Comparison of porous and nano zinc oxide for replacing high-dose dietary regular zinc oxide in weaning piglets

Abstract

The aim of this study was to compare the effect of dietary supplementation with low dose of porous and nano zinc oxide (ZnO) on weaning piglets, and to evaluate the possibility of using them as an alternative to high dose of regular ZnO. Piglets were randomly allocated into four treatment groups fed with four diets: (1) basal diet (NC), (2) NC+ 3000 mg/kg ZnO (PC), (3) NC + 500 mg/kg porous ZnO (HiZ) and (4) NC + 500 mg/kg nano ZnO (ZNP). The result showed that piglets in HiZ group had less diarrhea than ZNP group (P < 0.05). Besides, there was no significant difference between PC, HiZ and ZNP groups in terms of serum malondialdeyhde (MDA) concentration and glutathione peroxidase (GSH-Px) activity (P > 0.05). Analysis of trace metal elements revealed that piglets fed with high dose of regular ZnO had the highest Zn level in kidney (P < 0.05), which may induce kidney stone formation. Additionally, a decrease in ileal crypt depth was observed in PC, HiZ and ZNP group, suggesting an effective protection against intestinal injury. Results of mRNA analysis in intestine showed that ZNP supplementation had better effects on up-regulated trefoil factor 3 (TFF3) and nuclear factor erythroid 2-related factor 2 (Nrf2) levels in duodenum and jejunum than HiZ did (P < 0.05), implying that nano ZnO may possess higher anti-inflammatory capacity than porous ZnO. In conclusion, dietary supplementation with low dose of porous and nano ZnO had similar (even better) effect on improving growth performance and intestinal morphology, reducing diarrhea and intestinal inflammatory as high dose of regular ZnO in weaning piglets. Compared with nano ZnO, porous ZnO had better performance on reducing diarrhea but less effect on up-regulation of intestinal TFF3 and Nrf2.

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

“…Impaired intestinal epithelial function disrupts immune homeostasis and increases inflammation, disturbing the intestinal barrier function, unbalancing absorptive‐secretory electrolytes, and leading to fluid and diarrhea . Our results indicated that 450 mg kg −1 nano‐ZnOs and 3000 mg kg −1 ZnO protected small intestinal morphology by increasing the villus height, which was consistent with the results reported by Long et al ., who reported that the supplemental nano‐ZnOs of 500 mg kg −1 protected against intestinal injury. Enterohemorrhagic E. coli (EHEC) is an enteric pathogen that leads to diarrhea mediated by intestinal epithelial barrier disruptions during the weaning phase .…”

“…The inconsistent results could be attributed to the different concentrations and sources of nano‐ZnOs. However, analysis of the incidence of diarrhea showed that adding 450 mg Zn kg −1 diet as nano‐ZnOs was as efficacious as 3000 mg Zn kg −1 diet from ZnO, which is closely akin to the conclusion that a low dose (500 mg kg −1 ) of nano‐ZnOs had a better effect in improving growth performance and alleviating diarrhea as reported by Long et al . From the results of a feeding test we found that the growth performance of pigs given 300 and 450 mg kg −1 nano‐ZnO was very similar, while the diarrhea rate in pigs given 450 mg kg −1 nano‐ZnO was lower than that in 300 mg kg −1 .…”

“…Much unused ZnO was excreted with the feces, which affected total mineral absorption (antagonistic action) and excretion, and caused a remarkable deterioration in the environment . Feeding with 2500 mg kg −1 ZnO increases the proportion of multi‐resistant Escherichia coli in ileum and colon digesta, which causes diarrhea . The European Commission has voted to phase out ZnO as a veterinary instrument in the entire European Union within 5 years.…”

“…Nanosized ZnO as dietary supplementation increased Zn digestibility, serum Zn concentration, carbonic anhydrase activity, and growth hormone concentration compared to regular‐sized Zn . Nano‐ZnOs improve intestinal microbiota and inflammation response, and have a similar effect as a high dose of regular ZnO on improving intestinal morphology and inflammation in weaning piglets . Zinc oxide nanoparticles have been applied to reduce the total amount of ZnO added to the diets because of environmental challenges and poor absorption of ZnO.…”

The effects of dietary supplementation with porous zinc oxide on growth performance, intestinal microbiota, morphology, and permeability in weaned piglets

“…In the current study, dietary supplementation with 500 mg/kg HiZox or 3,000 mg/kg ZnO increased the villus height at the jejunum and ileum, and the VC at the duodenum, jejunum, and the ileum, while decreased crypt depth at the duodenum and jejunum. Previous findings reported that supplementation of 500 mg/kg HiZox decreases the crypt depth of the duodenum and jejunum in growing piglets (Long, Chen, et al, ; Long, Xu, et al, ). Dietary supplementation with 500 mg/kg MMT‐ZnO increased the villus height and the VC of the jejunal mucosa in weaned piglets (Hu et al, ).…”