Effects of -glucan and mannan-oligosaccharide supplementation on growth performance, fecal bacterial population, and immune responses of weaned pigs

Abstract

The effects of -glucan and mannan-oligosaccharide (BG + MOS) supplementation in feed on growth performance, bacterial population in feces and immune responses of weaned pigs were investigated. Two hundred and eighty-eight weaning piglets were randomly allocated into 3 groups with 8 replicates per group and 12 pigs per replicate. Group 1, as control, was fed a commercial basal nursery diet. Groups 2 and 3 were fed the same diet supplemented with BG + MOS (Biolex® MB-40) 1 and 2 kg/ton of feed, respectively. Weight gain (WG), average daily gain (ADG), average daily feed intake (ADFI) and feed conversion ratio (FCR) were calculated on days 1, 21 and 42 of experiment. Blood samples were analyzed for interleukin (IL)-1, IL-6 and tumor necrosis factor alpha (TNF-). Total bacteria, total coliform, Lactobacillus concentrations and Lactobacillus to Coliform ratio (L:C) in feces were also determined. Results showed that groups 2 and 3 had better WG, ADFI and ADG on days 1-21. No significant difference in growth performance was, however, observed among the groups on days 21-42 and 1-42. FCR was not different among the groups throughout the experiment. Both BG + MOS supplemented groups had reduction in total bacteria and coliform concentration in feces but increase in number of Lactobacillus spp. and L:C ratio. Similar extent of reduction in diarrhea incidence of both BG + MOS supplemented groups was observed during the first 3 weeks of experiment. Group 3 pigs exhibited higher PRRS antibody response than the others on day 42. No statistically significant difference in serum IL-1, IL-6 and TNF- among the groups was shown during the experiment. In conclusion, BG + MOS supplementation is potentially beneficial to growth performance on days 1-21, bacterial population balance in feces and diarrhea incidence reduction of weaning pigs.