Cattle pasteurellosis: symptoms and treatment. Pasteurellosis

Igor Nikolaev

Reading time: 3 minutes

A A

Pasteurellosis in large cattle are often diagnosed in the agricultural sectors of all countries. An infectious contagious disease affects many organs of the animal. It causes enormous damage to large farms and farmers. It consists not only in forced treatment, but also in the death of cows. In this article we will look at what signs can be used to distinguish the disease and whether there is a chance of recovery.

Description of cattle disease

The infection enters the body very quickly. IN in rare cases death occurs within 24 hours. Pasteurellosis affects most domestic and wild animals. The causative agent is considered to be short oval rods that cannot move. They take over the lungs. However, symptoms do not appear immediately, so treatment is delayed.

Diseases are susceptible to all ages, but the most swipe applied to calves. Young individuals are more susceptible to the rod.

They can be infected by both sick animals and healthy animals that carry bacteria that live permanently on the mucous membrane. respiratory tract.

Once the immune system is weakened as a result of poor cattle management, non-compliance with the rules of disinfection, walking, poor-quality feeding, pasteurellosis begins to develop. Its favorite places are mucous membranes and injuries.

The bacteria themselves easily die even under the rays of the sun. But they are easily transmitted in the following simple ways:

cough and sneezing;
feces and urine;
blood and milk.

All these sources are carriers of infection. If they or their traces are found indoors, get into the air, onto clothes or tools, food or equipment, then it becomes very easy to catch the disease. They can be carried by rodents, insects and animals. Most often, the disease is detected in the second half of summer and autumn.

Symptoms of pasteurellosis

It only takes a few hours for the bacteria to spread throughout the body. In rare cases, the infection period increases to three days. It can manifest itself in four forms, hence the corresponding signs of the disease in cattle.

Symptoms of pasteurellosis:

hyperacute noted sharp increase temperature by one or two degrees. Cardiovascular system It doesn't work smoothly and glitches. There may be bloody diarrhea. It is with this form that cows die in less than a day. Their hearts can't stand it and their lungs fail. Symptoms may not even have time to appear;
acute is expressed in diseases of the intestines or respiratory system. The animal's condition is weak and depressed, eating disorder occurs. Some parts of the body swell, body temperature rises, and toxicosis is noticeable. The nasal mucosa remains dry and icy. The cow stops giving milk and the cud disappears. First there is constipation, then bloody diarrhea. Blood also flows from the nose, as does urine. Death occurs in one or two days;
subacute is observed when the pathogen remains in the lungs, causing various inflammatory processes. This form is characterized by trembling and signs of fever;
chronic is considered the longest form. It is also divided into edematous, thoracic and intestinal types.

During the last course of pasteurellosis in cows, the same symptoms are noticed, but they are not so pronounced. The disease selects the affected area and attacks with bacteria:

The spectacled appearance manifests itself in swelling of the area of the lower jaw, neck, abdomen and legs. If even the tongue and larynx swell, it becomes difficult for the animal to breathe and a lot of viscous saliva accumulates. The calves are clearly excited, the mucous membranes are saturated with blood. It can appear from the first days of life of the cubs. Death is confirmed in the first two days;
in the chest form of the disease, signs of pneumonia are diagnosed. The individual loses the ability to eat and loses appetite, and the rumen stops contracting. The cow breathes heavily and hoarsely, and begins to cough heavily. Foam may come from the nose. Death occurs in a week or a little less;
intestinal type is expressed in anemia syndrome. The lungs suffer slightly, and there is even a desire to eat food. But the condition is weak, the intestinal tract is affected.

All variants of the development of pasteurellosis are characterized by the presence of diarrhea. Therefore, in the body of a sick animal, dehydration, extreme exhaustion and cessation of the functionality of one or another organ quickly occur.

Making a diagnosis

For staging accurate diagnosis and prescribing the correct treatment for pasteurellosis in cows, the symptoms are carefully studied and an examination is carried out. Obvious symptoms diseases indicate pathology in the animal’s body.

To carry out the analysis, a part of the spleen, liver, kidneys and lungs with lymph nodes is taken. All elements must be examined a maximum of five hours after death. This is done if you have not had time to start treatment and take medications.

If the animal does not die in a short period of time, blood is taken from the superficial vessels and mucus from the nasal passages. The final conclusion is made after a comprehensive examination.

A specialist needs to distinguish pasteurellosis from anthrax, which also affects cattle. It can be confused with salmonellosis, bronchial diseases and other infections that develop in the calf.

Treatment of pasteurellosis

First of all, treatment of pasteurellosis in cows should begin with quarantine. The sick individual is placed separately from its relatives. The barn should be warm, not damp, with a ventilation system.

If the disease occurs in chronic form, the animal may retain its appetite. In this case, the food should not be heavy. Food should be chosen that is nutritious, light, and liquid. Drug therapy is also used:

hyperimmune serum;
tetracycline antibiotics, long-acting;
sulfonamides ( antimicrobials) given with food;
glucose, sodium chloride solution are necessary to maintain the body.

Ways to fight

After an effective therapeutic complex technique, the animal receives immunity from pasteurellosis for about a year. Sometimes the period is reduced to six months depending on the conditions of detention and compliance with quarantine measures.

Vaccines and serums are sold against the disease and are widely used in agriculture.

They are aimed specifically at each type of animal that can become infected with pasteurellosis. If one individual is infected, the rest are injected with a special serum and observed, and their temperature is measured.

Cattle pasteurellosis is a dangerous infectious disease that literally leads to the death of a cow in just a few days. Besides, this disease also applies to most other domestic animals, birds and humans. Therefore, it is extremely important to know the main manifestations of this disease and take timely measures to neutralize it.

What is the disease?

Cattle pasteurellosis is a consequence of the development in the body pathogenic bacteria. As this disease progresses, the affected animal develops blood poisoning, pneumonia (including purulent pneumonia), endometritis, conjunctivitis and a number of other secondary diseases and complications.

The most susceptible to infection are cows, rabbits and poultry. The disease is also transmitted to many species of wild animals. It is widespread in almost all countries of the world. In Russia greatest number cases of infection are registered in the central regions of the country.

Causes and causative agent

Pasteurellosis is caused by bacteria of the genus Pasteurella. There are several types of such bacteria. Two of them are dangerous for cattle:

Pasteurella multicida.
Pasteurella hemolytica.

Both types of pathogens are characterized by fairly low resistance to external negative impacts. When exposed to sunlight, the bacterium dies within 10 minutes. The pathogen can live in manure or moist soil for 2 weeks. When exposed to temperatures of 80 degrees or higher, pasteurella dies within 5 minutes. Disinfectants that are destructive to infection are solutions of creolin, slaked lime, and caustic soda.

When ingested by a cow, the bacteria become established in the animal's respiratory tract and intestines. In this case, the spreaders of the disease are most often sick cattle and those individuals that have already been cured. In addition, the pathogen is also long time able to live in the body of healthy animals.

In external environment The bacterium enters with feces, blood, milk, saliva and urine of animals. Transfer can occur in the following ways:

with food and water;
through care items;
through the common litter;
by air;
along with mucus when sneezing or coughing;
through the ground;
in contact with wild animals or humans.

The infection can also be transmitted to healthy individuals through the bites of blood-sucking insects and rodents that have previously been in contact with sick livestock.

Most often, pasteurellosis develops in cows from mid-summer to late autumn. At this time, optimal conditions for the development of infection are observed. Young animals are more susceptible to infection.

Symptoms and course for different forms

Once it enters the body, the bacterium begins to develop extremely quickly. Damaging tissue, pasteurella spreads along with blood and lymph. At the same time, their waste products cause septicemia. The pathogen is also capable of damaging tissue capillaries, which leads to swelling throughout the body. After blood poisoning, death occurs within the next 3 days.

The incubation period for pasteurella in the body ranges from 5-6 hours to 3 days. After this, the disease manifests itself in acute, hyperacute, chronic and subacute forms. Each of them suggests its own clinical signs.

Acute

The acute course of pasteurellosis is accompanied by the following main manifestations:

general depression, accompanied by loss of appetite;
increased heart rate and breathing;
the temperature rises above 40 degrees;
cessation of milk production.

