Gene regulating milk production revealed

- Last updated on GMT

Related tags: Cattle, Gene

Scientists at the food research body MTT Agrifood Research in
Finland, in collaboration with University of Liège in Belgium, have
located the gene that regulates total yield, protein and fat
content of milk.

Scientists at the food research body MTT Agrifood Research in Finland, in collaboration with University of Liège in Belgium, have located the gene that regulates total yield, protein and fat content of milk.

The scientists claim to have found a variation in the growth hormone receptor gene in the bovine chromosome 20. The variation in the receptor gene is associated with a major effect on milk yield and composition in Ayrshire, Holstein and Jersey cows.

Dr Johanna Vilkki of MTT maintains that developing associated markers for genes that affect milk traits is not highly prioritised in breeding since it is relatively easy to improve these traits by conventional selection.

She emphasises the fact that the value of the finding is scientific. This is the second time that a clear quantified association has been demonstrated between a single gene and bovine milk production.

The researchers claim that the present discovery will help breeders select bulls siring daughters with more economical milk production. The 'water' version of the gene results in a 200 kg increase in annual production per cow, respectively decreasing the fat and protein content. The more cost-effective version of the gene will increase the average protein content in milk by 0.06 percentage units and the fat content by 0.15 percentage units, albeit at the expense of total milk yield. In 2002 the annual yield of the Finnish Ayrshire cow was 7,381 kg of milk with a fat percentage of 4.36 and a protein percentage of 3.36. According to Dr Vilkki, the vast majority of Finnish Ayrshire cattle are already carrying the more advantageous form of the gene.

The sparse mapping of the entire genome of the Finnish Ayrshire, completed by MTT about two years ago, provided the basis for the present study.

The study - launched in 1999 - was part of the EU biotechnology programme project EURIBDIS, which gathered together six European research groups. Full findings of the research can be found in the January 2003 issue of the journal Genetics.

Related topics: Science

Related news

Follow us

Products

View more

Webinars