A bacterial infection which affects cows' udders and milk production is costing the dairy industry about $180 million a year, or $14,000 a farmer.
Research funder Dairy Insight said the figures - based on analysis of 166,000 cows and 1.8 million herd test records - were the first accurate picture of the true cost of mastitis.
The costs included lost production, the time farmers spent dealing with the problem and veterinary treatments of affected cows, said Dairy Insight's farm productivity investment manager Phil Urlich.
His organisation was funding further research aimed at better understanding infection, and a national mastitis advisory committee had issued best practice guidelines to farmers.
The research proved farmers could clearly make significant financial savings by getting on top of mastitis.
In an average herd where the somatic cell count (SCC) is 212,000 cells a millilitre of bulk milk, the annual per cow cost is $36. SCC measures the level of anti-bodies being produced in response to infection.
The research showed that halving that level would result in a production gain of $26 a cow.
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