Effects of coated nano zinc oxide on growth performance, immune function, and intestinal barrier of weaned piglets.

The study was conducted to compare the effects of different forms of nano-zinc oxide on the growth performance, immune function, and intestinal barrier of weaned piglets. A total of 192 weaned piglets aged 24 days (half in male and female), with an average weight of (7.47 ± 0.62) kg were randomly divided into four groups, with six replicates in each group and eight piglets in each replicate. The control group was fed a basal diet, and the experimental group I, group II and group III were fed with 2 000 mg/kg nano-zinc oxide, 500 mg/kg coated nano-zinc oxide, 1 000 mg/kg coated nano-zinc oxide, respectively. The experiment lasted for 14 days. The results showed that the total effective rate of nano zinc oxide was 7.12%, which was lower than that of coated nano zinc oxide (78.54%). All forms of nano zinc oxide significantly increased the final weight and average daily gain of weaned piglets (P<0.05), and significantly decreased the ratio of feed to gain and diarrhea rate (P<0.05), with the best effects observed in the experiment group III. Compared with the control group, the levels of immunoglobulin M and immunoglobulin A in the serum of weaned piglets in all experimental groups were significantly increased (P<0.05), and the secretion of immunoglobulin in the cecum and colon was significantly elevated in the experiment group I and experiment group III (P<0.05). Different forms of nano zinc oxide significantly decreased the serum diamine oxidase activity and endotoxin content in weaned piglets (P<0.05). The study indicates that dietary supplementation of nano zinc oxide and coated nano zinc oxide of weaned piglets can promote growth, reduce diarrhea rate, enhance immune function, and improve intestinal barrier function. The effects of 1 000 mg/kg of coated nano zinc oxide are better. [ABSTRACT FROM AUTHOR]