Abstract: The present invention relates to a genetic marker used to distinguish amongst animals a trait for milk producing capabilities and milk composition. The marker is a mutation in the gene encoding somatotropine (also called growth hormone)-receptor (GH-R) at amino acid position 279 (a phenylalanine to tyrosine substitution in the transmembrane domain) which results in two forms of somatotropin receptor existing in bovine. The invention also pertains to methods and kits for determining whether a bovine has a genotype indicative of a trait of superior milk yield or a genotype indicative of a trait of superior milk composition, based on the analysis of said genetic marker.

Abstract: Methods and kits for determining milk production potential in an animal by analyzing the polymorphism of its Pit-1 and ?-casein genes. More particularly, the invention concerns a method for identifying a mammal with a genotype that is indicative of advantageous milk production traits, including a step for analyzing the polymorphism of the Pit-1 and ?-casein genes of the mammal, in which the simultaneous presence of allele A and/or T of the Pit-1 gene and allele B of the ?-casein gene is indicative of high potential for milk production and protein production in the mammal.

Abstract: The present invention relates to a genetic marker used to distinguish amongst animals a trait for milk producing capabilities or muscular beef producing capabilities, said genetic marker comprising a mutation in a fragment of a Pit-1 gene. After digestion with a restriction endonuclease, three allele patterns are observed, the fully digested pattern being indicative of a trait for muscularity in said animal, while the intermediate digested / nondigested pattern or the nondigested pattern being indicative of a milk producing trait in said animal. A process and kit using this genetic marker is also disclosed.

Abstract: A peptide construct including all or part of the sequence between positions 104 and 113 of growth hormone GH, or a homologous sequence cross-reactive therewith, is disclosed. The peptide fragment is covalently bonded to a transporter peptide and/or an adjuvant, and is capable of having an in vivo potentiating effect on the biological activity of said growth hormone.

Abstract: The invention concerns a genetic marker used to distinguish amongst animals a trait for milk producing capabilities or meat producing capabilities said genetic marker comprising a mutation in a fragment of a Pit-1 gene wherein three patterns of alleles are observed in which one of said allele patterns was fully mutated and being indicative of a trait of muscularity in said animal, while the two other allelic patterns, one being mutated and non/mutated, the other being non-mutated/non-mutated being indicative of a milk producing trait in said animal.