Anthrax disease in cattle

Anthrax is an infectious disease that affects almost all domestic and wild animals. It is dangerous because it spreads extremely quickly and most often leads to death. In addition, anthrax is transmitted to cattle not only from other individuals. The source of the disease can be any other animal, its body, and even the soil in which the pathogen can live for many years.

anthrax

Historical background

The word “Siberian” in the description of the disease appeared around the 18th century. It was at this time that a large-scale epidemic of the disease began in Siberia, which first spread widely among the polar deer. In the future, the infection nevertheless got into farms, which caused widespread devastation and mass deaths among domestic animals.

But it is worth noting that the disease, which is very similar to anthrax in terms of a set of symptoms, also occurred in earlier periods of history. The first written mention of it dates back to 600 BC. In the future, such scientists as Hippocrates and Celsius were engaged in describing such an ailment and the alleged methods of dealing with it. In the records of ancient doctors from Persia, the disease was also described. It was called “Persian fire”. There are certain references to anthrax even in Homer’s Iliad.

In European countries, the oldest record of the epidemic of this disease was made in the 820s. Since that time, large-scale distribution has been observed several times. Quite often, the territory of Russia was also subjected to the harmful influence of the disease.

Of course, the spread of such a dangerous disease prompted many domestic and foreign scientists to study it. The first effective research in this direction was carried out by two Russian doctors A. Eshke and N. Nozhevshchikov in the 18th century, when the epidemic in Siberia had almost reached its peak. A little later, in the works of S. Andrievsky, the name “anthrax” was first mentioned. Prior to this, the name anthrax was more popular in foreign scientific literature. The same researcher proved that the disease can be transmitted from animals to humans.

The famous French scientist R. Koch in 1876 advanced much further in his scientific work. He managed to create suitable conditions for breeding a pure culture of the pathogen, which made it possible to study in detail the main properties of the bacillus. Based on the achievements of Koch, A. Askoli developed the first methods for diagnosing a disease in patients. In 1881, L. Pasteur first developed a vaccine against anthrax. And, finally, in the 1940s, Soviet scientists prepared a new version of vaccination, which was widely used in the USSR.

A new option for vaccination

A new option for vaccination

Causes of appearance

The causative agent of anthrax is Baccillus anthracis, a spore-forming aerobic bacillus whose length does not exceed 10 microns. It actively develops in the tissues and blood of living organisms. In the temperature range of 12-42 degrees and in the presence of air, it begins to release spores.

It is worth noting that spores, unlike a full-fledged stick, are more resistant to external negative influences. A developed bacterium dies in direct sunlight in a few hours, when heated to 60 degrees, the pathogen is eliminated in 15 minutes. In frost (up to -15 degrees), the stick lives for another 24 days, and in animal corpses for more than 7 days. In water, the developed pathogen is able to stay active for several months.

As for the spores, they are not affected by low temperature. When boiled, they die only after a few hours. In the soil, the spore can live for decades, in water for several years. Caustic alkali and 1-5 formalin solution kills the spore form within 2-3 hours.

As for the ways the pathogen enters the body of a healthy animal, there can be several of them:

  1. Through food or water in which an anthrax bacillus is already present.
  2. When a cow comes into contact with the manure of a sick animal. In this case, the bacillus can enter the body through microtrauma and open wounds on the skin, damage to the mucous membrane.
  3. The pathogen can be carried by flies. The bacterium enters their body from the blood of infected animals or carrion.
  4. Through the items and tools for care that were used in working with a sick cow.

During periods of major epidemics, burning the corpses of cattle after death was rarely practiced. Most often they were buried in special burial grounds. But, in such burials, under favorable conditions, foci of anthrax can exist for decades. Spores in the soil germinate and may form new spores. As a result, if in the process of natural erosion or in the process of construction, reclamation work, the top layer of soil is removed, the disease comes out again and begins to spread.

Burning corpses of cattle after death

Burning corpses of cattle after death

In addition, infection is also possible in the case of grazing on pastures located above burial grounds. The spores, along with grass and plant seeds, come to the surface, where they are eaten by cows and other animals.

A more active spread of anthrax can be traced in spring and summer, when herds are often on pastures. But even in winter, cases of infection were observed. During the cold period, the bacillus enters the body of a cow, mainly with hay or bone meal (the bacterium does not die during the processing of meat industry products).

Forms of the disease

Despite the fact that the only causative agent of the disease is the bacillus Bacillus anthracis, the disease can manifest itself in several forms. So, depending on the nature of the lesion, there are:

  1. carbuncle form.
  2. septic variety.

Carbunculous anthrax

The cutaneous form can be traced in approximately 90% of cases of the disease. It can develop in places where the body is affected by the pathogen, or act as a secondary factor in the acute and septic course of the disease. Swellings appear on the affected areas of the skin, which, on palpation, are felt hard and hot. The animal feels a sharp pain when touched.

After a short period of time, the temperature on the swollen areas of the skin drops below normal, and the pain in the cow disappears. In this case, the tissues at the site of the lesion, starting from the center, die off, and in their place a round ulcer (carbuncle) of black color is formed. At the same time, the overall body temperature of cattle increases slightly.

Reference. Most often, carbuncles form on the head, abdomen, or neck of a cow. Sometimes there are ulcers on the lips, cheeks, palate and in the oral cavity.

septic form

This kind of course of the disease involves a rapid increase in body temperature to 40 degrees or more. By this time, the bacillus has usually spread through the bloodstream throughout the body. The animal shows signs of pneumonia, develops hemorrhagic pulmonary edema, inflammation of the brain, peritonitis, intestinal bleeding. With this form of the disease, the cow dies already within 1-3 days from the onset of the disease.

