NSW farmers should be on the lookout for three-day sickness (Bovine Ephemeral fever - BEF) after the virus was detected around the Casino area.
North Coast-Hunter Local Land Services said the detection is earlier in the season than usual, normally arriving in the Mid North Coast around late summer.
Three-day sickness is an insect-transmitted virus of cattle that causes a high fever and pain in the muscles and joints.
North Coast Local Land Services district veterinarian Ian Poe, who is based in Kempsey, said the virus effects younger cattle, usually between six months and two years of age.
"It's a bit hit and miss," he said. "It's one of those things we do see regularly in the area, not necessarily every year so its probably been a few years since we've had a significant season with it."
"Once animals have been exposed to it they develop immunity and then they're pretty well immune for life.
"Usually what we see is it'll mostly affect young animals that haven't been exposed before...but if we miss a few years then maybe you start to get it in your two and three year olds."
Local Land Services said some cattle, especially bulls and heavier conditioned cattle may go down and take several days to get back on their feet, increasing the risk of secondary complications.
More severe lesions in the nerves of animals may result in some individuals being down or wobbly for prolonged periods.
Pregnant cows may abort and bulls may become infertile for up to six months. Milk production can drop significantly in lactating cows.
"It is something that you can vaccinate for so particularly if they've got heavier conditioned young maybe two year old heifers or three year olds that haven't been exposed it might be worth considering," Mr Poe said.
"The vast majority of animals recover so it doesn't have a high mortality rate."
Affected cattle should be provided with shade, water and feed and turned or lifted twice daily to help prevent secondary complications. A paddock free of steep hills or gullies is preferable.
Local Land Services said producers further south still have time to vaccinate to provide protection with dosage taken two to four weeks apart if previously unvaccinated and then a booster every 12 months.
For further advice contact your North Coast Local Land Services District Veterinarian by calling 1300 795 299 or private veterinary practitioner.
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