Reduction of subclinical Salmonella infection in fattening pigs after dietary supplementation with a ß-galactomannan oligosaccharide

Abstract

Aims: To assess the efficacy of a β-galactomannan oligosaccharide (ß-GMOS) for the control of Salmonella infection in fattening pigs.

Methods and results: Three different doses (0.5, 3 and 2 kg ß-GMOS per ton of feed) were used during the entire period of growing in three similar and independent field trials carried out in a small fattening unit (≈ 100 pigs). Treatment was randomly assigned to half of the pens. Individual serum samples (20-25 per group) were collected at different times during the fattening period and a similar number of faecal samples during the fattening period and at slaughter. In addition, mesenteric lymph nodes were collected at slaughter. Herdcheck(®) Swine Salmonella ELISA was used for serological analyses, the ISO 6579:2002/Amd 1 : 2007 for bacteriology and the PFGE for molecular characterization of Salmonella strains. The addition of ≥ 2 kg t(-1) of ß-GMOS to the pig diet during the entire fattening period was associated with a reduction in Salmonella prevalence, shedding and seroconversion.

Conclusions: Feed supplementation with ß-GMOS may be a useful complementary tool for the control of salmonellosis in fattening pigs.

Significance and impact of the study: ß-GMOS may be a complementary way of reducing Salmonella shedding and infection in fattening pigs.

Keywords: Salmonella; control; food safety; mannan oligosaccharides; pigs; pulsed-field gel electrophoresis.