Testing has revealed that hay with high levels of prussic acid and nitrates was the cause of death of cattle on a property south of Stanthorpe last week.
Fred Pratt, Grabond Holdings, Eukey, fed the hay, sourced from Kalbar, to cattle last week.
He said 10 cows and 23 calves that had fed on the hay survived.
"The hay had been tested but it must have been one biscuit that was the problem," he said.
"There was hay left in the feeder afterwards but that was tested and came back ok.
"It's not good but it's happened.
"The supplier has rung around and as far as we know everyone else who has bought these particular bales have had no problems.
"If the supplier has tested the ends of a bale, does he test in the middle too? Just how far do we go with testing?"
Biosecurity Queensland last week ruled out anthrax as a possible cause and today a spokesman warned livestock owners to be cautious when sourcing fodder supplies.
“As drought conditions persist in much of southern Queensland and large areas of New South Wales and Victoria, hay is increasingly being made from failed grain crops and drought affected forage crops,” he said.
“In hot, dry conditions, crops that would normally provide a valuable source of feed, can accumulate high levels of prussic acid and nitrates.
“Even after being cut and made into hay, the levels of these two naturally occurring chemicals can still be high and toxic to stock, as was the case in this recent Stanthorpe incident.”
Southern Downs MP James Lister said he felt sad for the producer whose herd had been impacted.
“When you’ve got the drought the way it is… it’s more likely we’ll see incidents like this,” he said.
“The tragedy of this is we’ve got producers that are really hurting, producer have been trying to feed their stock to keep them alive.”
Mr Lister said Biosecurity Queensland should be commended for its quick work to find the cause of the deaths.
Agforce livestock policy director Renata Berglas said they were sorry to hear of the stock losses and that producer should ask questions about the weather conditions hay had been grown in when they were buying.
“It’s also important if you’re drought feeding cattle to keep it a nice continuous flow of feed,” she said.
Livestock management consultant Desiree Jackson said she was aware of incidents of toxic hay killing cattle and sorghum in particular could often be susceptible to high levels of prussic acid and nitrate during dry times.
Ms Jackson said livestock producers could ask for testing to be done before they bought hay, but growers could also be proactive.
“It’s in their interest to actually test on farm rather than hear about the problem later because there have been deaths,” she said.
“From a producer’s point of view if they are feeding cattle hay, it’s a good practice to have sulphur to feed them as well and a lot of people do this.
“It allows the liver to detoxify the nitrates a little bit faster.”
Ms Jackson said it was a good policy to test, even if producers were eager to get the hay on the ground quickly.
“When stock are in a weaker condition, they’re basically more vulnerable to toxicity,” she said.
Biosecurity Queensland has urged livestock owners to always ask vendors if hay has been tested and to use a commodity vendor declaration.
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