Described are the Bacillus subtilis strain deposited as DSM 32685 and mutant strains thereof which are susceptible to relevant antibiotics, have inhibitory activity against, for example, Staphylococcus, Streptococcus, E. coli and Salmonella, and have the ability to facilitate degradation of non-starch polysaccharides and thereby increase the amount of available oligosaccharides (sugar) in animal feed. Also described are compositions comprising at least one Bacillus subtilis strain of the disclosure and optionally further bacteria and/or one or more types of yeast and methods of using such compositions.