Effects of Hot-Melt Extruded Nano-Copper as an Alternative for the Pharmacological Dose of Copper Sulfate in Weanling Pigs

This study was conducted to investigate the effects of hot-melt extrusion (HME)-processed copper (Cu) sulfate supplementation on the growth performance, gut microbiota, metabolic function of Cu, and bioavailability of Cu in weanling pigs fed a corn-soybean meal basal diets. A total of 180 piglets (Yorkshire x Landrace x Duroc) of mixed-sex randomly were allotted to six treatments on the basis of initial average body weight (6.36 +/- 0.39 kg) to six dietary treatments. There were six replicates in each treatment with 5 pigs per replicates. The dietary treatments included levels of CuSO4(IN6, 6 mg Cu/kg diets; IN125, 125 mg Cu/kg diets), nano-CuSO4(HME6, 6 mg Cu/kg diets; HME65, 65 mg Cu/kg diets; and HME125, 125 mg Cu/kg diets), and Cu-methionine (ORG125, 125 mg Cu/kg diets). The weanling pigs fed diets supplemented with the HME65 and HME125 showed a greater body weight and feed intake compared with IN6 and IN125 (P < 0.05). The weaning pigs fed diets supplemented with the HME125 showed the highest digestibility of gross energy in phase 1 and phase 2 (P < 0.05). The supplementation of HME125 significantly reduced the Escherichia coli (E.coli)in cecum and colon (P < 0.05). The supplementation of HME65 showed statistically equivalent effect on reduction ofE. coliin the cecum and colon compared with IN125 and ORG125 treatments. The villus height in duodenum and jejunum of piglets in HME65 and HME125 treatments were higher than ORG125, HME6, IN6, and IN125 (P < 0.05). The gene expression ofAtox1was upregulated in IN125, HME125, and ORG125 treatments (P < 0.05). The expression ofSod1was increased in IN125 treatment compared with IN6 treatment (P < 0.05). The HME125 treatment had the highest gene expression of ghrelin (P < 0.05). The Cu concentration of serum and liver was higher in the HME125 treatment than the HME6, IN6, and IN125 treatments (P < 0.05). The HME125 and ORG125 treatments showed a lower fecal Cu compared with IN125 treatment (P < 0.05). Taken together, these results suggest that the HME65 can be an alternative to IN125 in weanling pigs due to the greater overall average daily gain, improved villus height, and higher bioavailability.

Automated summary

This study investigated the effects of hot-melt extrusion-processed copper supplementation on weanling pigs, showing that HME65 significantly improved growth performance and had the highest digestibility rate.