Effect of probiotic inocula and/or nutribiotics on the population density of lactic acid bacteria in the intestine of weaning pigs

Summary

Food safety and health issues increased the need to use alternative procedures to antibiotics to combat pathogens in livestock. We evaluated the potential health-improving effects of both a probiotic and/or prebiotic feed formula in four series of trials. In a first and second experimental series, weaning pigs were fed respectively with different strains of Bifidobacterium spp. as probiotics and different fructo- and galacto-oligosaccharides as prebiotics. The best probiotic strains and prebiotic fiber resulting from these two series were jointly used in a third series. The composition of the cecal microbiota of the weaning pigs was analyzed and in vivo trials were conducted to evaluate the effects of the feed supplements. Bifidobacteria strains with a similar ability to develop in the hindgut had a different effect on the piglet performance depending on the dose in which they were provided. Our data also support that the presence of fructo-oligosaccharides can stimulate the occurrence of bifidobacteria in the cecum. We did however not observe an additional growth stimulus when they were supplemented with an increasing dose of bifidobacteria. In the fourth series of trials the best feed supplementation formula (1011 cfu of a Bifidobacterium animalis subps. lactis twice a day per pig) was challenged by infecting the pigs with a pathogenic strain of Salmonella.