With further development of the acute course of the disease, it may manifest itself in various forms: thoracic, intestinal and edematous. At chest form the underlying disease is supplemented by pleuropneumonia. In this case, in addition to the main symptoms, the following clinical signs also appear:

purulent exudate is released from the nasal cavity;
breathing is very difficult;
severe diarrhea, in which after a certain time the amount of blood increases;
when listening to the lungs, friction sounds are heard from them;
may be accompanied by a strong dry cough.

In the intestinal form of pasteurellosis, the following clinical signs are observed:

refusal of food;
excessive thirst;
weakness and depression;
rapid weight loss;
blue discoloration of mucous membranes.

Most often, this manifestation of the disease is observed in young animals.

With edematous pasteurellosis, inflammation of the subcutaneous layer of tissue develops. This leads to severe swelling in the area of the udder, genitals, neck and other parts of the body. If this form of the disease develops, death occurs within 1-2 days. The edematous form is accompanied by the following symptoms:

cessation of milk production;
rapid breathing, while it is extremely difficult for the cow to breathe;
on different areas swelling occurs in the body;
Asphyxia may gradually develop, which leads to the death of livestock.

Subacute

In the case of a subacute course, the disease develops more slowly. It can last up to two weeks. At the same time, on initial stage symptoms are poorly developed and gradually become more pronounced. The main signs of this form of the disease include:

increased body temperature;
severe dry cough;
oppression and refusal of food;
increased thirst;
mucous discharge from the nasal cavity, which in a short time turns purulent;
the appearance of swelling in the neck and head;
conjunctivitis.

Reference. Based on subacute pasteurellosis, secondary diseases often develop, for example, enteritis.

Super acute

The hyperacute form of the disease is the most dangerous. From the end of the incubation period of the pathogen to the death of the cow, no more than 12 hours pass. Often no clinical signs appear at all. Therefore, it is extremely difficult to diagnose and treat this course of the disease.

If clinical signs are present, they manifest themselves as follows:

a sharp increase in the cow’s body temperature to 42 degrees;
severe swelling;
diarrhea with high content blood in feces.

Death occurs as a result of pulmonary edema or disruption of the cardiovascular system.

Chronic

The chronic form of the disease differs less severe symptoms and more long period development (up to 4-5 weeks). But despite this, it also often ends fatal. The symptoms in this case are as follows:

difficulty breathing;
rapid weight loss;
refusal of food;
swelling of the joints of the limbs;
severe diarrhea is possible.

Diagnostics

Since the disease has infectious nature and often leads to death, it timely diagnosis is a top priority. Detection of pasteurellosis in the body of cattle is carried out on the basis of clinical signs, laboratory and pathological studies.

For laboratory study use samples from dead or intentionally killed animals. Particles of the liver, lung, spleen, and lymph nodes are suitable for this purpose. Materials are taken no later than 5 hours from the moment of death of the livestock. The culture isolated from the resulting sample is placed in a nutrient medium and its membership in the Pasteurella genus is determined.

In pathoanatomical studies, a positive test result is established if following changes in organs and systems:

numerous hemorrhages in the lungs, intestines, respiratory tract, as well as on the pericardium and epicardium of the heart;
large accumulations of blood and lymph that form in the tissue under the skin;
increased in size lymph nodes;
Certain parts of the digestive tract and intestines are significantly inflamed and swollen.

Attention! It is extremely important to carry out a comprehensive analysis in order to distinguish pasteurellosis from piroplasmosis, anthrax and other diseases with similar clinical manifestations. Correct diagnosis of such a disease is the basis for its successful treatment.

Treatment

If characteristic signs of the disease are detected, the animal is immediately isolated from the rest of the herd. A warm, dry room with well-equipped ventilation is used as quarantine. At the same time, the cow is transferred to a special diet, carefully balanced in terms of vitamins, mineral composition and nutrients.

The entire further course involves exclusively drug treatment. It assumes a symptomatic and specific focus. In the first case, it is assumed that the functioning of the organs and systems of the body affected by the disease will improve. For this purpose, use:

painkillers;
antipyretics;
diuretics;
restorative medicines normal function digestive tract.

In parallel with the treatment of symptoms, the fight against developing infection. For this purpose, serum against pasteurellosis can be used. But it is worth noting that it is used only in the first stages of development of the acute form of the disease. With further progression of the disease, it becomes useless. The vaccine against bovine pasteurellosis is administered intravenously or intramuscularly in dosages determined by the veterinarian.

In addition to the main treatment, a number of antibiotics are also prescribed to help cope with inflammation and eliminate developing pasteurella. The main drugs of this type include:

levomecithin;
biomycin;
streptomycin.

Various sulfonamide drugs have a good effect. To support the body, livestock may be prescribed intravenous injections glucose. General course treatment lasts up to full recovery animal and is determined individually in each specific case.

Prevention

More effective measure the fight against pasteurellosis is a high-quality preventive activity:

ensuring proper sanitary conditions for keeping livestock large farms and in subsidiary farms;
proper balance of animal feeding. This also includes constant monitoring of feed quality;
purchasing new heads for the herd exclusively from farms that have been tested and are free from various infectious diseases;
quarantine of newly acquired animals for a period of at least 30 days for examination and vaccination;
providing personnel working on the farm with a set of work clothes, which they will use exclusively within their workplace;
periodic disinfection livestock premises, feeders and equipment with solutions of caustic soda, slaked lime or creolin.

To prevent mass infection of the entire herd, if an animal is suspected of having pasteurellosis, it is immediately isolated in a separate room. In this case, the breeder is obliged to contact a qualified veterinarian as soon as possible.

Attention! If cases of the disease have been registered on a farm, its herd is replenished exclusively with animals that have been vaccinated.

Conclusion

Pasteurellosis is a fairly common disease of livestock. It can lead to serious consequences and as soon as possible reduce the farm's population. That's why preventive measures To prevent it, breeders must pay attention special attention. In addition, if symptoms of the disease are detected, you should immediately seek professional help. Trying to solve the problem on your own can make the situation significantly worse.

Pasteurellosis (Latin, English - Pasteurellosis; hemorrhagic septicemia) - contagious infectious disease animals of many species, characterized by acute course septic phenomena, lobar inflammation lungs, pleurisy, edema in various areas body, and in subacute and chronic courses - purulent-necrotizing pneumonia, damage to the eyes, joints, mammary glands and hemorrhagic enteritis (see color insert).

Historical background, distribution, degree of danger and damage. The disease has been known for a long time, but its infectious nature was established in 1878 by E. M. Zemmer, Pirronchito and Rivogliata. The pathogen was first isolated by L. Pasteur in 1880. In the same year, L. Pasteur conducted the first experiments to weaken bacterial cultures isolated from dead chickens and immunized birds. In honor of his merits, this pathogen was named pasterella, and the disease it caused was named pasteurellosis.

The disease is widespread in all countries of the world. In our country, pasteurellosis is registered in all regions, but the highest incidence is observed in middle lane RF. Economic damage from pasteurellosis consists of losses from mortality, forced slaughter of sick animals and costs of carrying out preventive and health activities.

The causative agent of the disease. The causative agent of pasteurellosis - Pasteurella multocida - is a polymorphic, often short, gram-negative, immobile ellipsoidal rods, located separately, in pairs or, less often, in chains; they do not form spores; aerobes and facultative anaerobes. Smears from blood and organs are characterized by bipolar coloring, often with a pronounced capsule. On ordinary nutrient media they give good typical growth.

Antigenically, P. multocida is heterogeneous; it has 4 capsular serotypes (A, B, D, E) and 12 somatic types. Determination of the antigenic structure of P. multocida strains plays an important role in the selection of vaccine strains, in particular for the preparation of a vaccine against pasteurellosis in cattle - serotype B, birds - A and D and pigs - A, B, D.

Pathogenic and virulent properties of various serotypes of the pathogen various types animals vary widely.

