Genomic testing and improvement are helping one Queensland dairy farmer reduce his annual herd replacement rate, cut heifer rearing costs and enhance the health of his animals.
Paul Roderick, his parents David and Gwen and staff members Steph Van Der Westen, Michael Sweetnam, Michael Turner alongside casual staff — vet students from the University of Queensland Gatton campus — milk from 220 to 370 cows year-round at Harrisville, an hour south-west of Brisbane.
The farm business started genomic testing six years ago as a tool to change subjective animal retention judgements into objective, scientifically backed farm business decisions.
But DNA testing has delivered much more than anyone had ever hoped.
It enabled the Roderick farm to use genetics to solve long-term challenges with dairy farming in Queensland such as cost and climate pressures.
“Our herd turnover rate is about a third a year and that has a lot to do with animal health, dealing with hot weather and wet summers,” Paul said.
“If we can breed a better cow, a more functional cow, using DataGene’s Balanced Performance Index and Health Weighted Index, we could see that reduce.
“Even if it came down by five per cent, it ensures we can rear better heifers while saving money as we don’t have to rear as many.”
Retaining 10 less heifers each year would save the Rodericks $20,000 — or $2000 a heifer — in rearing costs.
Saving rearing costs helps offset the cost of genomic testing for the Rodericks.
Testing 150 calves a year costs $7500.
They anticipate they’ll be testing less into the future thanks to more targeted use of sexed and beef semen.
Time-saving and better decision making also delivers a return on the investment in genomic testing, although it’s not as easy to measure, according to Paul.
“Quantifying something subjective into something that’s actually scientific and accurate is difficult, but it’s something that I value,” he said.
“For example, we now have data about our herd so when we get bull catalogues from semen companies we work from our data, not anyone’s opinion. It’s a way to avoid bias and it allows us to deal across companies and different bulls because it's scientific and index based.”
Using data for breeding decisions also helps Paul and his staff have clear and objective conversations about animal retention and the breeding strategy.
He said this ensured everyone was on the same page when it came to breeding and no matter who selects the bulls, it was going to meet their farm business requirements.
Steph manages the Roderick animals from when the calves are born until they enter the milking herd.
She said the heifers that were genomic tested last year and the milking herd would be joined this year according to their genomic results.
Phasing out bobby calves
This sexed semen and beef strategy would not only help phase out bobby calves, it is also set to improve genetic gain, according to Steph.
The strategy includes breeding the top 25 per cent, according to their genomics, twice to sexed semen, the middle 50 per cent once to sexed semen with the remainder to beef.
The portion of the herd bred to beef will be adjusted according to demand for dairy heifers, Steph said.
For her, reducing the number of heifers reared as replacements for the dairy business saves time and money, but it also enables the redirection of funds.
“If we aren’t keeping as many heifers and not as many are being bred, we have the option of not having to buy so many dairy semen straws,” Steph said.
“This means we can invest more money into better bulls — better genetics — to breed the ones we are retaining.”
Part of Steph’s job includes genomic testing the calves when they are sedated for disbudding.
She said taking an ear notch sample was a simple process, while analysing the data has required extra learning.
“With genetics in general there’s a lot to get your head around,” she said.
“That’s why field days and information sessions have been great.”
Steph and the team at the Roderick farm use DataGene’s DataVat herd software for management and the genomics software from their service provider to interpret the DNA results.
Game-changer
In the same way artificial insemination became a “game-changer” on-farm for his father David’s generation, Paul’s confident genomics will do the same for modern dairy farmers.
With trust in the science, he’s viewing it as a long-term investment for his own business and the entire Australian dairy industry.
“There’s been a significant amount of dairy farmer levy money put through genomics and this has also been done independently with world leading scientists in the field,” Paul said.
“Now, the practical application we’ve seen in the past five or six years is justifying this investment.”
For his own business, Paul anticipates the role of genomics in decision making and breeding direction will only increase as more data becomes available.
He’s especially interested in DataGene’s work around breeding for heat-tolerant cows and further investigating the Sustainability Index as a tool to reduce emissions intensity.
The Roderick farm has already adjusted its calving pattern to avoid the hotter months.
Cows mostly calve from March through to October, but Paul believes breeding for heat-tolerant animals will further assist them in managing fluctuating weather conditions.
“We are trying to use genetics on our journey to give us a hand with the challenges we face as dairy farmers in Queensland,” he said.
“The early indications are that it is working. We are breeding better young animals.
“Genomics is part of our tool kit. It isn’t everything, we still must get cows in calf, feed them well and everything else, but it is part of our puzzle.”