Precaecal and faecal digestibility of inulin (DP 10-12) or an inulin/Enterococcus faecium mix and effects on nutrient digestibility and microbial gut flora

The aim of the present study was to investigate the precaecal and faecal digestibility of inulin (DP 10-12) and inulin/Enterococcus faecium mix, and the effects of these substances on nutrient digestibility and microbial gut flora. For the experiment four of eight male pigs were fitted with an end-to-end ileo-rectal anastomosis (IRA) with preserved ileo-caeco-colic valve. The residual pigs were used as intact partner (IN). The animals received 1.5 kg/day of a diet based on corn, wheat, barley and soybean meal, supplemented with either 8 x 10(9) CFU E. faecium/kg, 2% inulin or a mixture of both substances. The digestibility trial was carried out from weeks 4 to 8 after surgery. Precaecal digestibility of inulin was assessed to be 57%. The addition of E. faecium to the diet resulted in a similar precaecal digestibility of inulin of 55%. Supplementation of E. faecium, inulin, and a mixture of E. faecium and inulin did not affect precaecal and faecal nutrient digestibility with the exception of the precaecal digestibility of CF which increased when inulin alone was supplemented. Bacterial population in the digesta of IRA and IN pigs were not affected by the experimental diets except the concentration of bifidobacteria and lactobacilli. The supplementation of E. faecium to the diet significantly decreased the concentration of bifidobacteria and the population of lactobacilli inclined to decrease when IN pigs received the probiotic diet. The combination of E. faecium and inulin prevented a reduction of enterococci in faeces of IN pigs. The daily digesta excretion (DM) tended to decrease in IRA and IN pigs when inulin was supplemented. The results indicate that inulin (DP 10-12) in pig nutrition did partly react as a prebiotic as has been confirmed for humans. A combination of E. faecium and inulin improves the survival of the probiotic strain through the upper intestinal tract and allocates the synbiotic effect. Furthermore inulin might be able to show positive effects on precaecal and faecal microbial characteristics.