27 July 2001

CVM is caused by single gene

ONE in every eight calves born when a bull carrying the complex vertebral malformation (CVM) gene is mated with the daughter of another CVM bull will die before or just after birth, according to Dutch research.

This indicates the genetic defect is caused by a single recessive gene, says breeding company Avoncrofts Emrys John. Knowing this allows it to be eliminated by producers when they select bulls for use.

CVM can be easily eliminated by avoiding mating daughters of a CVM carrier bull with another carrier bull, says Mr John.

"A test is available to screen bulls for the disease – assuming breeding organisations provide information on bulls to allow producers to make an informed choice."

Mr John, therefore, urges producers to seek CVM details on each bull they consider for their breeding programme and breeding organisations to publish CVM test results for sires. &#42