A method of mimicking a phenotype of a first ruminating animal in a second ruminating animal is disclosed. The method comprises administering to the second ruminating animal a microbial composition comprising a plurality of microbes having a signature which is statistically significantly similar to the microbial signature of a rumen microbiome of the first ruminating animal, wherein the first and the second ruminating animal are of identical species, thereby mimicking the phenotype of the first ruminating animal in the second ruminating animal.