The death of a cow from the disease occurs in three days

The death of a cow from the disease occurs in three days

In addition to the two main ones, other forms of anthrax are also conditionally distinguished, which are determined by the specific location of the lesion. Among them, the most common:

  1. Respiratory. The animal shows symptoms of acute pneumonia, which develops into pulmonary edema.
  2. Anginal. Assumes a kind of latent form of the disease. Body temperature practically does not change, all signs point to a sore throat. The animal swallows food with difficulty, coughs, wheezing is heard when listening to the respiratory tract. With the development of the disease, the throat can become very swollen and block the supply of oxygen.
  3. Intestinal. Intestinal damage is accompanied by constipation, further liquid bloody stools and develops into intestinal paresis or peritonitis.

Symptoms

The incubation period when the bacillus enters the body is 1-2 days. Further, the pathogen begins to actively develop. In this case, anthrax can have a fulminant, acute and subacute course.

lightning current

This form of anthrax develops suddenly and kills cattle in minutes. It is almost impossible to detect the disease in a timely manner and take action. With this form, you can trace:

  • The rapid rise in temperature to 41 degrees or more.
  • A sharp attack of excitement in the animal, which also abruptly turns into complete apathy to everything that happens.
  • Pulse and respiration are greatly accelerated. The cow is breathing extremely heavily.
  • The mucous membranes acquire a bluish tint.

As a result, the animal simply falls to the ground and dies in convulsions. After death, blood foam may appear in the area of ​​​​the nostrils and in the corners of the mouth.

Acute form

This course of the disease develops more measuredly. Symptoms can be identified and treatment attempted. The main clinical signs of acute anthrax include:

Temperature rise to 42 degrees

Temperature rise to 42 degrees

  • increased breathing, as well as a more intense heartbeat;
  • temperature rise up to 42 degrees;
  • swelling of the scar;
  • a sharp decrease in appetite, up to the complete refusal of the cow from food;
  • cessation of milk formation in the mammary gland;
  • with the development of the disease, bloody stools and signs of blood in the urine are traced;
  • mucous membranes turn blue and spot lesions can develop on them;
  • the throat or abdomen may become very swollen.

Death in convulsions occurs in 2-3 days.

Subacute anthrax

In fact, it suggests the same symptoms as in the first two cases. The only difference is that death occurs 6-8 days after infection. In addition, the symptoms may periodically recede, which creates the illusion of recovery.

Diagnostics

Diagnosis of anthrax is carried out in a complex manner. First of all, pay attention to clinical symptoms. The most pronounced among them is the presence of carbuncles. Also, as a basis for suspicion, one can take a sharp loss of livestock after grazing on a new pasture near recently opened construction sites or after a heavy rainfall, landslide.

At the slightest doubt, you should immediately contact the veterinary service. In this case, a laboratory study is necessary. As a sample, the blood of a sick or killed animal is taken for it, from which the pathogen is isolated and a pure culture is grown in a nutrient medium.

If skin samples of a dead cow are available, a study is carried out based on the precipitation reaction. In this case, the bacillus can be detected even if it is not visible under microscopic examination.

An effective method is also the introduction of an allergen into certain areas of the skin of a cow. If the reaction can be traced, then the pathogen is present in the animal. In such cases, the farm is closed and quarantine is established on it, as well as the entire surrounding territory.

Treatment

Given the fact that the animal dies in the shortest possible time after development, it is immediately isolated from the main herd and treated. The main treatment course involves subcutaneous or intravenous (depending on the form) administration of a special anti-anthrax serum in combination with antibiotics. Among them, the most effective are penicillin and streptomycin, which are used in combination with tetracycline. Serum in some cases is replaced with gamoglobulin, which is more effective.

Injections for the treatment of cattle

Injections for the treatment of cattle

Before use, the drug is heated to a temperature of 38 degrees. The average dose is 100 to 200 ml. At the same time, to prevent an acute reaction to the drug, 1 ml of serum is first injected subcutaneously. 20-30 minutes after the first injection, the second one is administered. It should be noted that if within 12 hours the temperature and general condition of the cow remains unchanged, the animal is given a second dose of the drug.

Antibiotics are applied every 4 hours three times a day. The agent is no longer injected subcutaneously, but into the muscle tissue. If, during visual examination, pronounced external areas of the lesion stand out, injections are carried out in the immediate vicinity of them. Such external manifestations may be carbuncles or swelling of the throat. Antibiotic treatment is carried out for 7-10 days, after which they are administered for another 5 days for prophylaxis.

Prevention

All preventive measures in the fight against anthrax are as follows:

  • Regular vaccination of animals in industrial and private farms. It is especially important for cattle that are bred in areas where the disease was previously traced, or if a new animal was brought from such an area. In the future, with the expansion of the livestock at the expense of young animals, they are re-vaccinated.
  • Identification, accounting and elimination of foci of infection in soil layers.
  • Periodic veterinary checks, as well as the study of meat and dairy products for the presence of a pathogen.
  • Periodic disinfection of premises, paddocks, barnyards with sodium hydroxide and other disinfectant solutions.
  • To prevent the spread of the disease in the herd, the carcasses of animals after the death, as well as manure, bedding and other materials, are immediately burned.
  • The soil in the places of livestock death, as well as under the floor in the barn, must be treated with a solution of caustic soda or formaldehyde. In this case, the solution is heated to a hot state.

Attention! If the anthrax pathogen is detected in an animal on the farm, in addition to it, quarantine is also imposed on the settlement, surrounding pastures, all local enterprises for the processing of meat, dairy and by-products.

Conclusion

Anthrax can cause extreme devastation in the region’s agriculture. That is why, at the first suspicions, it is necessary to contact the district veterinary service and immediately take measures to prevent the spread of the disease. In addition, special attention should be paid to preventive measures that will help protect the farm from infection.

Anna Evans

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