One of the most unpleasant diseases in cattle is hypodermatosis. For animal life, this ailment is usually not particularly dangerous. However, cows with hypodermatosis usually decrease significantly in productivity. In addition, this ailment is contagious. Therefore, animals suffering from hypodermatosis should be treated as quickly as possible.
What ailment
Bovine hypodermatosis is called a disease caused by the larvae of two types of subcutaneous gadfly: N. Lineatum (esophagus) and Hypoderma bovis (string). Both of these parasites behave almost identically in the body of cows and bulls. The only larva of H. Lineatum is usually localized in the submucosal layer of the esophagus, and Hypoderma bovis in the spinal canal.
Of farm animals, only cows are infected with such parasites. Hypodermatosis can also be affected by yaks, bisons, buffaloes, and zebu.
How does infection happen?
Hypodermic fly flies of both varieties attack cattle, usually in September - November on pastures. When attacking such insects, cows experience very severe pain. To determine the attack of subcutaneous gadfly is quite simple. The attacked animals lift their tails and try to escape from the pasture.
Having bitten 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 them on the body of an animal up to 500-800 pcs.
After about a week, larvae of the first age hatch from eggs laid by gadflies. The parasites that were born immediately begin to migrate, making moves in the tissues of the animal into the esophagus or spinal cord.
First stage of development
In the main habitat, larvae of the first age subsequently 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, parasites make fistulas in the skin of the animal.
After this, the larvae go into the third stage of development: crawl out, fall to the ground, dig into it a few centimeters and pupate. By autumn, adult gadflies fly out of the soil and again begin to attack the grazing cattle.
The main symptoms of cattle hypodermatosis
In the fall, immediately after the larvae begin to invade under the skin, the cows experience severe itching and swelling. In the future, these symptoms disappear. It is quite difficult to determine the presence of larvae of the first stage in the body of an animal. Such parasites are still small in size and emit not too many toxins. The only thing, the animal may experience soreness of 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, by-pass nodules begin to form on the body of infected animals. First, dense tubercles with a diameter of about 5 mm with a hole in the center or side appear under the skin of the animal. Infected cattle can lose weight, look weak and lethargic.
After 3 weeks, the nodules become visible to the naked eye. Holes in the tubercles for this period increase to 3-5 mm. Over time, as the larva grows, serous fluid begins to be released from the fistula .
Nodules are localized on the body of a sick animal, usually on the back, croup, and thighs. Sometimes they can also be seen on the neck, chest, or tail of a cow.
Diagnostics
If there is a suspicion of the presence of subcutaneous gadfly larvae in the animal’s body, specialists first of all conduct a visual inspection. The diagnosis of cattle hypodermatosis is made in most cases after palpation of the nodules of the back, croup and legs of cows and gobies. Cattle are examined for parasites in the northern regions of the country, usually in February, and in the southern regions in December.
What nodules look like with this disease can be seen in the photo below. Cattle hypodermatosis at the final stage of development of the parasite is diagnosed very easily. No laboratory tests to determine it by veterinarians at this stage are usually conducted.
Early cattle hypodermatosis is diagnosed in October - November. During this period, the disease is detected through indirect hemagglutination using serum.
Treatment
The therapy of cattle with hypodermatosis is aimed, of course, first of all at the destruction of larvae in the animal’s body. Significant symptoms of this disease in the initial stages occur with the introduction of parasites under the skin in the fall. Cows with itching and swelling in the fall are treated with systemic insecticides. Most often, Chlorophos is used for this purpose.
Such a tool is watered in a thin stream along the ridge of infected animals. In this case, use a special syringe. Dosages during processing use the following:
In most cases, farms carry out autumn processing not only of cows with swelling and itching, but also of apparently healthy ones. For prevention, in this case, "Chlorophos" is used in the same doses.
Another treatment of cows with insecticides is carried out in 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", for the treatment of cattle hypodermatosis can be used such means:
"Gzavon-2" (150 ml per animal weighing from 200 kg and 100 ml - up to 200 kg).
"Aversect-2" (0.5 ml / kg of weight).
An aqueous solution of Butox (up to 250 ml per ridge).
Also, insecticides such as Dioxafos, Cypermethrin, Dektomax, etc. are often used to treat this parasitic disease.
Safety precautions
Cure sick cows with insecticides, of course, should be careful. Such drugs are toxic to humans. Treatment of cattle infected with agents of this variety should be carried out with gloves, long-sleeved clothing and gauze bandages.
If there are signs of intoxication such as nausea, dizziness, vomiting, a farm employee should immediately stop all processing of animals and consult a doctor.
Cattle Hypodermatosis Prevention
Animals infected with a subcutaneous gadfly can lose in productivity significantly. For a year, farmers receive about 200 liters of milk from a sick cow alone. The weight loss of infected calves can reach up to 18 kg per individual.
The productivity of cows, calves and gobies with hypodermatosis decreases, mainly due to intoxication of their body with parasite metabolism products. Making moves in the tissues, the larvae of subcutaneous gadflies secrete a special dissolving fluid. Toxic, of course, are the excrement of these parasites.
In order not to incur losses due to hypodermatosis, farmers without fail carry out preventive measures at the farm aimed at preventing the development of this disease.
In order to prevent infection, in addition to watering the ridge of animals with insecticides in autumn, the following are practiced:
cows are treated with special sprays from April to September before pasture to the pasture every 10 days;
during the period of mass departure of gadflies, animals are driven out to pasture only in the evening-night time.
Often the cause of cattle hypodermatosis is also the crowding of cows on the farm. Therefore, in order to prevent the epidemics of this disease, as well as any other parasitic diseases, the technology of keeping cattle should be strictly observed. The cow shed should be spacious enough, well ventilated and dry.
To prevent the transfer of eggs or larvae from personal households, farm workers provide overalls and personal hygiene products. Newly acquired animals for the prevention of cattle hypodermatosis are pre-quarantined for 30 days.
What rules should be followed without fail
Slaughtering cows for meat is allowed no earlier than 2 weeks after treatment with insecticides. The carcasses of infected animals can only be sold for sale after thorough research for the presence of toxins in the tissues. When infected animals are detected on the farm, quarantine is officially declared with all the ensuing consequences.