Dietary Zinc Oxide Modulates Antioxidant Capacity, Small Intestine Development, and Jejunal Gene Expression in Weaned Piglets

Abstract

The current study was conducted to investigate the effects of dietary zinc oxide (ZnO) on the antioxidant capacity, small intestine development, and jejunal gene expression in weaned piglets. Ninety-six 21-day-old piglets were randomly assigned to three dietary treatments. Each treatment had eight replicates with four piglets per replicate. The piglets were fed either control diet (control) or control diet supplemented with in-feed antibiotics (300 mg/kg chlortetracycline and 60 mg/kg colistin sulfate) or pharmacological doses of ZnO (3000 mg/kg). The experiment lasted 4 weeks. Blood samples were collected at days 14 and 28, while intestinal samples were harvested at day 28 of the experiment. Dietary high doses of ZnO supplementation significantly increased the body weight (BW) at day 14 and average daily gain (ADG) of days 1 to 14 in weaned piglets, when compared to control group (P < 0.05). The incidence of diarrhea of piglets fed ZnO-supplemented diets, at either days 1 to 14, days 14 to 28, or the overall experimental period, was significantly decreased in comparison with those in other groups (P < 0.05). Supplementation with ZnO increased the villus height of the duodenum and ileum in weaned piglets and decreased the crypt depth of the duodenum, when compared to the other groups (P < 0.05). Dietary ZnO supplementation decreased the malondialdehyde (MDA) concentration at either day 14 or day 28, but increased total superoxide dismutase (T-SOD) at day 14, when compared to that in the control (P < 0.05). ZnO supplementation upregulated the messenger RNA (mRNA) expression of zonula occludens-1 (ZO-1) and occludin in the jejunum mucosa of weaned piglets, compared to those in the control (P < 0.05). The pro-inflammatory cytokine interleukin-lβ (IL-1β) mRNA expression in the jejunum mucosa was downregulated in the ZnO-supplemented group, compared with the control (P < 0.05). Both in-feed antibiotics and ZnO supplementation decreased the mRNA expression of interferon-γ (IFN-γ), but increased the mRNA expression of transforming growth factor-β (TGF-β), in the jejunum mucosa of piglets, when compared to those in the control (P < 0.05). In summary, supplemental ZnO was effective on the prevention of post-weaning diarrhea (PWD) in weaned piglets and showed comparative growth-promoting effect on in-feed antibiotics, probably by the mechanism of improvement of the antioxidant capacity, restoration of intestinal barrier function and development, and modulation of immune functions.

Dietary High Zinc Oxide Modulates the Microbiome of Ileum and Colon in Weaned Piglets

“…A previous study has identified a positive correlation between swine weight and the abundance of the family Spirochaetaceae (Unno et al, 2015). Similarly, the increased proportion of Spirochaetaceae by dietary high ZnO supplementation observed in this study may be linked to our early observation that dietary high ZnO improved BW of weaned piglets (Zhu et al, 2017). Furthermore, the percentages of Verrucomicrobia were significant higher in ZnO group or antibiotics group in the ileum.…”

“…A total of ninety-six crossbred barrows (Duroc × Landrace × Large White) weaned at 21-day-old, with an initial body weight (BW) of 5.99 ± 0.04 kg, were used in this study, as described in our recent study (Zhu et al, 2017). Briefly, piglets were randomly allotted to three dietary treatment groups: (1) control group (piglets were fed basal diet without any in-feed antibiotics); (2) antibiotic group (piglets were fed the basal diet with in-feed antibiotics of 300 mg/kg chlortetracycline and 60 mg/kg colistin sulfate); and (3) ZnO group (piglets were fed the basal diet with 3,000 mg/kg ZnO).…”

“…However, in-feed antibiotics have been strictly regulated in the application of modern livestock industry due to the increase of antibiotic resistance and its potential contaminations to human (Barton, 2000; Bach Knudsen, 2001; Smith et al, 2002). Instead, dietary supplements with zinc oxide (ZnO) will be more promising because it contributes to better growth performance (Broom et al, 2006; Namkung et al, 2006; Zhu et al, 2017), enhancement of intestinal morphology and function, improvement in antioxidant capacity as well as restorations of the mucosal barrier integrity in weaned piglets (Sargeant et al, 2010; Zhu et al, 2017). The underlying mechanism of high ZnO on the regulation of intestinal health in weaned piglets may have an impact on the gut microbiome.…”

The injury of serotonin on intestinal epithelium cell renewal of weaned diarrhoea mice

“…29-31 For instance, a decrease of diarrhoea incidence was accompanied by an increase in villus height of the duodenum and ileum and a decrease in crypt depth of the duodenum in weaned piglets with ZnO-supplemented diets. 30 Changes in VH and CD are considered key measurements for the assessment of gut maturation and nutritional effects. 32 There are many published papers on the crosstalk of diarrhoea and intestine.…”

Studying the Differences of Bacterial Metabolome and Microbiome in the Colon between Landrace and Meihua Piglets

“…Piglets at 65 days of age were weighed again and the average daily weight gain of piglets within each breed was calculated. At the end of the experiment, all piglets were slaughtered for sample collections as previously described (Zhu et al, 2017 ). Fresh ileum and colon mucosa, and colon contents were collected and shock-frozen in liquid nitrogen, then stored at −80°C until analysis.…”