Probiotics for reducing methane production

A probiotic composition comprising at least one organism and a carrier, which organism is characterized by having the ability to metabolize carbohydrates and/or their products and by production of less than 0.5 mole hydrogen per mole of metabolized carbohydrate equivalent, wherein said composition is characterized by reducing methane production when administered to a ruminant,

• wherein said at least one organism optionally comprises a mixture of organisms,
• wherein said at least one organism is optionally further characterized by having at least one property selected from the group consisting of being capable of producing a cellulose-hydrolyzing enzyme, having a maximal growth rate constant of at least 2.0 hour−1;
• being capable of non-oxidative glycolysis;
• being capable of consuming lactate and forming at least one of acetate and butyrate;
• being capable of consuming lactate and forming propionate;
• being capable of producing an organic acid or a salt thereof;
• producing an organic acid or salt thereof, wherein said organic acid is selected from the group consisting of propionic acid, butyric acid, lactic acid, formic acid, acetic acid, oxalic acid and combinations thereof;
• having at least one property selected from the group consisting of butanoate metabolism, obligate anaerobic growth, gas fixation via the reductive acetyl-coenzyme A pathway, tolerance to bile salts at concentration greater than 0.05%, tolerance to pH of less than 3.5, and self-aggregation.