Acute bovine liver disease
With the abundant pasture growth of recent months, the light stocking rates on many properties, and the large amount of dry standing feed, coupled with autumn breaking rains, farmers are advised to be on the lookout for acute bovine liver disease (ABLD).
ABLD was first noted in Tasmania in 1987, and in recent years several incidents have been seen in South-West Victoria, SouthEast South Australia, Gippsland, and NorthEast Victoria.
There has been a recent case reported on a property in North-East Victoria.
Cases can result in a catastrophic number of deaths in cattle.
It has not been described in other species. The condition has been seen in both beef and dairy cattle.
It can show up in a range of forms.
In the worst incidents there has been a sudden onset of deaths in cattle over six months of age.
The typical signs of photosensitisation, such as depression, agitation, raised temperature, and reddening of the lighter coloured skin and udder may be seen prior to death, and are common amongst the survivors.
The pathology is consistent with an acute liver disease.
Cases are consistently linked to access to a plant called Rough Dog’s Tail (Cynosurus echinatus), also known as Manifold Grass.
It appears the plant is a likely carrier of a fungal toxin which briefly proliferates given the right set of environmental conditions.
There is no known direct cure of affected cattle.
There is some evidence, if affected cattle are treated with medication to alleviate the effects of photosensitisation, it may help.
Several common features have been seen during each outbreak:
Access to Rough Dog’s Tail prior to the onset of clinical signs. Rough Dog’s Tail is typically found on steep, hilly paddocks;
Access to paddocks with an abundance of dry standing feed that had been spelled for over three months; and,
Significant season breaking rain in late autumn or early winter at the time of the introduction of cattle onto those paddocks.
For further information please contact your local veterinarian or Agriculture Victoria Veterinary or Animal Health Officer.