Evaluation of replacing inorganic zinc with organic zinc on growth performance, immune system, antioxidant status, morphology of jejunum, and tissue zinc retention in broilers

This study was contacted to evaluate the effects of replacement of inorganic zinc with organic zinc on the growth performance, immune system, antioxidant status, morphology of jejunum, and tissue zinc retention in broilers. The number of 150 Ross 308 broilers were used in a completely randomized design with Duncan's test at the statistical signification level of 0.05, in 3 treatments and 5 replicates and 10 birds in each replicate. The treatments wear: 1) basal diet based on corn and soybean without zinc 2) basal diet + 22 mg/kg organic zinc + 88 mg/kg zinc sulfate 3) basal diet + 33 mg/kg organic zinc + 77 mg/kg zinc sulfate. At day 42 of the experiment, one bird from each replicate was sacrificed and used for analysis. The results showed that replacement of inorganic zinc with organic zinc had no significant effect on the growth, feed intake, and feed conversion ratio of broilers. Also, it did not have any significant effect on the amounts of immunoglobulins (IgG, IgM and IgA). However, the antioxidant evaluation showed that the usage of organic zinc can respectively increase and decrease the amounts of superoxide dismutase and Malondialdehyde in the liver. Besides, morphological evaluation of intestine indicated that the organic zinc improved the villi height and width. In general, it seems that the usage of organic minerals, such as zinc, in the diet of boilers improves their immune system and antioxidant status.