In the occurrence of pasteurellosis among animals, especially in small and large livestock, hemolytic pasteurella (P. haemolytica), which has two biotypes: A and T, which is currently taxonomically included in the genus Actinobacillus, plays a certain role. To differentiate P. multocida from P. haemolytica, growth on MacConkey agar, white mouse resistance test and hemolysis on blood agar (positive for the latter) are used.

Pasteurella is stable in manure, blood, cold water for 2...3 weeks, in corpses for up to 4 months, in frozen meat for 1 year. Direct sun rays kill them within a few minutes, at a temperature of 70...90 "C they die within 5...10 minutes. Treatment with a 5% solution of carbolic acid neutralizes pasteurella after 1 minute, with a 3% solution - after 2 minutes , 5% solution of lime milk (calcium hydroxide) - after 4...5 minutes, 3% hot solution (50 ° C) of sodium bicarbonate and 1% solution of bleach - after 3 minutes.

Epizootology. All species of domestic mammals and birds are susceptible to pasteurellosis. Buffaloes, cattle, rabbits and chickens are most susceptible. Horses and carnivores have relatively high resistance to pasteurellosis. Pasteurellosis appears in the form of sporadic cases, but under conditions conducive to its spread, it can acquire the character of an epizootic.

The main source of the infectious agent is sick and recovered animals, as well as clinically healthy animals that were in close contact with patients with pasteurellosis. Great value in epizootology, the disease has pasteurellosis, which in disadvantaged farms reaches 70% among cattle, 50% in sheep, 45% in pigs, more than 50% in rabbits, and 35 to 50% among chickens.

Factors contributing to the epizootic spread of pasteurellosis include mass movements of animals without due consideration of the degree of welfare of farms due to pasteurellosis, the lack of proper organization of economic and veterinary-sanitary measures in livestock and poultry farms, and the widespread use of insufficiently neutralized slaughterhouse waste as feed.

The ways of excretion of pathogens from an infected body are different: with feces, urine, especially with discharge from the nose during coughing, snorting, with blood during bleeding. Sick cows can also excrete pasteurella in their milk.

The pathogen is transmitted through direct contact (keeping healthy and sick animals together), as well as through infected feed, water, soil, care items, milk, waste from the meat processing industry, mouse-like rodents, insects, wild birds and humans.

Infection of animals is possible through the respiratory system (aerogenous route), injured skin and mucous membranes.

Morbidity and mortality from pasteurellosis can vary greatly depending on the virulence of the pathogen, the immunological structure of the herd, housing and feeding conditions, the presence of concomitant infections and the timeliness of health measures. IN modern conditions keeping animals, pasteurellosis can occur simultaneously with other diseases: parainfluenza, infectious rhinotracheitis, adenoviral infection, salmonellosis, streptococcosis, diplococcosis; in pigs - with erysipelas, plague, salmonellosis; in chickens - with colibacillosis and staphshucoccosis. Mixed infections usually take a longer and more malignant course.

Animal pasteurellosis is observed at any time of the year, in pigs more often in March - April and September - November, in cattle in July - August and September - November.

Pathogenesis. The development and severity of the pathological process during pasteurellosis depend on the state of the animal’s body and the virulence of the pathogen. In places of penetration, pasteurella multiply, penetrate into the lymph and blood, causing septicemia and death of the animal in most cases after 12..36 hours. In development pathological processes An important role is played by the toxic products of pasteurella - endotoxins and especially aggressins, produced by the pathogen and suppressing the body's resistance. The generalization of the process is facilitated by the inhibition of phagocytosis by Pasteurella (incomplete phagocytosis) and massive damage to the capillaries. As a result, extensive swelling develops in the subcutaneous and intermuscular tissue.

Course and clinical manifestation. Depending on the virulent properties and routes of penetration of the pathogen incubation period with pasteurellosis lasts from several hours to 3 days. The disease can occur hyperacutely, acutely, subacutely and chronically.

In cattle with a hyperacute course, a sudden increase in body temperature to 41 °C, severe cardiac disorders, and sometimes bloody diarrhea are observed. The death of the animal occurs after a few hours with symptoms of rapidly increasing cardiac weakness and pulmonary edema.

Acute pasteurellosis, as a rule, occurs with primary damage to either the intestines (intestinal form), or the respiratory system (thoracic form), or with the appearance of edema in various parts of the body (edematous form). Body temperature is elevated in all forms of acute pasteurellosis.

The intestinal form most often occurs in young animals and is characterized by progressive diarrhea and weakness of animals. There are frequent cases of blood appearing in the stool. Animals experience thirst, anemic mucous membranes and increasing depression.

In the chest form, signs of acute fibrinous pleuropneumonia are noted: accelerated and labored breathing, cough, discharge from the nasal openings, first serous and then serous-purulent, pulse increased. Auscultation of the chest reveals areas of dullness, increased bronchial breathing, and sometimes friction sounds. Towards the end of the disease, diarrhea mixed with blood often develops. The illness lasts for several days. Many sick animals die, or the disease takes a subacute or chronic course.

The edematous form is characterized by the formation of rapidly spreading inflammatory edema subcutaneous tissue and intermuscular connective tissue in the area of the head, neck, dewlap, labia, and sometimes limbs. The mucous membrane of the oral cavity, the frenulum of the tongue and the tongue are swollen and bluish in color. Breathing is difficult, wheezing. Sticky saliva is released from the corner of the mouth. Animals die due to symptoms of increasing heart failure and asphyxia.

In buffaloes, pasteurellosis occurs hyperacutely or acutely with the same clinical signs as in cattle.

In sheep, acute pasteurellosis with its inherent general clinical signs of septicemia is rarely observed. Fever, severe depression general condition are accompanied by the development of edema of the subcutaneous tissue of the anterior part of the body and fibrinous pleuropneumonia. Patients die on the 2...5th day. The subacute and chronic course of the disease is characterized by symptoms of prolonged fibrinous pleuropneumonia, keratitis, mucopurulent rhinitis, arthritis and progressive exhaustion.

Sheep pasteurellosis, caused by hemolytic pasteurella, most often manifests itself as pneumonia and, less often, mastitis.

Porcine pasteurellosis most often occurs as a secondary infection, complicating plague, influenza, erysipelas and other diseases. Much less often, the disease occurs acutely, as an independent infection, characterized by the phenomena of hemorrhagic septicemia and damage to the lungs and pleura. In the case of a hyperacute course of the disease, the animal’s body temperature suddenly rises (up to 41...42 °C). Sick pigs lie down and refuse to feed. Leather ears And abdominal wall becomes bluish-purple - a sign of heart weakness. Pharyngitis often develops, and the subcutaneous tissue in the neck area swells greatly. Animals die due to asphyxia within 1...2 days. If the disease drags on, signs come to the fore fibrinous pneumonia. Appear severe cough, shortness of breath and mucopurulent rhinitis. The disease usually ends in death on the 5th...8th day. In the chronic course of pasteurellosis in sick pigs, the body temperature remains within normal limits, the cough decreases, but weakness and emaciation progress, eczema may appear, and joints may swell. Some animals survive, but most die within a few weeks.

Pasteurellosis in rabbits often manifests itself acutely; subacute and chronic courses are less common. In an acute case, the animal's body temperature suddenly rises (up to 41 "C and above) and signs of catarrh of the upper respiratory tract are noted - runny nose, sneezing. Breathing becomes difficult. The rabbit eats poorly and becomes noticeably weaker. Diarrhea appears. After 24...48 h death can occur. It is characteristic that shortly before the death of the animal, the body temperature decreases sharply. The subacute course of the disease in rabbits in most cases is the result of an exacerbation. chronic disease. In this case, clinical signs characteristic of bronchopneumonia, lobar pneumonia, and fibrinous pleurisy are observed. Diarrhea is common. Chronic manifestation pasteurellosis occurs in permanently unfavorable rabbit farms. In this case, the characteristic signs of pasteurellosis are rhinitis, conjunctivitis and keratoconjunctivitis. Breathing becomes difficult. Abscesses can be found in the subcutaneous tissue.

