The aim of this experiment was to evaluate the effect of different vitamin D metabolites on immune response and intestine morphometry of broiler chickens. We used 952 1-day-old chicks, male Cobb, distributed into a completely randomized design with four treatments, seven replications and 34 birds each. There were evaluated four different metabolites of vitamin D: D3, 25(OH)D3, 1,25(OH)2D3 and 1α(OH)D3, providing 2000 and 1600 IU/kg feed of vitamin D in initial and growth period, respectively. The different metabolites of vitamin D did not affect the relative weight of the organs except for the weight of the intestine and liver at 21 and 42 days. There was a significant effect (P<0.05) of the different metabolites of D3 vitamin on the villi length of jejunum and ileum at 7 days, between animals fed with 1,25(OH)2D3 and 1α(OH)D3 to the jejunum and 1,25(OH)2D3 and vitamin D3 to the ileum (P<0.05). There were no differences (P>0.05) for weight of lymphoid organs, cutaneous basophil hypersensitivity reaction, macrophage activity assessment, measurement of nitric oxide and heterophil profile: lymphocyte. The different sources of vitamin D affect the intestine morphometrics on the villi length in the initial phase, but the effect was not observed in other phases. The immunological parameters were not affected by metabolites of vitamin D.
Vitamin D3; cholecalciferol; macrophages; intestine; broilers