Abstract: A first aspect of the invention relates to the bacterial species Roseburia hominis for use in: regulating the immune system of a subject treating an immune disorder; treating an intestinal disorder; improving intestinal microbiota; regulating the innate immune system of a subject; regulating the adaptive immune system of a subject; regulating appetite in a subject; promoting Tregs and immune tolerance; promoting gut health in a subject; and/or maintaining immune homeostasis in a subject. Further aspects of the invention relate to compositions comprising Roseburia hominis.

Abstract: A first aspect of the invention relates to a porcine lactic acid bacterial strain, wherein said bacterial strain is characterised by one or more of the following characteristics: (i) the ability to exhibit antimicrobial activity against E. coli; (ii) the ability to exhibit antimicrobial activity against S. enteritidis; (iii) the ability to suppress inflammation in IPEC cells induced by 12-0-tetradecaboylphorbol-13-acetate (PMA); (iv) the ability to block the attachment or invasion of IPEC cells by S. enteritidis; (v) the ability to block the attachment or invasion of IPEC cells by E. coli; (vi) the absence of antibiotic resistance to one or more antibiotics selected from the following: ampicillin; cefotaxime; chloramphenicol; erythromycin; gentamicin; tetracycline; vancomycin; metronizadole; nalidixic acid; and kanamycin; and (vii) the ability to exhibit heat stability when subjected to three cycles of heating, each cycle comprising heating at a temperature of 70° C. for a period of 15 minutes.