ABSTRACT
The objective of the present study was to test the hypothesis of B. subtilis and B. licheniformis supplementation to a negative control diet in comparison to a standard control diet, had the potential to improve the performance and nutrient digestibility of growing-finishing pigs. For this purpose, 384 fattening pigs of 85 d of age were allotted to three treatments: a standard diet, a negative control (NC) diet (5% soybean meal replaced by 5% rapeseed meal), or a NC diet + probiotic. After reaching a body weight of approximately 110 kg, all animals going to the slaughterhouse (87% of total pigs) were selected to measure carcass quality. Moreover, the apparent total tract digestibility of protein was evaluated at the end of the grower period. The results of this study indicate that supplementation of the tested Bacillus-based probiotic significantly improved average daily gain (ADG, +14.6%) and Feed:gain ratio (F:G, -9.9%) during the grower phase compared to the NC diet. The improvement observed during the grower phase was maintained for the whole fattening period (ADG, +3.9%). Probiotic supplementation significantly improved the total apparent faecal digestibility of dry matter and crude protein in pigs at the end of the grower period. The improvements observed with the additive tested could indicate that supplementation of the Bacillus-based probiotic was able to counteract the lower level of crude protein and standardised ileal digestible amino acids in the NC diet by means of improved protein digestibility.
ABSTRACT
The effects of dietary probiotic supplementation with viable Bacillus subtilis and Bacillus amyloliquefaciens spores on sow performance, immunity, gut functional status and biofilm formation by probiotic bacteria in piglets at weaning were investigated. Ninety-six sows reared in a continuous farrowing system for one full cycle were fed gestation diets during the first 90 d of pregnancy and lactation diets until the end of lactation. The sows were fed a basal diet without probiotics (control; n = 48) or a diet supplemented with viable spores (1.1 × 109 CFU/kg of feed) (probiotic; n = 48). At 7 d of age, sucking piglets (n = 12/group) were provided prestarter creep feed until weaning at 28 d of age. The piglets in the probiotic group were supplemented with the same probiotic and dosage as their dams. Blood and colostrum collected from sows and ileal tissues collected from piglets on the day of weaning were used for analyses. Probiotics increased the weight of piglets (P = 0.077), improved the weaning weight (P = 0.039) and increased both the total creep feed consumption (P = 0.027) and litter gain (P = 0.011). Probiotics also improved the faecal score in the second (P = 0.013) week of life. The immunoglobulin G (IgG) concentrations in sow blood at farrowing and the IgM concentrations in piglet blood at weaning were higher in the probiotic group than in the control group (P = 0.046). The piglets from the probiotic-treated sows showed a higher IgM concentration in the ileal mucosa (P = 0.050) and a lower IgG concentration in the ileal mucosa (P = 0.021) compared with the piglets from control sows. The probiotic-treated piglets had a thicker ileal mucosa (P = 0.012) due to the presence of longer villi and larger Peyer's patches (P < 0.001). B. subtilis and B. amyloliquefaciens were detected in the probiotic-treated piglets but not the control piglets; these bacteria were present in the digesta and villus structures and formed structures resembling biofilms. Overall, Bacillus-based probiotic supplementation improves the health indices of sows and their piglets.