In birds, pasteurellosis can occur in different ways. Sometimes a completely healthy-looking bird dies. Only just before death is a depression in the general condition and a blue discoloration of the crest noted. Instant, overnight death of birds that looked completely healthy the day before, especially if waterfowl are also dying, is an important diagnostic sign of pasteurellosis. In the acute course of the disease, the bird becomes lethargic, keeps itself apart, sits in one place, and a lot of foamy mucus flows from the mouth and nasal openings. Body temperature rises to 43.5 °C, feathers are ruffled and dull. Faeces that are grey, yellow or greenish in color, sometimes mixed with blood, are passed very frequently. Cyanosis of the comb and catkins is clearly expressed. Breathing is accelerated and difficult due to the presence of thick mucus in the respiratory tract. There is no appetite, thirst increases, general weakness progresses, the bird has difficulty getting up and most often dies after 3 days.

Pathological signs. In cattle with hyperacute and acute pasteurellosis, pathological changes are characterized by multiple hemorrhages on the serous membranes, enlargement and swelling of the lymph nodes, acute gastroenteritis, often hemorrhagic in nature, but the spleen is not enlarged. Besides, typical sign is swelling in the subcutaneous tissue and intermuscular tissue in the head (pharynx and intermaxillary space), neck, dewlap, genitals and anus. Celebrate dystrophic changes in the liver, kidneys and heart.

In the chest form of the disease, especially pronounced changes are found in the lung area: lobar or necrotizing pneumonia and pleuropneumonia. The process affects individual sections of the lungs, and sometimes entire lobes. For pasteurellosis lobar pneumonia is somewhat different from the classical one - it usually spreads quickly, as a result of which marbling appears indistinctly, the exudate contains many red blood cells, necrotic foci quickly appear - dull, dirty-grayish or dark brown, the size of a pea to a fist. Regional lymph nodes are enlarged, juicy, with pinpoint hemorrhages.

When opening sheep, hemorrhages are most often found in the subcutaneous tissue, muscles, serous membranes, lymph nodes, intestines and heart. The lungs are usually enlarged, cyanotic, and foamy fluid accumulates in the trachea.

In pigs, the necropsy picture depends on the severity of the disease. If the disease is acute, then numerous hemorrhages are found on the skin, serous and mucous membranes, gelatinous-serous swelling of the subcutaneous tissue in the larynx and neck, pulmonary edema, enlargement and hyperemia of the lymph nodes.

With a prolonged course, changes in the lungs are pronounced. Pleurisy, severe compaction of lung tissue, is diagnosed. On section they have a variegated appearance due to hepatization of various stages. In addition, airless dense areas of varying sizes are found in the lungs.

In rabbits, in case of death during the acute course of the disease, numerous hemorrhages are found on the mucous membrane of the upper respiratory tract, in the lymph nodes, on the mucous and serous membranes of the intestines. Striped hemorrhages between the tracheal rings are considered especially characteristic. The lungs are hyperemic, edematous, dotted with pinpoint hemorrhages. In the subacute course of the disease, fibrinous or purulent pleurisy, lobar-hemorrhagic pneumonia are diagnosed. Chronic pasteurellosis in rabbits is characterized by changes in the mucous membrane of the upper respiratory tract and lungs, the presence of abscesses under the skin, in the lymph nodes, in the mammary gland, and in internal organs. In many cases, the mucous membrane of the stomach and intestines is inflamed. There may be small necrotic lesions in the lungs and liver.

In birds with hyperacute pasteurellosis, changes in corpses are usually absent. In some cases, exudate is noted in the cardiac sac, and pinpoint hemorrhages under the epicardium. In cases of acute disease, hemorrhages are found in the deep layers of the skin and subcutaneous tissue, almost always hemorrhages of varying sizes on the serous membranes and fat in the abdomen, sternum, and gonads (ovary). The heart sac is filled with exudate. The heart (pericardium and epicardium) is almost always covered with numerous hemorrhages and appears as if splashed with blood. Signs of enteritis are observed, with inflammation being the most pronounced duodenum. IN abdominal cavity exudate is often found. The liver is in a state of parenchymal degeneration, yellowish color, dense consistency, covered with pinpoint grayish necrotic lesions. The spleen is usually not changed.

In a disease that progresses more slowly, changes of the following nature are observed: the comb and earrings are blue, the pectoral muscles are colored dark color, hemorrhages on the epicardium, on the intestinal mucosa, the liver is enlarged, with multiple small necrotic lesions. With arthritis, a curd-like purulent exudate accumulates in swollen joints.

Diagnostics and differential diagnosis. The diagnosis of pasteurellosis is established on the basis of a complex of epizootic, clinical, pathological and laboratory studies.

Laboratory diagnosis of pasteurellosis involves: 1) microscopy of blood smears and fingerprint smears from affected organs; 2) isolation of pure culture on nutrient media with identification by biochemical properties; 3) isolation of pasteurella by infecting laboratory animals (white mice or rabbits) with a suspension from pathological material and a culture from a nutrient medium; 4) determination of the virulence of isolated cultures for white mice and rabbits. To determine the virulence of hemolytic pasteurella, 7-day chicken embryos are used; 5) determination of serovariant affiliation of Pasteurella.

As test material, blood from the superficial vessels and nasal mucus are taken from sick animals, and after death or forced slaughter - blood from the heart, lymph nodes (mesenteric, retropharyngeal, mediastinal, suprauterine, etc.), pieces of lungs, liver, spleen, heart , kidney, tubular bone. In summer, during long-term transportation, pathological material is preserved with a 30% sterile glycerin solution.

The diagnosis of pasteurellosis caused by P. multocida is considered established: 1) when virulent pasteurella are isolated from the blood or simultaneously from several parenchymal organs; 2) when isolating a culture only from the lungs of cattle or pigs; 3) in sheep, simultaneous isolation of P. haemolytica from the lungs, blood and parenchymal organs serves as the basis for the diagnosis of hemolytic pasteurellosis.

Isolation from the lungs of simultaneously weakly virulent P. multocida and P. haemolytica indicates mixed disease pasteurellosis caused by pasteurella of both species. Such pasteurellosis is diagnosed as pasteurellosis pneumonia.

When making a diagnosis, pasteurellosis must be differentiated from febrile diseases of a septic nature, which are also accompanied by the appearance of inflammatory edema under the skin: anthrax, emphysematous carbuncle and malignant edema.

Immunity and specific prevention. Animals that have recovered from pasteurellosis acquire immunity for 6...12 months. For specific prevention of the disease in Russia, more than 15 vaccines, mostly inactivated, are recommended: polyvalent emulsified against porcine pasteurellosis; lyophilized against pasteurellosis in cattle and buffaloes; sorbed against avian pasteurellosis; against salmonellosis, pasteurellosis and streptococcosis in piglets; associated against salmonellosis, pasteurellosis and enterococcal infection of piglets and live vaccine against pasteurellosis of waterfowl from strains AB and K of the Krasnodar NIVS. Vaccines are used with preventive purpose and forcedly in case of stationary troubles on farms. Intense immunity is formed on the 7...10th day after revaccination and lasts up to 6 months.

For passive immunization, hyperimmune sera are used against pasteurellosis in cattle, buffaloes, sheep and pigs.

Prevention. To prevent the disease, managers and specialists of farms and animal owners must ensure that the following measures are taken: all animals entering the farm are kept in quarantine for 30 days under veterinary control and, if indicated, vaccinated against pasteurellosis; stock herds with animals only from farms that are free from pasteurellosis; do not allow contact between farm animals and animals in personal use; have sanitary checkpoints on farms and provide service personnel with a change of clothes and shoes; protect animals from various stressful influences; in areas unfavorable for pasteurellosis, systematically vaccinate animals; farms in which pasteurellosis has been registered must be equipped with only vaccinated livestock throughout the year.

Treatment. Sick animals are injected with hyperimmune serum against pasteurellosis. therapeutic dose and one of the antibiotics (terramycin, oxytetracycline, biomycin, chlortetracycline, tetracycline, streptomycin, chloramphenicol), long-acting drugs (dibiomycin, ditetracycline, disreptomidazole, bicillin-3) or more modern drugs- enrofloxacin, etc. C therapeutic purpose pathogenetic and symptomatic agents can be used.

