Vets on the Northern Rivers are warning cattle producers to look out for deadly cow disease, Yersiniosis, also known as mud scours.
They say they have seen cases of the bacterial disease on several North Coast properties in recent weeks but antibiotic treatments are available and effective.
All cattle breeds are vulnerable to Yersiniosis but risks are higher for Brahmans and Brahman crosses.
The disease is not a threat to human health but people are advised to wash their hands after handling infected cows.
North Coast Local Land Services District Veterinarian Phil Kemsley says outbreaks of Yersiniosis will often impact several cows in a herd at once, usually adult cows, and early diagnosis is critical.
The Yersinia bacteria thrive in low temperatures and oxygen levels typical in poorly drained paddocks and is often found in dry grass contaminated with mud.
During dry spells, hungry cattle are more likely to explore muddy places such as bogs and dams for food and Dr Kemsley says this can lead to feed hay contamination.
Yersiniosis symptoms vary but cows suffering early stages of the disease often have a fever that may resemble other fevers such as ‘three-day sickness’, says Dr Kemsley.
‘In some cases, affected cattle are found dead but in good body condition,’ he says, ‘others have diarrhoea for several days, which results in dramatic weight loss.’
He says cows with Yersiniosis should be quarantined in a separate paddock with healthy cattle ideally moved to a paddock with better drainage.
Yersiniosis usually stops once spring and warmer conditions arrive.