The Effects Of Dietary Vanadium On Intestinal Immune Function And Antioxidant Function In Broilers

The purpose of this study was to investigate the effects of dietary excess vanadium on intestinal immune function and antioxidant function in broilers by the methods of biochemical reagent kids, ELISA, immunohistochemistry and flow cytometry. A total of420one-day-old avian broilers were divided into six groups. There were seven replicates of ten broilers each. The birds were fed on a corn-soybean base diet (vanadium0.073mg/kg). Birds in the experimental groups were fed with the base diet plus5mg/kg (Group I),15mg/kg (Group II),30mg/kg (Group III),45mg/kg (Group IV), or60mg/kg (Group V) vanadium supplied as ammonium metavanadate (NH4VO3). When compared with those of contol group, the body weight were significantly decreased in groups Ⅱ Ⅲ Ⅳ Ⅴ during the experiment, and the body weight in group Ⅰ was significantly high at14d,21d,28d,35d and42days. Moreover, the malondialdehyde (MDA) content was significantly higher in30,45and60mg/kg groups than in control group. In contrast, the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px), and ability to inhibit hydroxy radical, and glutathione hormone (GSH) contents were significantly decreased mainly in45and60mg/kg groups in comparison with those of control group. The contents of interleukin-2(IL-2), interleukin-6(IL-6), interleukin-10(IL-10), interferon gamma (IFN-y) and tumor necrosis factor-alpha (TNF-a) were significantly lower in the30mg/kg,45mg/kg and60mg/kg groups than those in control group. The population of IgA+cells in the cecal tonsil was significantly lower in the45mg/kg and60mg/kg groups than in control group. The percentages of CD3+, CD3+CD4+and CD3+CDs+ T-cells were markedly decreased in45and60mg/kg group from14to42days of age in the ileum and cecal tonsil, however the changes of CD4+/CD8+ratio were not significant. It was concluded that dietary vanadium in excess of30mg/kg significantly reduced the abovementioned antioxidase activities, cytokines contents and the population of IgA+cells in the cecal tonsil and the percentages of ileum and cecal tonsil T-cells subsets in the intestines of broilers, which could impact the antioxidant function and inteatinal immune function. The intestinal health was finally impaired in broilers.