Chinese team show potential of curcumin for E. coli control in pigs
Writing in International Immunopharmacology, the Chinese research team found dietary curcumin supplementation had a protective effect of that ingredient on intestinal mucosa barrier of enterotoxigenic E. coli (ETEC) challenged piglets.
But the authors, based at the Chinese Academy of Tropical Agricultural Sciences and Hainan University, said further study is needed to fully understand the molecular mechanism of the additive in that regard.
Weaning time is a critical stage in the management of piglets – it can cause diarrhea, digestive disorders and poor growth rate, as well as high morbidity and mortality in piglets.
“It has been demonstrated that weaning is associated with changes to the architecture of the small intestine, disturbed intestinal microbiota and diminished immune responses,” said the researchers.
And E. coli is a major cause of post-weaning diarrhea in piglet, they added.
To help piglets cope with weaning stress, antibiotics such as quinocetone, chlortetracycline, lincomycin and amoxicillin have been widely used as animal feed additives in China because of their effective growth-promoting activity and antimicrobial effects.
But due to growing antibiotic resistance in poultry there is growing interest in finding scientific, safe, effective and environment-friendly alternatives to those drugs, reported the researchers.
Antioxidant properties
Curcumin, a hydrophobic polyphenol, is a principal active compound of turmeric and extensive in vitro and in vivo studies have shown that it has a number of biological activities including antioxidant and anti-inflammatory effects, said the authors.
While the protective effects of curcumin on intestinal mucosa barrier have been repeatedly demonstrated in a variety of gastrointestinal disease models in rats and humans, knowledge about its impact on the intestinal mucosal barrier function of pigs is still scarce, said the team. Hence, the reason for this study, they added.
They investigated the effects of curcumin on growth performance and intestinal mucosal barrier function.
The study
Fifty piglets, weaned at around 21 days of age, were randomly allotted to five treatments for 21 days.
The dietary treatments were as follows: (1) basal control diet (A group); (2) basal diet + 50 mg/kg quinocetone (B group); (3) basal diet + 200 mg/kg curcumin (C group); (4) basal diet + 300 mg/kg curcumin (D group), and (5) basal diet + 400 mg/kg curcumin (E group).
The piglets were housed in individual pens and orally challenged with ETEC during the preliminary trial period.
The effects on intestinal mucosal barrier function, said the researchers, were assessed by analyzing jejunal morphology and histology, jejunal mucosal membrane integrity, secretory immunoglobulin (sIgA), Toll-like receptor 4 (TLR4) and cytokine expression.
Results
The results showed that, compared with the control, dietary addition of 300 mg/kg or 400 mg/kg curcumin decreased feed/gain ratio and crypt depth, improved villus height and villus height:crypt depth ratio, reduced plasma d-lactate and DAO activity, and up-regulated the protein expression of sIgA.
Research findings on effect of curcumin on growth performance of weaned piglets
Items | Treatments | SEM2 | P | ||||
|---|---|---|---|---|---|---|---|
A group | B group | C group | D group | E group | |||
Initial weight (kg) | 6.16 | 6.17 | 6.15 | 6.15 | 6.18 | 0.080 | 0.920 |
Final weight (kg) | 12.05 | 12.87 | 12.46 | 13.06 | 13.33 | 0.188 | 0.206 |
ADG (g/day) | 283.43 | 322.56 | 302.89 | 331.20 | 344.10 | 10.000 | 0.336 |
ADFI (g/day | 552.17 | 580.40 | 558.01 | 587.43 | 588.88 | 12.526 | 0.763 |
F/G | 1.95a | 1.77b | 1.85ab | 1.75b | 1.70b | 0.031 | 0.005 |
Those levels of curcumin supplementation also increased the number of goblet cells (GCs) and reduced the number of intraepithelial lymphocytes (IELs), said the team.
The mRNA levels of interleukin 1β and TLR4 and tumor necrosis factor α were also decreased, but mRNA level of interleukin 10 was increased, wrote the Chinese scientists.
Adding 50 mg/kg of quinocetone in the piglet diets also decreased feed/gain ratio, increased villus height: crypt depth ratio and reduced crypt depth and mRNA levels of TLR4, they said.
But the authors found in favor of curcumin on the immunity aspect.
“Curcumin and the quinocetone have similar effects in improving piglet growth, but dietary addition of 300 mg/kg or 400 mg/kg curcumin was more effective than quinocetone in improving intestinal mucosal barrier integrity, morphology, and immune status of weaned pigs,” they concluded.
Source: International Immunopharmacology
Published online ahead of print: doi:10.1016/j.intimp.2015.04.038
Title: Effects of curcumin on growth performance, jejunal mucosal membrane integrity, morphology and immune status in weaned piglets challenged with enterotoxigenic Escherichia coli
Authors: W. Xuna, L. Shia, H. Zhoua, G. Houa, T. Caoa, C. Zhaob
