DNA marker test tracks down rogue bovine genes

DPI geneticists have developed a DNA marker test to track down rogue genes and have already found those responsible for a slight defect in Australia's Jersey cow herd. Some Jerseys are born with slightly turned snouts - known as 'squiffy'. The DPI test is able to determine if the sire or dam is the carrier of the defect.

DPI genomics expert Ben Hayes said if farmers notice any defects, DPI now had a really powerful way to track down their origin.

"With this marker test you can tell if a bull or a cow is a carrier of this particular defect," Dr Hayes said. "As long as we've got DNA from the bulls, we can take DNA from a calf and match that very accurately."

The research, undertaken at the Victorian AgriBiosciences Centre at Bundoora, will help improve the reliability of Jersey genomics and help detect defects.

The Australian Dairy Herd Improvement Scheme has been testing Jersey genomic breeding values with the new DNA data and recorded reliability increases of 27% up to 40% in yield traits from the parent average.

Dr Hayes, the DPI's statewide leader of computational biology, said farmers need to more easily track cow genetics as their herds grow larger.

"The information could also be used to prevent in-breeding in dairy herds," he added.

He praised the involvement of Jersey breeders who assisted the researchers in their work. A request for proven bull semen saw more than 400 straws submitted.

"It more than doubled the data set we had available for Jerseys," he said.

For more information, contact the Australian Dairy Herd Improvement Scheme on (03) 8621 4240.