Effect of dietary supplementation with inulin and/or benzoic acid on the incidence and severity of post-weaning diarrhoea in weaner pigs after experimental challenge with enterotoxigenic Escherichia coli

Abstract

The purpose of this study was to evaluate the effects of feeding pigs with inulin and/or benzoic acid on post-weaning diarrhoea (PWD), indices of fermentation in the gastrointestinal tract, and production in pigs experimentally infected with an enterotoxigenic strain of Escherichia coli (ETEC). Forty-eight entire male pigs (Large White×Landrace) aged 21 ± 3 days of age and weighing 4.97 ± 0.08 kg (mean ± SE) were used in a 2×2 factorial experiment, with the respective factors being inulin (0 versus 8%) and benzoic acid (0 vs. 0.5%). Feeding inulin-supplemented diets improved (p = 0.022) the faecal consistency (FC) and reduced (p = 0.001) the incidence of PWD; however, the use of benzoic acid had no effects on PWD or faecal ETEC shedding. Wet faeces (a higher FC score) were associated with increased faecal ETEC shedding (R² = 0.394, p = 0.001). Inulin reduced the total concentrations of short chain fatty acids (p = 0.029) in the proximal colon. The total concentration of lactic acid was increased by inulin in the caecum (p = 0.007) and proximal colon (p = 0.002). Feeding inulin or benzoic acid had no effects on production after weaning.

Keywords:

• pigs
• benzoic acid
• inulin
• post-weaning interval
• diarrhoea

Acknowledgements

This study was financially supported by an Australian Research Council-Linkage Grant, with Danish Pig Production, the Department of Agriculture and Food of Western Australia, and Wandalup Farms Ltd. as the industry partners. The technical assistance of Ms A. Hernandez, Ms J. Mansfield and Mr J. Heo is gratefully acknowledged.