175 Effects of Bacillus spp. probiotics on growth performance, diarrhea, and systemic immunity of weaned pigs experimentally infected with an enterotoxigenic Escherichia coli.

Abstract

The experiment was conducted to investigate the effects of Bacillus spp. on growth performance, diarrhea, and systemic immunity of weaned pigs experimentally infected with an enterotoxigenic Escherichia coli (E. coli). Weaned pigs (n = 36, 7.61 ± 0.40 kg BW) were randomly allotted to one of three treatments: a corn-soybean meal control diet (CON), and two diets supplemented with 500 mg/kg of Bacillus spp. strain 1 (PRO1) or strain 2 (PRO2), respectively. The experiment was conducted for 28 d, including 7 days before and 21 days after the first inoculation (d 0). The doses of F18 E. coli inoculum were 10P < 0.05) BW on d 7 and 14 PI, greater (P < 0.05) ADG from d 0 to 7 and d 7 to 14 PI, compared with pigs in CON. Pigs in PRO1 had milder (P < 0.05) diarrhea on d 2 and 3 PI compared with pigs in CON. However, no differences were observed in growth performance and diarrhea score between PRO2 and CON groups. Supplementation of PRO1 decreased (P < 0.05) lymphocyte counts on d 7 and 14 PI, compared with CON. Supplementation of PRO2 reduced (P < 0.05) lymphocyte percentage on d 14 PI in comparison with CON. In conclusion, supplementation of Bacillus spp</em>. reduced systemic inflammation of weaned pigs infected with F18 E. coli, with PRO1 significantly enhanced growth performance of pigs.