. No A.A. El-Deek, et al. 700 significant differences observed in the average livability among groups supplemented with Se, Cd and Se and Cd mixture levels.