The disclosure provides compositions comprising one or more isolated LDH-deficient mutans streptococcus strains and one or more isolated S. oxalis strains and/or one or more isolated S. uberis strains. Compositions of the disclosure are useful to maintain oral health, by for example treating and/or preventing one or more symptoms of dental caries, periodontitis and/or other oral cavity diseases or wounds.

The invention includes methods and compositions for treating an animal to inhibit the incidence and growth of E. coli O157:H7 and other pathogenic bacteria. The treatment method comprises administering a therapeutically effective amount of Lactobacillus animalis or one or a combination of a number of other probiotic bacteria to an animal. An alternative treatment method comprises administering a therapeutically effective amount of a lactic acid producing bacterium such as Lactobacillus animalis in combination with a lactate utilizing bacterium such as Propionibacterium freudenreichii.