Genetic variants of beta-casein, a protein of cow's milk, can be classified into two groups, A1 and A2, based on the specific amino acid in position 67 of the protein. This A1/A2 group designation may be of interest to breeders developing herds for human health benefits.
Bulldog dwarfism is a lethal genetic defect of Dexter cattle. Affected fetuses have severe disproportionate dwarfism, a short vertebral column, a large head, and are naturally aborted around seven months of gestation. The two known mutations are specific to Dexter cattle and may be present in Dexter crossbreds.
Bulldog dwarfism is a lethal genetic defect of Miniature Zebu cattle. Affected fetuses have disproportionate dwarfism, a short and compressed vertebral column, a large head, short, stocky limbs, and are naturally aborted around seven months of gestation. The mutation that causes this defect is specific to Zebu cattle and is different from the Dexter mutations.
The pale cream/white coat color of Charolais cattle is produced by a mutation that has a dosage-dependent effect on pigments, with a single allele diluting black to gray and red to pale red, and a double dose producing the breed's typical white coat.
Holsteins with the Dominant Red variant have red and white coats inherited in an autosomal dominant fashion. The gene underlying this coloration is independent from the other major gene (MC1R) that controls black and red color in Holstein cattle.
The Melanocortin 1 Receptor (MC1R) gene (also called Extension) controls the production of black and red pigments in the coats of domestic cattle, creating base colors that may then be further modified by other genes.
This DNA-based parentage test uses microsatellite marker analysis to compare the DNA profile of an offspring to the profiles of possible parents. The markers reported include the 12 ISAG-recommended markers for cattle. Genotypes follow the international nomenclature standard for cattle.
Paunch calf syndrome (PCS) is an inherited lethal defect of Romagnola cattle characterized by abnormal development of multiple organs, craniofacial deformities, an enlarged fluid-filled abdomen, and liver fibrosis. Affected calves are usually stillborn.
Pulmonary hypoplasia with anasarca (PHA) is a lethal genetic defect characterized by incomplete development of the lungs and severe subcutaneous fluid accumulation, leading to abortion or the birth of a dead calf.