Control measures. When an animal disease with pasteurellosis is established, the farm (farm, brigade, department, etc.) is declared unfavorable for pasteurellosis; by decision of the territorial administration, restrictions are introduced and a plan of organizational, economic, veterinary and sanitary measures to eliminate the disease is approved.

In a farm unaffected by pasteurellosis, it is prohibited to: 1) import (export) animals outside the farm for breeding and consumer purposes, with the exception of exporting clinically healthy animals to a meat processing plant; import (export) animals susceptible to pasteurellosis; 2) regroup, mark (with violation of the integrity of the skin) animals, and also conduct surgical operations and vaccinations against other diseases; 3) graze animals from disadvantaged groups and give them water from open water bodies; 4) sell milk from animals sick or suspected of having pasteurellosis. Milk must be pasteurized for 5 minutes at 90 °C and used as animal feed. Milk from healthy cows is used without restrictions; 5) remove (remove) feed, implements, equipment and other items from the premises of dysfunctional farms; 6) transport manure and liquid fraction to the fields in an undisinfected form.

Animal slaughter products are subjected to veterinary inspection at the slaughter site. If there are degenerative or other pathological (abscesses, etc.) changes in the muscles, the carcass with internal organs is sent for disposal. In the absence pathological changes in the carcass and in the internal organs, slaughter products are sent to a meat processing plant, subject to the current veterinary and sanitary rules for the transportation of meat products.

In order to localize the epizootic focus and eliminate the disease, farm managers and veterinary specialists must ensure the following activities: 1) clinical examination and thermometry of all animals in the disadvantaged group; 2) isolation in a separate room of sick and suspected animals and assigning them special equipment and sanitary and hygienic means, as well as service personnel, including a veterinary specialist; 3) clinically healthy animals, regardless of their location, be immunized against pasteurellosis with one of the vaccines in accordance with the instructions for use.

Routine disinfection in the premises where animals are kept is carried out immediately when the first cases of disease or death appear, and then daily during the morning cleaning of premises where sick and suspected of disease animals are located. Premises, walking yards, cages (and the soil under them) where animals suspected of being infected (conditionally healthy) are kept must be disinfected after each case of isolation of a sick animal and subsequently every 10 days until restrictions are lifted, in accordance with current instructions“Carrying out veterinary disinfection of livestock facilities.”

Before the restrictions are lifted, the following measures are carried out in a troubled point: 1) repairs to the premises where sick and suspected animals were kept; 2) disinfection and cleaning of the entire farm area from manure and debris, then repeated disinfection and plowing; 3) disinsection, deratization and final disinfection of premises.

The restriction on farms (farm, team, yard) is lifted 14 days after the general vaccination of animals and the last case of recovery or death from pasteurellosis, as well as a set of organizational, economic, veterinary and sanitary measures with final disinfection.

Test questions and assignments. 1. What are the clinical and epizootological features of the manifestation of animal pasteurellosis depending on the serotype of the pathogen? 2. What factors determine the stationarity and seasonality of the disease? 3. What biomaterial should be sent to the laboratory for research and when is the final diagnosis of the disease considered established? 4. What set of measures should be carried out on a dysfunctional farm? 5. Name the means and methods of treating sick and suspected animals with pasteurellosis. 6. How to carry out specific immunoprophylaxis of pasteurellosis in animals different types?

Pasteurellosis is an infectious disease that affects the intestines, lungs and vital important systems body. Pasteurellosis affects birds, farm animals, wild herbivores, dogs and cats (they rarely get sick).

Pasteurellosis usually occurs from March to November, but can appear at any time of the year. There are three forms of pasteurellosis: cutaneous (focal infection of soft tissues), pulmonary and septic.

In all animals, pasteurellosis can occur hyperacutely, acutely, subacutely and chronically.

Pasteurellosis - dangerous disease, and can lead to serious complications. Starting treatment for the disease in the early stages can save the animal's life. If your pet lies down and does not react to the environment around it, and its body temperature is elevated, contact your veterinarian immediately. Your pet needs help.

Main signs of pasteurellosis

Symptoms of pasteurellosis depend on the degree of pathogenicity and the place where the pathogen enters the body. In the early stages, the animal lies down, does not respond to calls by name and changes around, and refuses food. In some cases, the disease begins with a rise in temperature to 41 degrees and severe diarrhea, often mixed with blood.

Breathing is heavy, with coughing and wheezing, audible at a distance from the animal. Swelling of the muscles and subcutaneous tissue often appears in the head, neck, abdomen and genital areas.

Causes and course

The disease is caused by microbes of the genus Pasteurella. The pathogen persists in water and feces for up to three weeks. In frozen products, mainly meat, they will remain more than a year. Microbes are resistant to acids and alkalis and die within a few minutes when boiled.

The pathogen spreads through the feces of sick animals and carcasses. Domestic rodents (mice, rats) do not suffer from pasteurellosis, but they transmit pathogens.

Infection occurs by drinking contaminated water or food, eating carcasses, or sniffing sick animals. The period from infection to the development of signs of the disease is called incubation. With pasteurellosis, it lasts up to three days.

Once in the body, microbes migrate into the blood and lymph. They multiply and cause sepsis. The body responds with an immediate increase in temperature. Cells are sent to the place where microbes multiply immune system, macrophages. The production of antibodies is enhanced. Some microbes die, releasing several groups of toxins. Some attract fluid and damage the membranes of surrounding cells. Swelling occurs and active enzymes enter the blood. Another group of toxins destroys the blood. In different parts of the vessels there may be red blood cells, plasma and blood clots stuck together. Oxygen delivery throughout the body deteriorates. At the same time, toxins damage blood vessels. Part: Hemorrhages occur in the internal organs, and heart failure develops.

Once the pathogen enters the lungs with air or blood, the pathogen quickly multiplies. Lung cells are damaged and pneumonia begins. Toxins produced by microbes are quickly absorbed into the blood. In the intestines, microbes multiply on the contents and damage the mucous membrane. Digestion is disrupted. The body strives to get rid of germs and speeds up bowel movements.

Within a few days, death occurs from dehydration, exhaustion and sepsis. Even with assistance, more than 50% of animals infected with pasteurellosis die.

Treatment of pasteurellosis

Treatment of pasteurellosis in domestic animals is carried out in the clinic. Manipulations are aimed at:

destruction of the pathogen;
maintaining the functioning of vital organs and systems;
reduction of action and elimination of toxins.

The destruction of the pathogen is achieved by using a special serum containing antibodies to the pathogen. Antibiotics are widely used. Tetracycline, inolir and similar drugs are used. In some cases, sulfonamide drugs are used: biseptol, metronidazole, trichopolum. Maintaining the functioning of vital organs and systems is achieved in several ways. The most important thing is to improve the delivery of oxygen throughout the body. For this purpose, blood transfusions and inhalation of mixtures containing oxygen are used. Adenosine triphosphate (ATP)-based medications may be used to improve the use of available oxygen in the body. B vitamins, cocarboxylase, and ascorbic acid are widely used.

Trimetazidine, sulfocamphocaine, mildronate, etc. can be used to maintain heart function. The choice of medication depends on the condition of the animal. Replenishment of fluid lost with diarrhea is achieved by using saline (ringer, quartasol, etc.) solutions. To maintain the vital functions of the body and extraintestinal nutrition, a 5% glucose solution, hydrolysine, lipofundin, etc. are used.

Reducing the effect and removing toxins is achieved by supporting the functioning of the liver, kidneys and the use of drugs that bind poisons. Liver function is supported by early stages enzymatic (essentiale), in later years - herbal (karsil, silybor) preparations. Canephron, lespenefril, etc. are used to maintain kidney function. Among drugs that bind poisons, glutargin, sodium thiosulfate and analogues are used.

The pathogen in an infected animal is present in feces, urine, under the claws (in cats), sputum of the nasopharynx, and is released when coughing, snorting, or with blood during bleeding.

Features of pasteurellosis

Domestic rodents (mice, rats, guinea pigs) in most cases suffer from pasteurellosis for several years without symptoms.

In birds, one form of the disease involves sudden death without signs of illness.

Dogs, cats and primates (including humans) often become infected with pasteurellosis through fights and bites, even from healthy animals. In such cases, all signs of the disease do not appear.

