Greater Sydney Local Land Services (LLS) has issued a warning for livestock owners in the Hawkesbury following a spate of fatal poisonings from weeds.
Weeds can be toxic to livestock and producers are being asked to monitor paddocks for new weeds in flood impacted areas.
LLS District Veterinarian Dr Aziz Chowdhury responded to calls for assistance following the sudden deaths of 18 cattle on flood affected properties in the Hawkesbury.
"Investigations revealed the cause of death was severe liver damage and kidney failure resulted from the consumption of lantana," Dr Chowdhury said.
"All types and parts of lantana are considered poisonous to stock. Red-flowered lantana is most dangerous. Stock poisoning is common. It happens most when new animals are introduced into lantana areas and there is no other feed available."
He said four to eight grams of the dried plant per kilogram of live weight was a toxic dose, but as little as two grams per kilogram body weight could cause the toxicity.
"Cattle used to grazing lantana-infested land are less likely to eat it however due to the recent flooding emergencies in our region the prevalence of new weeds in impacted paddocks has risen dramatically and we need producers to be on alert," Dr Chowdhury said.
Early symptoms of lantana poisoning include depression; loss of appetite; constipation; frequent urination; jaundice; inflamed eyes with a slight discharge; mouth area becoming inflamed, moist, and very sensitive, with a pink nose; and bare skin becoming very sensitive to light, red and swollen, or may crack, turn black, and die.
Stock usually dies one to four weeks after symptoms appear. Dr Chowdhury said it was a slow and painful death caused by liver and kidney failure.
"Look out for the symptoms but also look out for new and unusual plants that may cause fatalities," he said.
"If you notice any of the signs, you should seek veterinary assistance immediately."
Dr Chowdhury said rapid treatment with a drench of 2.5 kilograms of activated charcoal could be effective if given early in the course of the poisoning. Electrolytes should also be given to alleviate the dehydration.
Visit NSW Weedwise for more information at weeds.dpi.nsw.gov.au
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