Sap of horses: epizootology and symptoms, methods of treatment and prevention

Horses, donkeys, mules and other animals belonging to the order of equids are subject to severe infectious diseases. Sap is a disease that is caused by gram-negative bacteria and is transmitted from infected animals to he althy animals and people. The risk of death after glanders is diagnosed in horses is high. Today, the disease is most often registered in Asian countries.

Description of the disease and its historical background

Infection was described in detail in the second half of the 19th century. Loeffler isolated a pathogenic bacterium from the contents of skin formations on the croup of an animal.A few years later, Russian veterinarians created a technique for diagnosing glanders in horses, which made it possible to start an anti-sap fight. Veterinarians have developed a test for the introduction of mallein. This method remains the most informative so far.

An outbreak of the disease in Russia was observed in the period from 1917 to 1924. The horse at that time was a valuable working unit: it was in demand in the fields, and was also used to move between settlements. In addition, there was a separate category of army horses, without which soldiers could not do.

The government has developed a special action plan for the prevention and diagnosis of glanders. During this period, more than 100 thousand animals were destroyed. The complete elimination of glanders on the territory of Russia was achieved by 1940.

Pathogen

Infection is caused by the bacterium Burkholderia mallei, which belongs to the second pathogenicity group.The microorganism causes mass destruction of horses, so it was used as a biological weapon during the war of 1861 in America. This pathogen is able to infect horses and humans in a short time.

The causative agent is short sticks arranged in the form of bacilli connected in pairs. They do not have spores or capsules. During the period of existence, they remain absolutely motionless, but begin to grow when they enter the nutrient medium.

Physical and chemical properties of pathogens:

exist at temperatures from -10 to +55 °;
resistant to some antibiotics;
does not withstand prolonged treatment with disinfectants.

The bacterium, when it enters the nutrient medium, begins to grow. A dense, brown-brown coating forms on the infected surface.If the pathogen enters the water or soil, then its properties can persist for 2 months. Inside the corpse of an animal, in its excrement, the bacterium exists from 2 to 3 weeks.

Help! The bacterium dies under the influence of UV radiation, does not withstand heating to temperatures above +80 °.

Symptoms and course of glanders in horses

Epizootology, or mass spread, begins with contact with an infected animal. Affected horses excrete the pathogen with secretions from the nostrils. It is also found in saliva and in the contents of skin formations over the entire surface of the croup. This means that a he althy horse can be infected by contact with a sick horse through the skin. If the pathogen comes into contact with a microtrauma on the rump of a he althy horse, then infection occurs much faster than if it enters through the sinuses and respiratory tract.

Particularly dangerous are individuals with chronic glanders. In the absence of visible signs of illness, they spread the pathogen around them by dispelling salivary or nasal secretions. Such horses can infect a he althy horse with short contact and cause epizootology.

In addition, transmission occurs during the exchange of horse equipment, during the reception of feed or through manure.

The factor that provokes infection is keeping animals in cramped stables. But during pasture pastures, the transmission of the pathogen slows down significantly. This is due to the high resistance of horses to glanders during grazing and the low ability of the pathogen to spread when exposed to direct sunlight.

After infection, the incubation period begins. It lasts from 3 days to 2 weeks. Then the symptoms appear, they determine the type of course of the disease:

Acute course.It is characterized by a significant increase in body temperature (up to 40-41 °), hyperemia of the mucous membranes. The horse begins to breathe intermittently, becomes weak, lethargic. On the second day, nodules with a red rim appear on the mucous membrane of the nostrils, they quickly merge, forming a continuous strip. The rash begins to undergo necrosis, ulcers with purulent contents form. At the same time, skin lesions develop on the inside of the thigh, in the neck. The last symptom is elephantiasis, or significant enlargement of the limbs.
Chronic course. In a chronic disease, the horse periodically rises in body temperature, coughing is observed. Animals lose weight. On the mucous membrane of the nostrils, wounds begin to appear, which then heal. Chronic glanders can last for several months or several years. It is detected during a thorough examination, but is almost never diagnosed during a superficial examination without taking biological material and clinical examination.
Latent flow. This is a life-long type of disease that can turn into an acute condition when the conditions for keeping the horse worsen. Latent glanders are almost impossible to diagnose without detecting signs of an acute course.

Diagnostic Methods

Among the methods for detecting glanders, the most informative is the allergic method. It includes 2 types of sampling of biological material:

Ophthalmic test. Mallein is placed in the conjunctival sac and the reaction is observed. After 2-3 hours, with a positive reaction, lacrimation begins, the release of pus. If the diagnosis is negative, then there is a slight reddening of the eye.
Subcutaneous test. It is carried out if the horse is diagnosed with eye diseases. A maleic injection is injected under the skin. After 6-8 hours read the reaction. If swelling appears at the injection site, body temperature rises (up to 39-40 °), then the test is considered positive.A negative reaction suggests no swelling or fever.

With positive samples, bacteriological studies are carried out. The diagnosis is made subject to the presence of three components:

detection of changes in internal organs that are characteristic of glanders;
isolation of a pathogen from biological material;
external signs of glanders.

Treatment

Horses suspected of having glanders are kept in quarantine. Until the diagnosis is made, animals are administered antibiotics of the penicillin or streptomycin group. At the same time, injections are made with vitamins and compounds to improve blood quality.

Attention! To prevent infection, horses with a confirmed diagnosis are taken away for slaughter. Animal corpses are burned without being opened.

Prevention and elimination

The country is allowed to import horses that meet sanitary veterinary standards. Once imported, horses are quarantined, where they undergo various diagnostic checks and are also tested for glanders. To prevent infections, measures have been introduced to comply with the mandatory preventive vaccination plan for horses.

If the maleic test gave a positive result, then the measures predetermined by the protocol for the destruction of the individual and the treatment of the premises are carried out:

the corpse is burned completely away from residential premises or agricultural facilities;
together with the corpse, bedding, manure and leftover feed are burned;
the soil after burning is treated with formalin or bleach solution;
the walls of the premises in which the horse was kept are treated with a solution of bleach 20%;
after disinfection, the walls are whitewashed with slaked lime.

The clothes and shoes of the personnel who worked with infected horses are treated separately. Protective suits are boiled for 15-20 minutes in a 2% soda solution. Gloves, hats, aprons are left for 20 minutes in a solution of chloramine.

Boots, galoshes are treated with a solution of chloramine. Personal clothes are kept in a steam-formalin chamber for 10-15 minutes. Transport, which was near the source of infection, is additionally treated with a 1- or 3% solution of chloramine.