Hypodermatosis in cattle: causes, symptoms, diagnosis and treatment

2024 Author: Howard Calhoun | [email protected]. Last modified: 2023-12-17 10:16

One of the most unpleasant diseases of cattle is hypodermatosis. For the life of animals, this disease usually does not pose a particular danger. However, cows with hypodermatosis are usually significantly reduced in productivity. In addition, this disease is contagious. Therefore, animals with hypodermatosis should be treated as soon as possible.

What a sickness

Cattle hypodermatosis is a disease caused by the larvae of two types of subcutaneous gadflies: H. Lineatum (esophagus) and Hypoderma bovis (line). Both of these parasites behave in the body of cows and bulls in almost the same way. The only thing is that H. Lineatum larvae are usually localized in the submucosal layer of the esophagus, and Hypoderma bovis - in the spinal canal.

From farm animals only cows become infected with such parasites. Hypodermatosis can also affect yaks, bison, buffaloes, zebu.

How is it happeningcontagion

The subcutaneous gadfly flies of both varieties attack cattle usually in September - November on pastures. When attacked by such insects, cows experience very severe pain. Determining the attack of subcutaneous gadflies can be quite simple. Attacked animals lift their tails and try to run away from the pasture.

After biting a bull or a cow, the female gadfly of this species lays a huge number of eggs in the wound. Only one such fly can leave up to 500-800 of them on the body of an animal.

About a week later, the larvae of the first age hatch from the eggs laid by the gadflies. The parasites that are born immediately begin to migrate, making passages in the tissues of the animal into the esophagus or spinal cord.

The first stage of development

In the main habitat, the larvae of the first age continue to live and feed for about 5 months. Then they begin to migrate under the skin of the animal. Here the larvae form colonies and pass into the second stage of development. Next, the parasites make fistulas in the skin of the animal.

After that, the larvae pass into the third stage of development: they crawl out, fall to the ground, burrow into it a few centimeters and pupate. By autumn, adult gadflies fly out of the soil and again begin to attack grazing cattle.

Main symptoms of hypodermatosis in cattle

In autumn, right after the larvae begin to penetrate under the skin, cows experience severe itching and swelling. In the future, these symptoms disappear. Determine the presence in the body of the animal of the larvae of the firststages are difficult. Such parasites are still small in size and do not release too many toxins. The only thing is that the animal may experience pain in the migration sites of parasites during palpation.

The symptoms of hypodermatosis in cattle become much more pronounced after the larvae move under the skin. During this period, nodules begin to form on the body of infected animals. First, dense tubercles with a diameter of about 5 mm appear under the skin of the animal with a hole in the center or side. Infected cattle may lose weight, appear weak and lethargic.

After 3 weeks, the nodules become visible to the naked eye. The holes in the tubercles by this period increase to 3-5 mm. Over time, as the larva grows, serous fluid begins to flow from the fistula.

Nodules are localized on the body of a sick animal, usually on the back, croup and hips. Sometimes they can also be seen on the neck, chest or tail of a cow.

Diagnosis

If you suspect the presence of larvae of the subcutaneous gadfly in the body of an animal, specialists first of all conduct a visual inspection. The diagnosis of "hypodermatosis of cattle" is made in most cases after palpation of the nodules of the back, croup and legs of cows and bulls. Cattle are inspected for parasites in the northern regions of the country, usually in February, in the southern regions - in December.

How nodules look with this disease can be seen in the photo below. Hypodermatosis in cattlethe final stage of development of the parasite is diagnosed very easily. No laboratory tests are usually carried out to determine it by veterinarians at this stage.

Early hypodermatosis of cattle is diagnosed in October - November. During this period, the disease is detected through indirect hemagglutination using serum.

Treatment

Therapy of cattle with hypodermatosis is directed, of course, primarily to the destruction of larvae in the body of the animal. Significant symptoms of this disease in the initial stages are when parasites are introduced under the skin in the fall. Cows with itching and edema are treated with systemic insecticides in autumn. Most often, "Chlorophos" is used for this purpose.

This remedy is poured in a thin stream along the ridge of infected animals. In this case, a special syringe is used. Dosages for processing use the following:

• for cows weighing over 200 kg - 24 ml;
• with body weight up to 200 kg - 16 ml.

In most cases, farms carry out autumn processing not only of cows with edema and itching, but also of outwardly he althy ones. For prevention, Chlorophos is used in the same doses.

Another treatment of cows with insecticides is carried out in the spring, during the period of migration of larvae under the skin of animals. In this case, Chlorophos is also most often used. Such late treatments are carried out in the spring only for diseased cows.

What other drugs can be used

In addition to "Chlorophos", the following agents can be used to treat hypodermatosis in cattle:

• "Gzavon-2" (150 ml per animal weighing from 200 kg and 100 ml - up to 200 kg).
• "Aversekt-2" (0.5 ml/kg of weight).
• Butox aqueous solution (up to 250 ml per spine).

Also, insecticides such as Dioxafos, Cypermethrin, Dectomax, etc. are often used to treat this parasitic disease.

Safety

Treat sick cows with insecticides, of course, should be done carefully. Such drugs are toxic to humans. Treating infected cattle with this variety should be done with gloves, long-sleeved clothing and gauze bandages.

When signs of intoxication such as nausea, dizziness, vomiting appear, the farm employee should immediately stop all animal handling activities and consult a doctor.

Prevention of hypodermatosis in cattle

Animals infected with a subcutaneous gadfly can lose productivity significantly. For a year, farmers lose about 200 liters of milk from one sick cow alone. The weight loss of infected calves can reach up to 18 kg per individual.

The productivity of cows, calves and calves with hypodermatosis decreases, mainly due to intoxication of their body with metabolic products of parasites. Making moves in the tissues, the larvae of the subcutaneous gadflies secrete a special dissolving liquid. Toxic, of course.same, are the excrement of these parasites.

In order not to incur losses due to hypodermatosis, farmers must take preventive measures on the farm to prevent the development of this disease.

To prevent infection, in addition to watering the ridge of animals in autumn with insecticides, the following is practiced:

• cows are treated with special sprays from April to September before pasture every 10 days;
• during the mass departure of gadflies, animals are driven out to pasture only in the evening and at night.

Often the cause of hypodermatosis in cattle is the overcrowding of cows on the farm. Therefore, in order to prevent epidemics of this disease, like any other parasitic ones, it is necessary to strictly observe the technology of keeping cattle. The cow barn should be spacious enough, well ventilated and dry.

Working personnel of farms, in order to avoid the transfer of eggs or larvae from personal farms, are provided with overalls and personal hygiene products. Newly acquired animals for the prevention of hypodermatosis in cattle are previously kept in quarantine for 30 days.

Which rules must be observed without fail

Cows are allowed to be slaughtered for meat no earlier than 2 weeks after insecticide treatment. The carcasses of infected animals can be put on sale only after thorough research has been carried out on the subject ofthe presence of toxins in tissues. When infected animals are detected on the farm, quarantine is officially declared with all the ensuing consequences.