Due to the peculiarities of urine formation in cats, the administration of sulfonamides to them in some cases accelerates the development of urolithiasis.

Recovering from leptospirosis is accompanied in animals by the formation of non-sterile, and at the end of the period of leptospir carriage - sterile immunity of high intensity and significant duration.

For passive immunization, polyvalent serum against leptospirosis of farm and commercial animals is used. Vaccination prevents disease, abortions, eliminates reinfection of animals and the formation of an intense focus of leptospirosis. However, the vaccine, like the serum, does not free animals from leptospirosis and does not prevent abortions in infected animals.

For active immunization animals use the polyvalent VGNKI vaccine against animal leptospirosis; associated vaccine against leptospirosis and campylobacteriosis in cattle; associated vaccine against leptospirosis and porcine parvovirus infection; concentrated vaccine against animal leptospirosis; associated vaccine against emphysematous carbuncle and leptospirosis in cattle; lyophilized vaccines against animal leptospirosis; vaccine against canine leptospirosis.

Prevention And control measures. Prevention of the disease is carried out by carrying out a complex of organizational, economic, veterinary, sanitary and specific measures. This complex includes:

1) measures aimed at preventing the introduction of leptospirosis into healthy farms. All animals entering the farm are quarantined for 30 days and tested for leptospirosis. Farms are stocked only with clinically healthy animals whose serological testing has yielded negative results. To staff fattening farms, it is allowed to introduce clinically healthy animals without testing for leptospirosis, but with mandatory vaccination against leptospirosis during the quarantine period;

2) measures aimed at identifying natural foci of leptospirosis and monitoring the welfare of herds;

3) measures aimed at preventing the occurrence of leptospirosis in prosperous units of the farm located in the zone of a natural or associated with human activity (anthropourgic) focus.

If a disease occurs on the farm, restrictions are introduced. Under the terms of the restriction, it is prohibited to: export (import) animals for reproduction purposes; sell animals to the public; regroup animals without the knowledge of the veterinary specialist servicing the farm; allow animals to access water from open reservoirs and use it for watering and bathing animals; graze unvaccinated animals on pastures where animals with leptospirosis were grazed, or on the territory of a natural focus of leptospirosis; feed unvaccinated animals food containing rodents infected with Leptospira.

Sick and suspected animals are isolated and treated, the rest are vaccinated. Treated animals are vaccinated 5-7 days after recovery. Milk from sick cows is boiled and fed to livestock, and milk from clinically healthy cows is used without restrictions. Breeding stock, producers and replacement young stock, which must be preserved for reproduction, after vaccination are treated with leptospirocidal drugs and transferred to a disinfected room.

Young animals obtained after the activities are raised separately, vaccinated within the time limits specified in the instructions for the use of the vaccine against leptospirosis, and after restrictions are lifted, they are sold on a general basis.

Routine disinfection is carried out after each case of identifying a sick animal, and then every 10 days until restrictions are lifted. For disinfection, a clarified solution of calcium hypochloride containing 2% active chlorine, a 2% hot solution of sodium hydroxide, 1% iodine, etc. are used. Rodents are systematically destroyed.

Restrictions in fattening complexes and reproductive farms are lifted after the animals are handed over for slaughter, and in breeding and commercial farms - after their well-being is established by laboratory tests after 2 months, and at artificial insemination points - after 3 months after completion of the anti-voleptospirosis measures provided for by the instructions.

PASS T ERELLEZ

Pasteurellosis; hemorrhagic septicemia is a group of infectious diseases of agricultural and wild animals, as well as humans, caused by microorganisms of the genus Pasteurella.

Pasteurellosis diseases are characterized by septicemia with the development of hemorrhagic inflammation of the mucous membranes of the respiratory tract and intestines in acute cases, and in subacute and chronic cases - mainly damage to the lungs. The infectious nature of the disease was established in 1878-1887, after Bollinger (1878) described pasteurellosis in cattle, and Kitt (1885) isolated the pathogen. During these years, Pasteur conducted experiments to weaken bacterial cultures and immunized birds. In honor of his merits, the pathogen was named pasteurella, and the disease it caused was named pasteurellosis.

An analysis of the epizootic situation regarding pasteurellosis over the past 12 years shows that this disease was registered in 86 regions, territories and autonomous entities. Cattle pasteurellosis has been identified in 70 constituent entities of the Russian Federation. The disease is most widespread in the Altai Territory, the Republic of Bashkortostan, Penza, Smolensk and Ulyanovsk regions. Pasteurellosis of small cattle occurs in 15 regions of the country, of which the Krasnodar and Stavropol territories and Dagestan are the most disadvantaged. Among horses, pasteurellosis has been registered in 11 regions, territories and autonomies, especially in Bashkortostan.

In its acute form, the disease causes significant economic damage, which consists of mortality, forced slaughter, decreased animal productivity, and the costs of medical and preventive measures.

Pathogen belongs to the genus Pasteurella, family Pasteurellaceae. The genus Pasteurella includes six species: P. multocida, P. haemolytica, P. pnevmotropix, P. aerogenes, P. gallinarum and P. urea.

P. multocida includes three subspecies: P. multocida subspecies multocida, P. multocida subspecies septica and P. multocida subspecies gallicida.

According to the classification of S. Heddlieston, all pasteurella strains are divided into five serogroups according to the capsular antigen A, B, D, E, F and 16 serovars according to the somatic antigen. Hemorrhagic septicemia in farm and wild animals is caused by strains of Pasteurella serovariants B2 and B5. In the pulmonary form of the disease, to which young animals are most susceptible, they are caused by P. multocida serovariants A1, A3, A12.

The leading etiological significance in animal pathology belongs to two types of pasteurella - P. multocida, serovars A, B, D, and P. haemolitica, biotype A. P. multocida is the causative agent of hemorrhagic septicemia in animals, avian cholera, as well as pulmonary pasteurellosis, complicating respiratory infections of viral and mycoplasma etiology. P. haemolitica causes pneumonia in cattle and sheep of all ages. In addition to the listed diseases, these two types of Pasteurella can be isolated from cows and sows during abortions, from calves and lambs - during arthritis and other local pathological processes.

P. pnevmotropix is the causative agent of an enzootic disease in mice, rabbits and other laboratory animals. P. aerogenes is a permanent inhabitant of the intestinal tract of pigs. P. gallinarum is found as a commensal of the upper respiratory tract of birds, sometimes cattle. P. urea is isolated from people suffering from chronic atrophic rhinitis.

These are non-motile, gram-negative, non-spore-forming bacteria, located separately, sometimes in pairs and less often in chains. When staining smears from blood and organs, bipolarity is revealed. All Pasteurella are aerobes and facultative anaerobes. Bacteria isolated from animals of different species are similar in morphological and cultural properties, but their pathogenicity is highest for animals of the species from which they were isolated.

The resistance of the pathogen to external factors and chemicals is low. In manure, soil and rotting corpses, pasteurella remains viable for 1-3 months. When dried in the open air and the sun, they die within 48 hours, when exposed to direct sunlight - in 10 minutes. At low temperatures, pasteurellas are preserved for a long time.

In terms of resistance to chemical disinfectants, the causative agent of pasteurellosis is classified as low-resistant (first group). All disinfectants in normal concentrations have a detrimental effect on bacteria within a few minutes.

Epizootological data. Domestic and wild animals are susceptible, including birds of all types, as well as humans. Young animals are more susceptible than adults. Among laboratory animals, rabbits and white mice are easily infected.

The main source of infection is sick and recovered animals, which excrete the pathogen with mucus when coughing, with discharge from the nasal cavity, with feces and urine. From healthy microbial carrier animals, a weakly pathogenic pathogen enters the external environment. The duration of carriage ranges from several months to 1 year or more.

Infection occurs mainly through the respiratory tract (droplet infection). Nutritional contamination is often noted, especially when feeding (or drinking) skim milk obtained from the milk of sick cows, as well as through damaged mucous membranes. The spread of pasteurella by rodents and birds cannot be ruled out. Transmission factors include infected feed, water, soil, premises, care items, clothing, corpses, and slaughter products.

