Effects of dietary zinc oxide nanoparticles supplementation on growth performance, zinc status, intestinal morphology, microflora population, and immune response in weaned pigs.

Abstract

This study evaluated the effects of dietary zinc oxide nanoparticles (nano-ZnOs) on growth performance, zinc status, intestinal morphology, microflora population, and immune response in weaned piglets. A total of 150 weaned piglets (9.37 ± 0.48 kg) were randomly allotted to five dietary treatments and fed with a basal diet (control), or the basal diet supplemented with nano-ZnOs at 150, 300, or 450 mg kg-1 , and 3000 mg kg-1 ZnO for 21 days. After a feeding test, six pigs from the control, 450 mg kg-1 nano-ZnOs and 3000 mg kg-1 ZnO groups were slaughtered. Compared with the control, dietary supplements of nano-ZnOs and ZnO could improve (P < 0.05) average daily weight gain (ADG), average daily feed intake (ADFI), and villus height to crypt depth ratio in the duodenum and jejunum, and decrease (P < 0.05) diarrhea incidence. Zinc retention in the serum, heart, liver, spleen and kidney of pigs supplemented with nano-ZnOs and ZnO was increased (P < 0.05). Nano-ZnOs decreased (P < 0.05) the zinc excretion compared with conventional ZnO. Lower Escherichia coli counts in the cecum, colon, and rectum were observed (P < 0.05) in the nano-ZnOs group compared with the other groups. Compared with the control, ZnO and nano-ZnOs increased (P < 0.05) the serum concentration of IgA, IL-6, and TNF-α, and decreased (P < 0.05) the concentration of IgM. These results indicated that low doses of nano-ZnOs can have beneficial effects on growth performance, intestinal morphology and microflora, and immunity in weanling pigs, which are similar to the effects of pharmacological dosages of conventional ZnO. Nano-ZnOs may reduce mineral excretion, which may reduce environmental challenges. © 2018 Society of Chemical Industry.