Prevalence of two recessive genetic disorders in Marchigiana, Romagnola and Chianina cattle breeds in the period 2022-2024.

A certain number of inherited diseases and traits in cattle have been characterized at the molecular level, identifying the causative gene variant in the DNA locus. Also the three main native Italian beef cattle breeds located in the Apennine Mountains (Chianina, Marchigiana and Romagnola) are interested by this discovery. Genetic selection in Italian beef cattle is implemented by the National Association of Italian Beef Cattle Breeders, with the aim of improving meat production, growth ability and muscle development. Contextually, bovines, particularly those with pedigree registered in the genealogical book, have to be constantly monitored for the main congenital and hereditary disorders, among them "Paunch Calf syndrome" and "Congenital Ichthyosis". Paunch Calf Syndrome (PCS) is associated with a missense variant in the KDM2B gene on chromosome 17, while Congenital Ichthyosis (CI) is caused by an insertion of a cytosine in FA2H gene causing a frame-shift on chromosome 18. The aim of this work was to present an update of the prevalence of PCS in Marchigiana and Romagnola breeds and of CI in Chianina breed, in the Central Italy territory. In the period 2022-2024, a frequency of 6.67% heterozygous PCS carriers was registered, while for CI, in 2024, a prevalence of 5.67% heterozygous carriers was observed. These findings show that cattle should be constantly monitored and the genotyping of causal variant should be used, at least for excluding risk matings of carriers to prevent further animal losses due to these two congenital disorders.