Dietary zinc glycine chelate on growth performance, tissue mineral concentrations, and serum enzyme activity in weanling piglets.

One hundred twenty crossbred piglets (Duroc x Landrace x Yorkshire) were used to determine the effects of dietary zinc glycine chelate on growth performance, tissue mineral concentrations, and serum enzyme activity. All pigs were allotted to four treatments and fed with basal diets supplemented with 0, 50, and 100 mg/kg Zn as zinc glycine chelate or 3,000 mg/kg Zn as zinc oxide (ZnO). After the 35-day feeding trial, results of the study showed that, compared to the control, average daily gain was improved (P < 0.05) for pigs fed 100 mg/kg Zn from zinc glycine chelate or 3,000 mg/kg Zn from ZnO and Zn concentrations in serum and M. longissimus dorsi were significantly enhanced by 100 mg/kg dietary zinc glycine chelate and 3,000 mg/kg ZnO. In addition, supplementation of 100 mg/kg zinc glycine chelate decreased (P < 0.05) the liver Fe level, liver Zn level, spleen Cu level, and kidney Cu level compared to that of the 3,000-mg/kg ZnO group. For feces mineral excretion, 3,000 mg/kg Zn from ZnO greatly increased the concentration of fecal Zn (P < 0.01) and Mn (P < 0.05) compared to that of the control or the 100-mg/kg zinc glycine chelate group. Moreover, alkaline phosphatase and Cu/Zn superoxide dismutase activities of pigs in 100 mg/kg zinc glycine chelate and ZnO treatments were greatly higher than that of the control. The results of present study showed that supplementation with zinc glycine chelate could improve growth and serum enzyme activities and could also decrease zinc excretion in feces in weanling pig compared to high dietary ZnO.