The present invention relates to methods of treatment or prevention of irritable bowel syndrome (IBS), abdominal pain, disordered defecation, and FODMAP intolerance, by administering a preparation containing probiotic strain of Lactobacillus plantarum (Lactiplantibacillus plantarum) DSM 33363, or the preparation in combination with Lactobacillus plantarum (Lactiplantibacillus plantarum) DSM 33364, Lactobacillus paracasei (Lacticaseibacillus paracasei) DSM 33373, Lactobacillus resuteri (Limosilactobacillus reuteri) DSM 33374, Bacillus megaterium (Priestia megaterium) DSM 33300, Bacillus pumilus DSM 33297, and Bacillus pumilus DSM 33355, as viable cells or cytoplasmic extract thereof. A foodstuff composition containing the preparation disclosed herein is also described.

Provided herein, inter alia, are compositions of organic acid-producing microorganisms and methods of making and using the same to inhibit pathogenic bacterial populations in the gastrointestinal tracts of an animal and additionally promote improvement of one or more metrics in an animal, such as increased bodyweight gain, decreased feed conversion ratio (FCR), improved gut barrier integrity, reduced mortality, reduced pathogen infection, and reduced pathogen shedding in feces.