Cases of Bovine Ephemeral Fever, also known as three-day sickness, are being seen in cattle on the NSW North Coast.
The disease has been confirmed via laboratory testing in herds across the northern rivers and far north coast. It is expected that the disease will move south as the season progresses.
Three-day sickness is an insect transmitted virus of cattle that causes a high fever and pain in the muscles and joints. On the North Coast it is usually seen in cattle between 6 months and 2 years of age, however if they are from outside the region adult cattle can also experience the disease.
Affected cattle are often by themselves, off their feed, seek shade and water, shiver, drool and are lame. Signs usually last only a few days and most cattle recover uneventfully.
Some cattle – especially bulls and heavier conditioned cattle – may go down and take several days to get back on their feet. Heavier cattle are at an increased risk of secondary complications as a result of being down. Pregnant cows may abort and bulls may become infertile for up to six months. Milk production can drop significantly in lactating cows.
The virus appears on the North Coast in summer as the population of the biting insects that transmit it increase. The occurrence of the disease is likely to increase following the recent rainfall in the region, providing favourable conditions for the insect populations to increase rapidly.
Producers are encouraged to seek veterinary advice and medication is highly effective in bringing down the fever and reducing the muscle and joint pain. Recovery tends to be quicker with less weight loss. There are several other diseases that may resemble three-day sickness requiring alternative treatment, so veterinary diagnosis is essential.
A paddock with plenty of shade, water and feed and free of steep gullies is ideal for cattle to recover in. Any affected cattle should be provided with shade, water and feed and turned or lifted twice daily to help prevent secondary complications.
Recently recovered cattle should not be sent to the abattoirs for several weeks, to give the body a chance to heal and avoid the possibility of downgrades from any residual muscle damage. Where treatments have been given any withholding periods must be observed.
A vaccine is available and its use is recommended for bulls and any cattle introduced from areas which do not normally experience the virus. In those areas where the virus is already active the vaccine is unlikely to provide protection, though in more southern areas there may still be time for the vaccine to provide protection before the virus arrives.
For further advice contact your North Coast Local Land Services District Veterinarian or private veterinary practitioner.