Work being carried out by university researchers in collaboration with dairy farmers is creating a genetic tool which will enhance the selection process when it comes to fat colour in the meat of Jersey bobby calves.
During the breed’s development, Jersey cows were selected for creamy milk colour.
In the same way, Jersey cattle – now one of the world’s oldest dairy breeds – tend to produce yellow-coloured fat in and around their muscles, due to the level of carotene the fat contains (which provides colour).
However, Jersey cattle can be genetically selected to produce a whiter fat, which is better received by certain markets.
If dairy producers can tweak the selection of their bull to produce offspring that genetically exhibit whiter fat, then the beef from these calves will be easier to sell.
Dr Cameron Clark, University of Sydney, said genetic selection for fat colour could prove useful as a marketing tool to enhance the value of Jersey bobby calves.
“Our main research focus now is on developing low cost, high welfare rearing systems to go alongside these findings for farmers with a primary focus on Jerseys. We want to determine the interaction between diet type and genetics with the aim of developing low cost, high profit, high welfare systems for farmers,” Dr Clark said.
“There is a good opportunity for these Jersey rearing systems to produce high eating quality meat, given the Jersey breed is ranked highly for the ability to produce meat with marbling.”
The work is being done in collaboration with Prof Cynthia Bottema, University of Adelaide, and the NSW Dairy Innovation Group, led by a group member and Boambee farmer, Jason Bake.
About 100 straws of Jersey semen and the same number of Hlostein straws, donated by Genetics Australia, were used to extract DNA for analysis.
It turns out two genes affect fat colour: beta, beta-carotene 9 ‘, 10 ‘ – dioxygenase, or BCO2, and RDHE2 (retinal short-chain dehydrogenase reductase).
BCO2, which also affects milk colour, is responsible for more than 40 per cent of variants in DNA, while the other gene only accounts for eight to 17 per cent of phenotypic variation.
Together these two genes create an additional 7pc variation, so identifying these markers in Jersey bull semen can lead to more accurate Breedplan information when selecting for fat colour.
“We are now seeking funding and industry partners to further our work,” Dr Clark said.
“We are keen to bring more farmers on board. We need to harness good ideas.”
Dairy producers should email their interest to: cameron.clark@sydney.edu.au
Finding a purpose for Bobby calves
Dairy farmer, Jason Bake, already has a market for his bobby calves, as a result of some lateral thinking, but can see a better future for steers born to Jersey dairy cows.
In recent years Mr Bake, who farms at Bonville near Coffs Harbour, has put a Waratah-bred Speckle Park/ Brahman bull over his three-way cross dairy heifers with the intention to deliver easy calving for young cows.
The result is a dairy steer with inherent marbling combined with beef genetics that build volume. However, the selling point for Mr Bake is the pretty hides thrown by the Speckle Park genetics.
“I have filled my order book for all my bobby calves this year and they’re not born yet,” he said, noting good demand from owners of lifestyle blocks keen to appreciate the beef game with just one or two pretty animals.
Beyond this Mr Bake sees a more robust future in the marketing of Jersey-cross steers with an emphasis on fat color, as well as marbling.
Already he sells vealers to the Northern Co-operative Meat Company at Casino and he can see that line expanding as more consistent beef/dairy steers are produced.
