LAUSR

This study determined the supplemental effects of Lactobacillus fermentate (LBF, Adare Biome, France) on intestinal health and prevention of post-weaning diarrhea caused by F18 +  Escherichia coli in nursery pigs. Sixty-four weaned pigs (6.6 ± 0.7 kg BW) were allotted in a randomized complete block design to 4 treatments: NC: no-challenge/no-supplement; PC: E. coli challenge/no-supplement; AGP: E. coli challenge/bacitracin (30 g/t feed); and PBT: E. coli challenge/LBF (2 kg/t feed). Bacitracin methylene disalicylate (BMD) was used as source of bacitracin. At d 7, challenged groups were orally inoculated with F18 +  E. coli (2.4 x 10 10 CFU) whereas NC received sterile saline solution. Growth performance was analyzed weekly, and pigs were euthanized at the end of 28 d feeding to analyze intestinal health. Data were analyzed using the Mixed procedure of SAS 9.4. During post-challenge period, PC tended to decrease (P = 0.067) ADG when compared with NC, whereas AGP increased (P < 0.05) it when compared with PC; PBT tended to increase (P = 0.081) ADG when compared with PC. The PC increased fecal score (P < 0.05) during d 7 to 14 when compared with NC, whereas AGP decreased it (P < 0.05) during d 14 to 21 when compared with PC. The PC increased (P < 0.05) protein carbonyl, crypt cell proliferation, and the relative abundance of Helicobacter rodentium when compared with NC. However, AGP decreased (P < 0.05) crypt cell proliferation and Helicobacter rodentium and increased (P < 0.05) villus height, Bifidobacterium boum, Pelomonas spp., and Microbacterium ginsengisoli when compared with PC. The PBT reduced (P < 0.05) crypt cell proliferation and Helicobacter rodentium and increased (P < 0.05) Lactobacillus salivarius and Propionibacterium acnes when compared with PC. At the genus level, AGP and PBT increased (P < 0.05) the alpha diversity of jejunal mucosa-associated microbiota in pigs estimated with Chao1 richness estimator when compared with PC. Collectively, F18 +  E. coli reduced growth performance by adversely affecting microbiota and intestinal health. The LBF and BMD improved growth performance and it was related to the enhanced intestinal health, and increased diversity and abundance of beneficial microbiota in pigs challenged with F18 +  E. coli.