The Effect of Dietary Sulphate Copper Supplementation on Growth Performance, Intestinal Digestive Enzymes and Absorptive Transporters in Weanling Pigs

The experiment was conducted to assess the effects of dietary supplementation of Cu on the growth performance, digestive enzymes, tissue minerals and absorptive transporters in small intestinal mucosa of weanling pigs. One hundred crossbred pigs weaned at 28 ± 2 d of age were assigned randomly to one of the following diets with 5 replicates: corn-soybean basal diet with 10, 100, 175, 250 mg/kg of Cu as CuSO₄•5H₂O. The results showed that 250 mg/kg Cu had a positive effect (P < 0.05) on average daily gain, daily feed intake and ratio of gain/feed. Compared to 10 mg/kg Cu, higher Cu had significant effect on the apparent digestibility of protein and fat (P < 0.05). The supplementing of Cu improved amylase and lipase activity in jejunum content and lipase in pancreas (P < 0.05) and had no effect on intestinal morphology. The liver Cu elevated approximately 4-fold in pigs fed diet with 250 mg/kg Cu compared with pigs fed diet with 10 mg/kg Cu, no increases were observed in pigs receiving the lower level of Cu (100 and 175 mg/kg). Both Fe and Zn contents in kidney and liver were not affected by Cu supplementation. There was no positive effect (P > 0.05) of Cu supplementation on PepT1 (peptide transporter 1) and SGLT1 (sodium/glucose cotransporter) mRNA abundance in intestinal mucosa. However, higher supplementing level (250 mg/kg) significantly elevated the DMT1 (divalent metal transporter) mRNA abundance in duodenum mucosa. These results suggested that dietary supplementation with 250 mg/kg Cu could improve growth performance, nutrient digestibility and intestinal enzyme activities of weanling pigs.