Probiotic Intervention With Bacillus coagulans and Lactobacillus acidophilus in Small Animals Experimental Ulcerative Colitis: Insights From a Small Animal Model

Inflammatory bowel disease is a significant health concern not only in humans but also in companion animals and livestock, where it manifests as chronic diarrhoea, abdominal pain, and mucosal injury. Probiotics have gained increasing attention as potential therapeutic agents due to their immunomodulatory effects and ability to restore intestinal homeostasis. This study investigated the therapeutic efficacy of Bacillus coagulans and Lactobacillus acidophilus in an acetic acid-induced ulcerative colitis model in Wistar rats. Forty male rats were randomly assigned to control, colitis, mesalazine, B. coagulans, and L. acidophilus treatment groups. Disease severity was evaluated by macroscopic and histopathological scoring, colon length and weight, pro-inflammatory cytokine levels (IL-1β, IL-17), and inflammasome-associated gene expression (NLRP3, Caspase-1, IL-18, TNF-α). The results showed that colitis induction significantly increased pro-inflammatory cytokine expression and histological damage compared with controls. Both probiotics markedly reduced inflammatory markers, improved colon morphology, and attenuated inflammasome activation. Their protective effects were comparable to mesalazine, the standard treatment. These findings suggest that B. coagulans and L. acidophilus can serve as effective adjunct therapies for ulcerative colitis in veterinary practice, with potential translational applications for companion animals and livestock.