LIC discovers small calf gene

David Hemara, acting chief executive of LIC, says: "This is an important discovery. Identifying the gene means we can start managing a problem which has existed on farms for decades."

The small calf syndrome affects predominantly holstein friesian and a lesser number of crossbred animals. Incidence of the syndrome has been assessed to be around one to two affected calves in the average 400 cow New Zealand herd per year.

David Hemara said that LIC's large genetics database and ongoing research programme enabled the Cooperative to "go back 30 years screening the DNA of our bulls, and beyond that through pedigree records. That research suggests the genetic variation existed in the early 1960s and possibly before then. We can't be sure of when or where it started."

David Hemara said LIC understands that the gene's discovery will be of interest to dairy farmers with Holstein Friesian or crossbred animals.

"Our programme of gene discovery and DNA sequencing is improving our ability to isolate negative genes. This is a good thing for the dairy industry."

Eradicating the genetic variation from the national herd is a priority for genetics companies and CRV Ambreed chief executive, Angus Haslett, emphasised the discovery's importance "to all New Zealand breeding companies and farmers".

"Over the years a number of genetic variations have been discovered and managed out of the industry and this will be no different. CRV Ambreed will work with LIC to manage this genetic variation so its impact is minimised on New Zealand farms in the future."

David Hemara said "This is the latest in a range of genetic variations which have been discovered, and largely eliminated, over the years. Diseases like CVM and BLAD used to be present in New Zealand herds but their incidence has been reduced thanks to their discovery and managed removal from the national herd.

New Zealand Animal Evaluation Ltd (NZAEL), the DairyNZ subsidiary company that manages the national breeding objective for New Zealand dairy cattle, is encouraging and welcoming moves by genetics companies LIC and CRV Ambreed to work together and manage small calf syndrome out of the industry.

NZAEL spokesman and DairyNZ strategy and investment leader, Dr Bruce Thorrold, says the problem has been identified through farmer reporting, combined with the latest genetic screening tools. "Each of these is vital to the industry, and this latest response emphasises the importance of data capture and sharing," he says.

"While this is a very small problem on New Zealand dairy farms right now, it is encouraging to see that the cause has been identified, that the companies are jointly working on the issue and that it will be solved as a priority," says Dr Thorrold.

"The breeding companies' strategies will prevent the problem becoming more widespread."

Dr Thorrold says recessive genes occur in all populations, and the power of New Zealand's on-farm data collection and research activity means that these effects are identified while still at low levels.

"That means the issue can be managed at an industry level in a way that just wouldn't be possible by individual farmers. Farmers' confidence in the use of artificial insemination (AI) should be increased by this result."

He says NZAEL expects all the breeding companies to work together to screen bulls, share information and provide farmers with good advice this spring about potential small calves and mating choices. NZAEL will be monitoring this on behalf of farmers. It is also advising farmers to focus on their record keeping.

"It is important for farmers to keep accurate records of parentage.

"Our research shows that with the mis-tagging and mis-recording that currently happens on dairy farms, around 23% of herds, or around one million New Zealand dairy cows, are identified to the wrong sire. The LIC datamate or CRV Ambreed's sire match can only protect cows whose parentage is accurate," he says.