Impact of weaning and an antioxidant blend on intestinal barrier function and antioxidant status in pigs

Abstract

The objective of this experiment was to investigate the influence of weaning stress and an antioxidant blend on gut health and free radical metabolism in postweaning pigs. A total of 96 pigs from 12 litters were randomly divided by litter to 3 groups with 4 litters each. The control group and the weaning group were fed the basal diet, and the antioxidant group was fed the basal diet supplemented with an antioxidant blend. The control group was suckling normally during the experimental period and the other 2 treatments were weaned at 21 d of age. Morphology in different parts of the intestines was used as a measure of intestinal barrier function. Activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and the concentrations of malondialdehyde (MDA), NO, H(2)O(2), and O(2) were measured in serum. Activities of the digestive enzymes, including sucrase, maltase, amylase, lipase, and pepsin, were measured at 24 d of age for all treatments. Gene expressions of free radicals, digestive enzymes, or antioxidant enzymes were selected for quantitative reverse transcription-PCR analyses. Results showed that weaning resulted in reductions (P< 0.05) in the villus height and width, and activity of digestive enzymes. Activity of SOD decreased (P < 0.05) and the concentrations of MDA, NO, and H(2)O(2) increased (P < 0.05) after weaning. The expression results indicated that the genes related to the antioxidant enzymes and digestive enzymes were down regulated (P < 0.05) after weaning. Tumor protein 53, which regulates reactive oxygen-species generation, tended to increase (P < 0.10) in the weaning group. The concentration of PPARγ coactivator-1α (PGC-1α), which plays an important protective role against oxidative stress by regulating the expression of mitochondrial antioxidants, was reduced (P < 0.05) in weaning pigs and increased (P < 0.01) in antioxidant pigs compared with the control pigs. Results indicated that intestinal dysfunction occurred after weaning and there was an inhibition of the antioxidant system. The antioxidant blend has the potential to prevent free radical-induced damage and suppress oxidative stress by modulating the expressions of tumor protein 53 and PGC-1α genes.

A carvacrol–thymol blend decreased intestinal oxidative stress and influenced selected microbes without changing the messenger RNA levels of tight junction proteins in jejunal mucosa of weaning piglets

“…Recent studies have indicated that early weaning may induce intestinal oxidative stress, which contributes to intestinal dysfunction (Wang et al, 2008;Zhu et al, 2012). In this study, we have investigated whether supplementing a carvacrol-thymol blend in the diet lowered early All results are presented as mean ± SEM (n = 6).…”

“…Numerous studies have shown that dysfunction of the intestine, which has important immunological, metabolic and barrier functions, has been demonstrated to play a crucial role in weaning-induced growth check (Wijtten et al, 2011;Campbell et al, 2013). Recent studies have indicated that decreased antioxidant activity and increased production of reactive oxygen species (ROS) is involved in weaning-induced intestinal dysfunction, resulting in intestinal oxidative stress (Wang et al, 2008;Degroote et al, 2012;Zhu et al, 2012). The intestinal oxidative stress is frequently associated with inflammation (Rada et al, 2011;Padgett et al, 2013).…”

Effects of dietary supplementation with freshwater microalgae on growth performance, nutrient digestibility and gut health in weaned piglets

“…Cyanobacteria Spirulina platensis and freshwater microalga Chlorella vulgaris are frequently referenced in human nutrition for their physicochemical properties with a potential benefit on gut health, such as antioxidant, anti-inflammatory and antimicrobial activities (Kitada et al, 2009;Hoseini et al, 2013). In pigs, Spirulina and Chlorella could help maintaining digestive function after weaning by limiting intestinal damage caused by immune and inflammatory responses to dietary transition and oxidative stress Zhu et al, 2012). Dietary supplementation with Spirulina and Chlorella has been considered for their nutritional value (Lipstein and Hurwitz, 1980;Yap et al, 1982), but few studies considered Spirulina and Chlorella as functional ingredients (Janczyk et al, 2009).…”

“…Compared with control pigs, the total tract energy digestibility was greater in pigs receiving diets supplemented with Spirulina or Chlorella and the digestibility tended to be greater for DM, organic matter and NDF. The dietary transition at weaning involves an intestinal release of free radicals responsible for oxidative stress (Zhu et al, 2012) Furbeyre, van Milgen, Mener, Gloaguen and Labussière and an increased expression of pro-inflammatory cytokines . These cytokines are supposed to be responsible for the alteration in mucosal structure (Pluske et al, 1997), with a drastic decrease in villus height and brush border enzyme activities during the first 5 days after weaning (Pluske et al, 1997;Lallès et al, 2004), reducing nutrient absorption and growth performance .…”

“…A greater villus height in the jejunum of pigs receiving diets supplemented with Spirulina and Chlorella could result from a reduction in mucosal damage caused by oxidative stress (Zhu et al, 2012) or local inflammation after weaning, and explain the increased nutrient digestibility in trial 2. However, the beneficial effect of Spirulina supplementation on intestinal morphology and function seems to be observed only in healthy piglets without diarrhoea.…”