Use of nitrooxy organic molecules in feed for reducing methane emission in ruminants, and/or to improve ruminant performance

A feed composition or feed additive comprising as an active compound at least one organic molecule substituted at any position with at least one nitrooxy group, or a salt thereof as defined by formula (I) an effective amount between about 1 mg to about 10 g/kg of the feed composition or feed additive sufficient to reduce formation of methane emanating from digestive activities of ruminants and/or to improve ruminant performance:

• wherein Y is an organic molecule of the following composition:
• CaHbOdNeSg,
• wherein
• a is comprised between 1 and 25,
• b is comprised between 2 and 51,
• d is comprised between 0 and 8,
• e is comprised between 0 and 5,
• g is comprised between 0 and 3, and wherein
• nitrooxy alkanoic acid, and/or derivatives thereof as defined by the formula (II) are excluded,
• wherein
• u is comprised between 0 and 23 and, wherein if u≠0, the carbon chain is a linear, a cyclic, or branched linear or cyclic aliphatic carbon chain which may be mono- or polyunsaturated and in any isomeric form,
• Z is independently O, NH, or N—R3, wherein if R1≠H, Z—R1— represents an ester or a secondary amide derivative,
• R1 is independently, hydrogen or a saturated straight, cyclic or branched chain of an alkyl or alkenyl group containing 1 to 10 carbon atoms,
• R2 is independently, hydrogen or a saturated straight or branched chain of an alkyl or alkenyl group containing 1 to 23 carbon atoms, and
• R3 is independently, hydrogen or a saturated straight, cyclic or branched chain of an alkyl or alkenyl group containing 1 to 10 carbon atoms.