Breeding a better dairy cow for Australian conditions requires a balanced approach according to Agriculture Victoria's principal research scientist Jennie Pryce.
But she says the three DataGene selection indexes released in 2015- which incorporate production, health, fertility, survival and functionality traits- have made bull selection fairly simple.
About 80 per cent of farmers are using the profit-driven, Balanced Performance Index, while the Health Weighted Index and Type Weighted Index are also proving useful for those conscious of health or conformation in their herds.
Dr Pryce told the International Red Dairy Breeds Federation Conference in Mount Gambier this week a new revolution was coming with researchers using phenotyping to help farmers breed cows with lower risk of animal health issues such as mastitis.
By successfully breeding for fertility, which also has low heritability, we have shown it is possible to still make progress.
Dr Pryce predicts a breeding value for mastitis risk that includes farmer collected mastitis records, somatic cell count and udder depth could be available within a year or so but one for lameness was further off.
"It is much harder to work with these traits where the genetic component is not high but by successfully breeding for fertility which also has low heritability we have shown it is possible to still make progress," she said.
She says more farm data, particularly clinical cases of mastitis and information on lame cows in a herd, not just those treated with antibiotics, would speed up the development of these new breeding values.
There may also be opportunities to use other data sources, such as screening milk using mid-infra-red spectrometry (part of routine herd-testing). "Certain profiles may tell us which cows are at risk," she said.
Genomics has created many opportunities for the Australian dairy industry in recent times especially accelerating genetic gain according to Dr Pryce.
Even more beneficial was the ability to select for hard to measure traits such as feed efficiency and heat tolerance.
She said Australia had become a world leader in breeding for feed efficiency, with the Feed Saved breeding value released in 2015 .
Incorporating vast amounts of feed efficiency data from reference populations in the Netherlands and the United Kingdom had made this figure more robust and Dr Pryce said DataGene and Agriculture Victoria were working to expand this further.
Heat tolerance genomic breeding values released by DataGene in late 2017 were also helping farmers breed dairy cattle better suited to Australian conditions with some bulls found to sire daughters less likely to see a drop in milk yield as temperatures rise.