When Isaac Korpershoek selects heifers to keep for his dairy herd, his decisions are backed by science.
Subjective assessments of replacements, based on their size or appearance, have been traded for objective and data-driven judgements about the long-term profitability of these animals in his herd.
Genomics, the study of an animal's DNA, has made this possible.
But the Tasmanian dairy farmer would be the first to admit, selecting heifers from data required a different way of thinking.
"You'd normally look at a heifer and say, 'that's a big strong heifer, we will keep that one' but with genomics, I've found those heifers aren't necessarily the best ones," he said. "Genomics has changed my mindset, no longer do I say, 'that's a good one' when the data is telling me it isn't."
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Mr Korpershoek farms with his wife Angelique - a veterinarian - at Forest in Tasmania's north west.
The couple will milk 350 cows this year and calved in autumn.
Crediting Mrs Korpershoek for the farm's adoption of "science-based", proven and supported practices, Mr Korpershoek said using evidence to make business decisions was reassuring.
For the Korpershoeks, the benefits of genomic testing far outweigh the cost.
"You know that the heifers you keep are going to be superior," he said. "What's $50 (a test) to know that you are keeping the best 110 heifers that you have got."
Faster data delivery
Australian dairy farmers can now access their herd's genomic data faster and make more timely decisions about what animals to retain and sell, thanks to DataGene's new weekly genetic analysis.
Introduced this year, the updated analysis has halved the time it takes for a genotype to be evaluated and results to return to the farm. Shipping and lab analysis take a few weeks. Once the genotype has been received by the DataGene system, farmers will receive their results within nine days - in line with some of the world's largest dairying nations.
Making data-driven decisions
The Korpershoeks use the genomic data to rank heifers by their Balanced Performance Index (BPI), mastitis resistance and fertility Australian Breeding Values (ABV).
After selecting their replacements, excess heifers are sold to the export market.
In recent years, sexed semen has helped bolster the Korpershoeks' heifer numbers.
As more genomically tested females enter the milking herd, Mr Korpershoek said sexed semen would be used to join the heifers as well as the three-year-old and four-year-old cows.
This would ensure all their dairy replacements would be bred from their genetically superior animals.
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Incorporating Angus bulls into their Holstein breeding program has opened new markets for the dairy operation.
"We've had 20 to 30 people ringing up wanting beef calves," Mr Korpershoek said. "There are not many autumn calvers up our way and because we are a Friesian herd - not crossbred - there's a stronger demand for the beef-cross calves."
The Korpershoeks' calves are genomically tested at about 3.5 months of age. All calves are done in one batch and testing is combined with vaccination and drenching.
The Korpershoeks take an ear notch sample to determine their calves' genomics. Mr Korpershoek said this was easier to get a clean sample compared with extracting tail hairs.
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Adding genomics to their farm, the Korpershoeks hope to have better control over their breeding program, which would deliver benefits to their overall business.
"Basically, the gains you get in dairy farming now are a lot smaller than say 15 years ago when Dad was dairy farming," Mr Korpershoek said. "Then you could develop more land...then by feeding grain you could take cows from 5000 litres (a lactation) to 9000 litres. The gains we get now from dairy farming are a lot smaller. Those gains come from just trying to improve the herd with more trouble-free cows, ones that can get in calf, are functional and that stay in the herd.
"Obviously, you want to keep the best ones and try and sell the others to the export market. The data doesn't lie."
For more information, contact DataGene on 03 9032 7191 or email@example.com.
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