FARM authorities have detected signs of exposure to the bluetongue virus (BTV) in dairy heifers at Echuca on the NSW-Victorian border.
This means a 100-kilometre BTV zone will be in place for the next 30 days around the property where evidence of exposure was found – stretching north of Moama, Mathoura, Deniliquin, and Wakool.
Acting NSW chief veterinary officer, Therese Wright, said most producers in the zone “would not be impacted at all”.
She said it was believed to be a non-clinical case, and added that the alert was evidence biosecurity checks and measures were working.
“We’re simply being very up front – making sure export markets have confidence in our cattle,” Dr Wright said.
“Some (producers) we may contact to see if we can collect some samples. If they’ve got suitable home-bred cattle, we’d appreciate their co-operation.
“If they do rely on selling their animals for export we'd suggest they talk to their LLS district vet or NSW NAMP coordinator at the Elizabeth Macarthur Agricultural Institute.”
The transmission zone extends into NSW, with cattle in the zone unable to be exported to countries requiring at BTV-free status.
Tests on the 12-month-old dairy heifers in question at Echuca have not detected active bluetongue virus so far.
Victoria was previously BTV-free, while only parts of Northern NSW were included in a transmission zone.
It is unlikely the zone will be revoked before the 30 days is up.
The NSW Department of Primary Industries said additional surveillance will be conducted on herds in both Victoria and NSW as a precautionary measure.
“It is important to note that antibodies can be present in animals which have previously lived in an area exposed to the virus, or can be acquired through milk from a mother which has previously lived in an exposed area,” a spokeswoman said.
Affected farmers may still be able to export their stock if the animals test negative to blue tongue virus and live in a blue tongue virus free area for six months.
There are no changes to conditions for moving cattle from this temporary zone to other parts of Australia.
Bluetongue virus is a notifiable disease that does not affect people. It is spread by flying insects (midges) and can’t be eradicated from Australia.
Cattle are the most commonly infected ruminant, however sheep, goats, buffalo, camelids and deer are susceptible to BTV infection.
Agriculture Victoria says there has been no evidence of clinical disease in Australian livestock species to date, however the different BTV serotypes can cause varying severity of clinical disease in ruminants as seen in some overseas countries.
Symptoms in livestock may include fever, swelling of the lips and face, salivation and nasal discharge.
Ulcers may develop on the gums, cheek and tongue five to eight days after the onset of fever.