There are primary and secondary (secondary) pasteurellosis. The occurrence of the first is associated with the penetration of a highly virulent pathogen into the body (especially in fur-bearing animals when eating contaminated slaughterhouse waste), and the appearance of the second is due to the activation of persistent (sometimes up to a year or more) pasteurella in animals.

In temperate climate zones, pasteurellosis of farm animals occurs in spring and autumn, and of fur-bearing animals in summer. The incidence ranges from 1 to 53%, the mortality rate in acute cases can reach 70%.

According to data on the incidence of infectious diseases in pig livestock on Russian farms for 1997-2001. pasteurellosis was observed in 4% of animals, mortality was 32.7%, and the number of unfavorable points was 12.6%.

The disease can occur without the introduction of a pathogen from the outside due to a decrease in the body’s resistance and an increase in the virulence of Pasteurella found in the upper respiratory tract.

In piglets, the disease can occur as a complication after vaccination with an anti-plague virus vaccine. Stress factors include inadequate feeding (lack of vitamins, amino acids, microelements), as well as unsatisfactory living conditions (cold, rain, draft, etc.), leading to colds and damage to the respiratory tract in cold weather.

Sporadic cases are more common among cattle, sheep and pigs. In disadvantaged farms, the disease is characterized by stationarity, which can be explained by the presence of bacteria-carrying animals. When staffing farms with prefabricated livestock, the disease often occurs in the form mixed infections, since supplying farms have a different microbial landscape and immunological structure of the herd.

Pathogenesis. After the pathogen enters the body through the respiratory gastrointestinal tract, as well as through skin disorders, the pathogen multiplies, suppresses phagocytosis, and penetrates the circulatory and lymphatic systems, causing septicemia. Toxins released by the pathogen increase permeability blood vessels, which leads to swelling in the subcutaneous and intermuscular tissue, hemorrhagic diathesis.

With high resistance of the organism, as well as penetration of a weakly virulent pathogen, septicemia does not develop, and the disease proceeds subacutely or chronically. The pathogen is localized in individual bodies and tissues, causing the development of serous-catarrhal or lobar inflammation.

Clinical signs. The incubation period lasts from several hours to 2-3 days. There are hyperacute, acute, subacute and chronic courses of the disease, and according to the localization of the process and clinical manifestation - septic, thoracic, edematous and intestinal forms.

In calves the temperature rises to 40-42 "C. There is evidence that sometimes the disease can occur at normal body temperature, but with symptoms of depression. Some animals experience diarrhea, some calves die very quickly with convulsive muscle contractions and profuse salivation.

In acute cases, edematous, thoracic and intestinal forms are distinguished. With pasteurellosis in calves, the most typical symptoms are the transience of the disease and the appearance of rapidly increasing swelling in the area of the submandibular space, neck, tongue, abdomen and limbs. The swelling is hot, painful, tense, non-creating and spreading quickly. With swelling of the tongue and neck, breathing is hoarse and labored, patients have difficulty taking food, and saliva flows out of the mouth in strings. In some animals the disease is accompanied by agitation. Rapid development and increased clinical signs after 1-2 days lead animals to death.

The chest form is characterized by signs of acute fibrinous pleuropneumonia - depression, loss of appetite, difficulty breathing, dry painful cough and serous discharge from the nose. As the disease progresses, the discharge becomes serous-purulent mixed with blood, and diarrhea is observed. The animal dies within a few days, or the disease takes a chronic course, lasts for months and often ends in death.

In the intestinal form - progressive diarrhea with signs of damage to the respiratory tract. Appetite is preserved, thirst, anemia of the mucous membranes and increasing depression are observed. The disease lasts 1-2 weeks, the outcome is fatal.

In the subacute course, the disease lasts from 7 to 20 days and is characterized by symptoms of damage to the lungs and pleura, in other cases - damage to the gastrointestinal tract. Sometimes the disease becomes chronic, and animals die due to symptoms of progressive cachexia.

The chronic course is rare; it often develops from subacute. Signs of damage to the lungs and intestines are less pronounced, but the animals lose a lot of weight and their joints swell. The disease lasts a long time and often ends in death.

In the lambs the disease occurs acutely or subacutely, sometimes with lightning speed. Lambs with a lightning-fast course after the sudden onset of fever and weakness quickly die. In acute cases - fever up to 42 °C, on 2-3 days diarrhea mixed with blood and mucus develops, the mucous membranes are anemic, conjunctivitis, signs of lung damage.

In pigs the incubation period ranges from 5 to 14 days. There is pasteurellosis, which affects pigs of all age groups and only piglets. Pasteurellosis as a secondary infection is observed in other, especially viral, diseases. Pasteurellosis, which affects pigs regardless of age, is called primary; it is recorded relatively rarely. It occurs in the form of an acute septic disease or affects the lungs.

There are hyperacute, acute and chronic courses of the disease.

In hyperacute cases, the temperature suddenly rises to 41 "C, breathing is difficult, symptoms of heart failure quickly develop, redness and cyanosis of the skin appear on the lower wall of the abdomen and behind the ears. Swelling of the subcutaneous tissue often occurs, especially in the pharynx, symptoms of severe pharyngitis. Sometimes they are affected pleura and lungs. Death occurs within 24-48 hours.

The acute course (thoracic form) is manifested by a fever and fibrinous pneumonia. Shortness of breath, a strong painful dry, and later wet cough, sputum of a mucopurulent nature, sometimes containing blood, appear. As the disease progresses, breathing becomes difficult. Diarrhea often occurs, visible mucous membranes become bluish. Towards the end of the disease, due to weakening of the heart, red spots of congestive hyperemia appear on the skin. After 5-8 days, the animals die from asphyxia. Sometimes the acute course becomes chronic, which is characterized by coughing, progressive emaciation and weakness.

Pasteurellosis, which affects only piglets, proceeds as fibrinous pleuropneumonia, often with a fatal outcome. Usually the entire litter is sick. Porcine pasteurellosis most often manifests itself as a secondary infection when viral diseases, primarily for plague and influenza.

Pathological changes. With edematous form in calves extensive inflammatory swelling of the subcutaneous and intermuscular tissue is established, most often in the head and neck area, numerous hemorrhages on the serous tissues, especially the chest cavity, on the mucous membranes and in parenchymal organs; acute swelling and edema of the lymph nodes, acute catarrhal or hemorrhagic inflammation of the abomasum and small intestine, degenerative changes in the liver, kidneys and heart.

In the chest form - lobar necrotizing pneumonia and fibrinous pleurisy. The lobes of the lungs become marble-colored with numerous foci of necrosis and sequestration. In addition to defeats in chest hemorrhagic enteritis is noted.

In piglets in acute cases, an increase in the submandibular, retropharyngeal and cervical lymph nodes is detected. In the mucous and serous membranes, hemorrhages, lobar pneumonia (color Fig. 9, 10), serous-fibrinous pleurisy are detected. Bronchial lymph nodes are enlarged, juicy and reddened. The spleen is unchanged.

Diagnosis. It is placed on the basis of epizootic, clinical data, pathological changes and laboratory test results. Blood from superficial vessels and nasal mucus are sent to the laboratory from sick animals, and after the death of animals or forced slaughter - pathological material (pieces of the spleen, liver, lungs, lymph nodes, blood from the heart, tubular bone, tracheal mucus), taken no later than 3-5 hours after the death of an animal that was not treated.

Laboratory diagnosis of pasteurellosis consists of microscopy of blood smears and imprint smears from affected organs (Romanovsky-Giemsa staining with Leffler's blue is characterized by bipolarity - more intense staining of the poles of the bacterial cell. Pasteurella isolated from cattle have an elongated shape, from pigs - oval); isolating a pure culture of Pasteurella by sowing from pathological material on artificial nutrient media - meat-peptone broth and agar, broth and Hottinger's agar; identification of Pasteurella by biochemical properties; isolation of the pathogen by infecting laboratory animals with a suspension of pathological material and a culture from a nutrient medium; determination of the virulence of isolated Pasteurella cultures; determination of serovariant affiliation of isolated pasteurella.

