Abstract This study evaluated the effects of different combinations of inorganic (I) and organic (O) zinc (Zn; ZnO or Zn proteinate) and copper (Cu; CuSO4 or Cu-amino acid complex) sources on their intestinal and liver ATP concentrations and antioxidant response in weaned piglets. At weaning (d21; 7.79 ± 0.49 kg), one hundred piglets were randomly allocated to 5 dietary treatments consisting of different combinations of inorganic and organic Zn and Cu at 300 and 130 mg/kg, respectively (IZnICu, OZnOCu, IZnOCu, OZnICu) and an additional treatment with high levels of inorganic Zn and Cu (HZnHCu; 3000 and 250 mg/kg, respectively). Tissues samples were collected at d28 and 35. The antioxidant response was evaluated in plasma, jejunal mucosa and liver whereas ATP concentrations were analyzed in jejunum mucosa and liver. Statistical analysis compared the different combinations of Zn and Cu versus the high level of these trace minerals in addition to a 2x2 factorial contrast between the different combinations of Zn and Cu at each time point. No effect was detected on plasma SOD and GPX activity or carbonyl protein concentrations (P ≥ 0.15). There was no effect on jejunum SOD activity, carbonyl protein and ATP concentrations (P ≥ 0.12). For jejunal GPX, activity was lower for HZnHCu than the others groups at d35 (P = 0.05) but no difference was detected between the combinations of sources (P = 0.31). In liver, SOD activity tended to be higher for OZn than IZn groups (P = 0.10) and was higher for OCu than ICu groups (P = 0.05) at d28. At d35, SOD activity was lower for HZnHCu than the others groups (P 0.01) and higher for OZn than IZn groups (P = 0.01). The hepatic activity of GPX was lower for HZnHCu than the others groups at d28 and 35 (P 0.01) but no difference was observed between the combinations of sources (P = 0.20). Hepatic carbonyl protein concentrations at d28 tended to be lower for HZnHCu than the others groups (P = 0.10) and tended to be higher for OCu than ICu groups (P = 0.10). The hepatic concentrations of ATP at d28 were lower in HZnHCu than the others groups (P = 0.04) and tended to be higher for OZn than IZn groups (P = 0.10). In conclusion, HZnHCu supplementation had detrimental effects on the hepatic antioxidant response. Regardless of the combination of sources, the most notable effects were observed in the liver after OZn and OCu supplementation.
Dalto et al. (Wed,) studied this question.