Inherited diseases of Australian Holstein-Friesian cattle.

Inherited disorders are of major importance in Holstein-Friesian cattle, a breed that now dominates the global dairy industry. Recent developments in the breed reflect intensive selection programs for production traits, identifying elite sires whose genotypes are rapidly spread worldwide through the use of breeding programs involving advanced reproductive technologies. These elite sires carry mutations responsible for disease. Consequently, the mating of descendants of an elite sire (as with any sire) substantially increases the risk of producing defective progeny. The important inherited disorder citrullinaemia was disseminated globally in the 1970s and first reported in Australian Holstein-Friesians. However, a range of inherited disorders more recently recognised internationally in this breed have remained unreported in Australia, although recent genotyping studies suggest they have probably occurred. A survey of these disorders suggests a decline in surveillance for such diseases in Australia. Clinical and pathological descriptions are presented to enable practitioners and producers to recognise and report these disorders, and a proposal is advanced to establish a health program to manage this issue.