Contagious ecthyma of sheep: virus causative agent and symptoms, how to treat and prevent

Contagious ecthyma is a viral disease of sheep, in which abscesses, vesicles, papules and crusts form on the oral mucosa, skin of the lips, genitals and udder. Animals aged 1.5 to 3 months are most susceptible. The mortality rate of young animals is 90%, adults - 5-10%. In scabs at room temperature, the virus can survive up to 15 years.

Causes of disease

The causative agent of contagious ecthyma is an epitheliotropic virus belonging to the Poxviridae family. Under favorable conditions for it in the external environment, it persists for quite a long time - from 4 to 15 years.At high humidity and under the influence of high temperatures, it is quickly disinfected.

Carriers of the disease are ill or infected individuals. Their secretions enter the external environment, infecting bedding, drinkers, feeders, pastures. If the udder of the ewe has papules and vesicles, the lambs will be infected.

Ecthyma contagious outbreaks occur in young sheep when they are weaned and moved to other pastures. The total maintenance of he althy and infected animals leads to the fact that after 2-3 weeks from the moment of infection, the parapox virus infects the entire herd.

Signs and symptoms

Depending on the dose of the virus that has entered the animal's body, its immunity, the incubation period ranges from 4 to 8 days. In young sheep, ulcers and papules form:

• on the oral mucosa;
• on hairless scalp (nostrils, eyelids, cheeks);
• genitals.

First, red spots appear in the corners of the mouth and along the edges of the lips, inside which nodules form, turning into pustules and vesicles. After a while, they open, the integrity of the mucous membrane is violated. In place of abscesses, scabs and a dry crust of dark brown color are formed. Infected lambs develop a fever and have difficulty eating and drinking water. As a result of exhaustion, almost 90% of young animals die.

In animals whose course of the disease did not lead to death, after 10-14 days, crusts and scabs fall off, leaving almost no scars, sheep recover, acquiring resistance to the virus for 12-16 months.

If the virus has infected the lamb's hooves, they become sensitive, the animal limps. The genital form of the disease is characterized by the formation of ulcers and crusts on the inner surface of the thighs, on the foreskin of the penis, on the udder.The recovery period for individuals that have been re-infected is 40-50 days.

Diagnostic rules

Establish the fact of sheep disease help:

1. Clinical and laboratory tests of smears. Samples of scabs or purulent discharge are sent for research. If group or fractional colonies of dark red elongated bodies of the epithelotropic virus are found in them, the animal is infected.
2. Biological samples. They are carried out on clinically he althy individuals by rubbing liquid from scabs into the inner surface of the thigh of their skin. If lambs show classic symptoms 3-5 days after infection, this is contagious ecthyma.

When making a diagnosis, diseases such as mycotic dermatitis, necrobacteriosis, foot-and-mouth disease and smallpox should be excluded.

How to treat contagious ecthyma in sheep

Having found signs of parapox infection in sheep, they begin to treat it:

• the virus has reached the oral mucosa. Therapy involves treating the affected area with 1% potassium permanganate solution, 5% copper sulphate, 3% carbolic acid emulsion, 3% hydrogen peroxide;
• in case of damage to the skin, use a 10% solution of copper sulphate, salicylic or dibiomycin ointment, tincture of iodine.

If the sheep practically does not take food (severe course of the disease) - they are treated with the listed means or prescribe broad-spectrum antibiotics, coupled with biomycin.

Disease prevention

Measures to prevent the spread of the disease:

• separation of infected individuals from the general herd;
• carrying out preventive measures in the external environment to destroy the infectious agent;
• when buying sheep in other subsidiary farms, animals are quarantined for up to 30 days. During this period, they are examined for signs of the disease every week;
• maintenance of watering places, pastures and sheep farms in a condition corresponding to sanitary and veterinary standards;
• timely vaccination of animals, after which sheep become immune to the virus for 6-8 months;
• regular implementation of measures for the disinfection of inventory, equipment, work shoes and clothing, buildings and the surrounding area.

Grazing cattle on pastures where sick animals were kept is not recommended for 2 years.

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