Typing is carried out in an agglutination reaction and using a staphylococcal test (strain No. 7128) in Petri dishes with meat-peptone agar. The suitability of the opsonophagocytic reaction for intravital diagnosis of pasteurellosis has been established. The opsonophagocytic ability of the blood serum of animals sick with pasteurellosis increases already in the first hours after infection and remains at a relatively high level for several months. The same reaction can establish post-vaccination immunity.

Differential diagnosis. Pasteurellosis must be differentiated: in calves - from anthrax, piroplasmosis, emphysematous carbuncle, staphylococcal and streptococcal infections, salmonellosis, escherichiosis and respiratory viral infections; in piglets - from plague, erysipelas, hemophilus pleuropneumonia and salmonellosis; in lambs - from anthrax, piroplasmosis, clostridiosis and streptococcal infection.

Treatment. IN As a specific treatment, hyperimmune anti-pasteurella serum is used, which is administered intramuscularly or intravenously to calves, buffaloes, lambs and piglets in doses of 20-60 cm 3. If necessary, the serum is reintroduced. You can use serum from the milk of hyperimmunized cows or blood serum from producing oxen. The best effect is obtained by simultaneous use of pasteurellosis serum with antibiotics. You can administer penicillin and streptomycin at a dose of 4000-6000 units, as well as biomycin at a dose of 10,000-20,000 units/kg 1-2 times a day for 3-4 days, oxytetracycline (terramycin) at a dose of 4000 units/kg. They are administered intramuscularly once a day for 3 days. Erythromycin is effective. It is injected into sick 3-4 month old piglets at a dose of 5000 IU/kg intramuscularly 2 times a day for 2 days. Before administration, the drug is dissolved in 2-3 cm 3 of ethyl alcohol and an equal volume of distilled water is added to it.

Good results are achieved by using the antibiotics dibiomycin and ditetracycline at a dose of 30,000-70,000 units/kg or mycerin - 15,000-20,000 units/kg for 3-4 days, as well as orimicin, which is administered intramuscularly, intravenously (slowly) or subcutaneously at the rate of 4-10 mg/kg 2 times a day for 5-7 days. It is advisable to give calves and lambs orally in a group method with food or individually 3 times a day ampicillin in single doses at the rate of 20 mg/kg of animal weight, for Species B with food 2 times a day for 3 days in a row (mg/kg of animal weight): for calves - 40-60 and piglets - 50.

In the absence of specific serum, only antibiotics can be used for treatment. Good results are obtained from the use of terramycin (oxytetracycline), biomycin (chlortetracycline), tetracycline, streptomycin, levomycetin. Terramycin is administered intramuscularly at a dose of 10,000 units/kg 1-2 times a day for 3-5 days, streptomycin is administered intramuscularly at a dose of 15,000 units/kg 1-2 times a day for 3-5 days, chloramphenicol orally at a dose 15-20 mg/kg of animal weight 2-3 times a day for 3-5 days. For pasteurellosis in piglets with lung damage, good results were obtained from aqueous and oily solutions of penicillin, dihydrostreptomycin, and an alcohol solution of erythromycin. Effectively intramuscular injection Biomycin in the form of 1% once a day for 3 days aqueous solution at a dose of 0.5 cm 3 /kg, as well as neomycin, gentamicin, chlor-nitromycin and carbenicillin.

At the same time, sulfonamide drugs are used (norsulfazole, sulfazine, etazol, sulfantrol, phthalazole, sulfadimezin). They are given along with food 2-3 times a day for 3-4 days in doses of 0.02-0.05 g/kg of animal weight. Intramuscular administration of bicillin-5 at a dose of 10,000-20,000 units/kg once is effective.

Ampicillin is used with food 3 times a day at a rate of 30 mg/kg of animal weight, ecmonovocillin is administered intramuscularly at a dose of 5000-10,000 units/kg once a day for 5-7 days. Chloramphenicol is used - 30-40 mg/kg of animal weight. Vitatetrin is administered orally at the rate (mg/kg animal weight): calves - 40, piglets - 60 2 times a day for 5-7 days. Calves, lambs, kids are injected intramuscularly with monomycin at a dose of 5-10 mg/kg 2 times a day for 5-7 days; solvovetin at a dose of 0.1-0.2 mg/kg with an interval of 12 hours for 5-7 days; streptosulmicin sulfate (mg/kg): calves - 5, piglets - 20 every 12 hours for 5-7 days. Lomaden is used as an aerosol in a 0.5% concentration at a rate of 5-7 cm 3 /m 3. Orally - baytril (enrofloxacin) at a dose of 2.5 mg/kg of animal weight per day for 3-5 days. Effective are ribamidil, which is given orally to calves at a dose of 0.05 g/kg animal weight 4 times a day for 5 days, rovatisine - to piglets with food once a day at a dose of 0.1 g/kg animal weight for 10 days. days.

For preventive purposes, lambs and calves are given Biovit-40, 80, 120, respectively, in doses (mg/kg animal weight) of 300-500, 150-200 and 80-100.

According to V. Z. Geletyuk, the combined use of antibiotics and sulfonamides provides a 100% therapeutic effect, and the use of neomycin and sulfonamides makes it possible to prevent the emergence of drug-resistant pathogens.

If diarrhea occurs, in addition to sulfonamides, piglets are also given oral astringents: thealbin or tannin in a dose of 2-3 g per head, potassium permanganate with drinking water diluted 1:10,000 in a dose of 0.5-1l. When cardiac activity weakens, a 20% solution of caffeine salts is injected subcutaneously at a dose of 0.5-2 cm 3.

Immunity. Animals that have recovered from the disease acquire immunity for 6-12 months.

The bioindustry of our country produces 15 vaccines against pasteurellosis: 6 emulsified (one each for ruminants and pigs in mono- and polyvalent versions, polyvalent for pigs, monovalent for cattle, buffaloes and sheep), 7 aluminum hydroxide (semi-liquid for large cattle and buffaloes, precipitated for sheep and pigs, associated against salmonellosis, pasteurellosis and streptococcosis of piglets, associated against salmonellosis and pasteurellosis of pigs, mono- and polyvalent for the pasteurellosis component), as well as for birds, minks and nutria, associated with pas- sterellosis-bordellosis vaccines “Dessau” (Germany), “Solco-rinitella” (Switzerland).

In addition to vaccines, 3 anti-pasteurella serums are produced: for cattle, buffaloes, sheep and pigs (monovalent VGNKI), for pigs, rabbits and fur-bearing animals (polyvalent) and polyvalent against pasteurellosis, salmonellosis, parainfluenza-3 and infectious bovine rhinotracheitis (VIEV , VGNKI, VNIITiBP).

Prevention and control measures. All animals entering the farm must be kept in quarantine for 30 days under veterinary control and, if indicated, vaccinated against pasteurellosis. During the year, farms where pasteurellosis has been registered must be equipped with livestock vaccinated against this disease at the supplying farm or during the period of preventive quarantine. The introduction of unvaccinated animals into the herd within a year after its recovery is prohibited.

On farms, it is necessary to carefully carry out veterinary and sanitary measures and observe zoohygienic conditions for keeping and feeding animals in order to prevent the introduction of infection from the outside and a decrease in the body’s resistance. Fattening farms in areas unaffected by pasteurellosis should be completed only after immunization of animals imported from different areas.

Since pasteurellosis is a respiratory infection, and the pasteurellas themselves are ubiquitous with a wide range of pasteurellosis, it is necessary to protect animals from general and local hypothermia, to prevent production stress, especially in groups of post-preventive young cattle and growing piglets.

If a disease occurs on the farm, restrictions are introduced and a clinical examination of the entire population of the affected herd is carried out. Sick and suspected cases are isolated and treated. All patients and animals in contact with them are administered hyperimmune serum against pasteurellosis in a therapeutic dose and one of the antibiotics (terramycin, oxytetracycline, biomycin, chlortetracycline, streptomycin, as well as long-acting drugs: dibiomycin, ditetracycline, bicillin-3). The remaining animals of the farm, regardless of their location, are immunized with one of the vaccines against pasteurellosis in accordance with the instructions for use; Before vaccination, a thorough clinical examination and thermometry are performed.