Response of feeding different levels of zinc and vitamin A on haematological and serum biochemical parameters in broiler chicken

An six week biological experiment was undertaken to evaluate the effect of feeding varying dietary levels of vitamin A and Zinc on various haematological and serum biochemical parameters in broiler chicken. The experiment was of 3×4 factorial design with three levels of Zinc (40, 60 and 80 mg/kg) each having four levels of vitamin A (1500, 3000, 6000 and 10, 000 IU/kg diet), resulting in to 12 dietary treatments, which were allocated a quadruplicate lot of 8 broiler chicken, thus accommodating 32 broiler chicks per treatments. At the end of feeding trial 2 ml blood sample was collected randomly from 8 birds per treatment in test tubes containing heparin as anticoagulant for study of haematological parameters. Same birds were also used to collect blood samples into sterile glass test tube without addition of anticoagulant for study of serum biochemical parameters. Results indicated that the various haematological parameters such as Hb%, TEC, TLC, ESR, PCV and DLC (lymphocyte, monocyte, heterophil, eosinophil and basophil) remained statistically nonsignificant due to different dietary treatments. However, significantly (P<0.05) higher serum ALP values were observed at dietary combinations of 60 mg Zn with 6000 IU/kg vitamin A followed by 60 mg Zn with 10, 000 IU/kg vitamin A and 80 mg Zn with 1500 IU/kg vitamin A than those recorded in other dietary combinations. Significantly (P<0.05) lower serum glucose contents were noticed in a dietary combination of 80 mg Zn with 3000 IU/kg vitamin A followed by 40 mg Zn with 6000 IU/kg vitamin A than those recorded in other dietary combinations. Significantly (P<0.01) higher ALP was recorded at 60 mg Zn/kg diet than those recorded at 40 and 80 mg Zn/kg diet. Significantly (P<0.01) lower serum phosphorus was observed at 40 mg Zn/kg diet than those recorded at 60 and 80 mg Zn/kg diet. Significantly higher values of serum ALP were observed at 6000 and 10, 000 IU/kg vitamin A than that observed at 3000 IU/kg vitamin A. The ALP observed at 1500 IU/kg vitamin A was found comparable with other dietary vitamin A levels. Based on the results it was concluded that a dietary combination of 40 mg Zn/kg with 6000 IU/kg vitamin A was found adequate for optimum haematological and blood biochemical parameters in broiler chickens.