Black tea reduces diarrhoea prevalence but decreases growth performance in enterotoxigenic Escherichia coli-infected post-weaning piglets

• Published in: Journal of animal physiology and animal nutrition 2011-06, Vol.95 (3), p.388-398
• Main Authors: Bruins, M.J, Vente-Spreeuwenberg, M.A.M, Smits, C.H, Frenken, L.G.J
• Format: Article
• Language: English
• Subjects: animal; Animals; astringency; black tea; Camellia sinensis - chemistry; Cross-Over Studies; diarrhea; Diarrhea - drug therapy; Diarrhea - microbiology; Diarrhea - veterinary; diarrhoea; diet; disease models; enteric infections; Enterotoxigenic Escherichia coli; Escherichia coli Infections - drug therapy; Escherichia coli Infections - microbiology; Escherichia coli Infections - veterinary; feed conversion; feed intake; growth performance; humans; iron; palatability; piglets; Plant Extracts - chemistry; Plant Extracts - therapeutic use; polyphenols; Swine; Swine Diseases - drug therapy; Swine Diseases - microbiology; weaning; weight gain; Weight Gain - drug effects
• ISSN: 0931-2439; 1439-0396
• DOI: 10.1111/j.1439-0396.2010.01066.x

Enterotoxigenic Escherichia coli (ETEC) is a main cause of diarrhoea in humans and piglets. In vitro, black tea extract (BTE) has anti-pathogenic properties. Anti-diarrhoeal properties of BTE were assessed in a pig model of gastrointestinal infection. At weaning (day 0), piglets (n = 96) were randomly assigned to a diet containing 0% (control), 0.4% or 0.8% (wt/wt) BTE during 27 days. Piglets were orally infected with 6.4 × 10⁶ cfu of ETEC on day 6. Faecal consistency, feed intake and body weight were measured. In a sub-study (n = 30 piglets), the effect of BTE palatability on feed intake was assessed. Additionally, the effect of BTE on ETEC growth in the presence or absence of iron was studied in vitro. The 0.8% BTE diet reduced diarrhoea prevalence by 20% but also decreased feed intake by 16% and feed efficiency by 12% over the total period. The 0.4% BTE diet decreased feed efficiency and weight gain from day 13 onwards. The palatability study demonstrated that piglets preferred the control to the BTE diets. In vitro, BTE delayed ETEC exponential growth, which was reversed by iron addition. Although BTE had anti-diarrhoeal properties, this effect was accompanied by impaired performance. The absence of a correlation between diarrhoea prevalence and feed intake suggests that reduced diarrhoea directly results from BTE rather than from reduced feed intake caused by BTE astringency.