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  1. RINGWORM WHAT IS IT? Ringworm is a common superficial fungal skin disease of all animals. The main economic effects of ringworm are on the showing and/or sale of affected animals due to its unsightly nature. It also causes significant damage of hides resulting in downgraded leather. It is a ZOONOSIS (i.e can be transmitted from cattle to man) and so personal hygiene is imperative after handling affected animals. SYMPTOMS Occurs mainly in calves around 2 – 8 months of age, although can occasionally be present in adult cattle. Ringworm can occur all year round, but is seen more frequently in housed cattle during autumn and winter. Housing and intensive management increases the spread as cattle are in close contact. The incubation period is 1 – 4 weeks. It is usually present as raised, grey/white circular lesions that range in size from 1 – 5cm, with a number of different patches present. The hair is missing, although the disease is not usually itchy. These lesions occur most commonly around the eyes, head, muzzle, neck and trunk. Ringworm is a self-limiting disease, and lesions will get better after 1 - 3 months in most circumstances. Chronically ill or poor-doers are likely to be worst affected, and take longer to recover. WHAT CAUSES IT? Ringworm is a fungal infection typically of Trichophyton species. The fungus can be spread by DIRECT animal to animal contact (eg. buying in infected stock) or INDIRECT (eg. infected housing especially wooden pens). The fungus can survive off the animal in the environment for years. DIAGNOSIS Your vet can take samples of the skin and/or hair from affected animals to diagnose ringworm. However in most cases, the appearance of the ringworm lesions is diagnostic. TREATMENT OPTIONS Do nothing, as ringworm is self-limiting disease and will resolve in most circumstances. However these animals remain infectious, and so will pass the ringworm onto other animals in the group. Topical antifungal washes are available (eg eniconazole, Imaverol™; natamycin, Mycophyt™). Follow manufacturer’s advice on the datasheet, but typical recommendations for Imaverol™ are to apply diluted solution 3-4 times a day at three day intervals until cure BUT labour intensive. Most useful for individual show animals or small group treatment. Vaccination against the main strain of ringworm (Trichophyton verrucosum) is possible using Bovilis Ringvac™. The vaccine can be used both as a preventative measure (before signs appear) or treatment using a double dose of vaccine (for animals already affected). The vaccination course is two intramuscular injections 10 – 14 days apart. Calves can be vaccinated from 2 weeks of age, and the vaccine should be protective three weeks after the second injection. PREVENTION Disinfection of housing should be practised to try to avoid/limit future outbreaks. Disinfection is difficult but not impossible. Isolate and treated any infected stock to limit the spread of infection within the group. You need to keep a careful eye on the group as the incubation period is up to 4 weeks. Use of an all-in all-out system will also help limit spread of disease between groups. If you have any suspect cases, you should seek advice from your vet as soon as possible. Dairy Herd Health & Productivity Service (DHHPS) Update Dec 2010 Telephone 0131 651 7474; e-mail dhhps@ed.ac.uk; www.ed.ac.uk/vet/dhhps