Pasteurellosis in pigs is one of the most dangerous diseases found in these domestic animals. With this disease, the blood becomes infected with pathogenic microorganisms that cause hemorrhagic inflammation of the intestines and upper respiratory tract. Pasteurellosis is rapidly spreading among the stock.
General characteristics of the disease
Pasteurellosis is an infectious disease caused by the motionless bacterium Pasteurella, which grows quickly on ordinary nutrient media. The infectious origin of this disease was proven in the second half of the 19th century.
The causative agent is active in water for 3 weeks, in the body of a dead animal - up to 4 months, in frozen meat - up to 12 months.
Pasteurella is not resistant to disinfectant solutions: it dies one minute after treatment with phenol (5%) and creolin (5%). The bacterium is also sensitive to high temperatures: indicators within 70-90 degrees contribute to the inactivation of the pathogen within 5-10 minutes.
Pasteurella dies when treated with a solution of copper sulfate (1%) and milk of lime (5%). This pathogen is also adversely affected by ultraviolet rays.
Penetrating into the body of a pig, the bacterium penetrates the lymph and begins the process of reproduction. As a result of the vital activity of pathogens, toxic substances are produced that increase the permeability of blood vessels. The bacterium is localized in the alveoli of the lungs, in which there is a lot of oxygen.
As a result of the activity of pasteurella, edema is formed, increased bleeding develops.
The animal’s immune system produces a large number of antibodies that die along with pathogens. Because of this, mucous masses are formed, which clog the passages of the respiratory tract, and also provoke sneezing reflexes, which cause the further spread of bacteria.
Pig pasteurellosis is common throughout the world. In Russia, cases of this disease are most often recorded in the Central European part. The peak incidence occurs in the period of early spring and autumn.
Causes of the disease and transmission
The development of pasteurellosis is due to such provoking factors as:
- non-observance of sanitary and hygienic standards in the premises in which the livestock is kept;
- malnutrition of animals, lack of vitamins in it;
- too many individuals in the room;
- high level of humidity in the room;
- hypothermia;
- weakened immunity;
- non-compliance with the vaccination schedule.
- sick pigs and animals that have suffered this disease;
- healthy animals that have been in contact with infected individuals;
- blood-sucking insects;
- rodents;
- wild birds;
- kitchen and slaughter waste that has not undergone heat treatment and is used as feed additives;
- a person who is a carrier of this bacterium;
- contaminated soil;
- contaminated water;
- milk from an infected sow feeding piglets;
- waste of sick pigs;
- low-quality, virus-infected feed.
Pigs become infected with pasteurellosis by fecal-oral and airborne droplets. Pathogenic microorganisms enter the body through damaged skin, mucous membranes, and respiratory tract.
Symptoms of pasteurellosis are often observed in pigs that have recently suffered other diseases.
Symptoms of the disease depending on the form
The incubation period of pasteurellosis lasts from several days to 14-16 days. The term depends on the resistance of the animal to this disease. Symptoms of the pathological process depend on the form in which the disease occurs.
The following basic forms of pasteurellosis are known:
- Super sharp. In this case, infected individuals die quickly - in a day or two after the first symptoms of the pathology appear. The manifestations of pasteurellosis in a super-acute form include an increase in body temperature up to 42 degrees, shortness of breath. Sick pigs lose their appetite. They quickly get tired, there is a pronounced weakness, apathy. For this form of the disease, a disturbance in the activity of the heart muscle, the appearance of bluish spots on the surface of the legs, ears, and thighs are also characteristic. There is inflammation of the mucous membranes of the respiratory tract.
- Sharp. With this form of the disease, animals rarely survive, death occurs 3-8 days after the onset of the pathological process. Acute pasteurellosis is characterized by a sharp rise in temperature to 41 degrees, loss of appetite, shortness of breath, cough. Discharge from the nasal passages may occur, in which traces of blood may be present. Cyanotic spots form on the lower part of the abdomen, patch and ears. If the disease proceeds for a long time, a strong cough occurs, limbs swell.
- Subacute. This form of pasteurellosis leads to the death of pigs on 5-8 days after the onset of the pathological process. This type of pasteurellosis is characterized by fever, chills, cough, shallow breathing. While exhaling, sick individuals make moans. Cyanotic spots form on different parts of the body, stool disorders occur.
- Chronic This form of pasteurellosis is quite rare. The death of an infected individual occurs in 1-2 months. Symptoms of this type of disease are persistent cough, swollen joints, rapid weight loss. Also, in sick individuals, eczema patches appear on the skin. All these symptoms are observed against a background of normal body temperature.
Pathological changes depend on the duration of the disease and the severity of the pathological process. They are expressed in the following:
- hemorrhages in the larynx, lungs, myocardial membrane;
- serous edema in the sternum and neck;
- swelling of the mucous membrane of the larynx;
- digestive tract inflammation;
- changes in the structure of vascular walls.
It is possible to determine the form of the disease only with the help of diagnostic studies.
Diagnostic Methods
If dangerous symptoms appear that make it possible to suspect pasteurellosis in pigs, you must immediately contact the veterinary service.
To make an accurate diagnosis, differential diagnosis is mandatory. Pasteurellosis is distinguished from plague, erysipelas, pneumonia of viral origin, salmonellosis. To do this, use a mixture of antibiotics with serum against pasteurellosis.
Also, a biosample and culture are required to make a diagnosis.
Pig pasteurellosis treatment
Infected animals with confirmed pasteurellosis are placed in a warm and dry, well-ventilated area. An obligatory component of treatment is a full-fledged high-quality diet.
Infected animals must be given serum against pasteurellosis.
Individuals who suffer from this disease are given systemic antibiotics throughout the entire therapeutic course. The causative agent of this disease is adversely affected by the following drugs:
- Cephalexin;
- Tetracycline;
- Chloramphenicol;
- Enrofloxacin;
- Streptomycin.
Isotonic chloride or glucose is administered intravenously.
Sick animals are prescribed symptomatic preparations to maintain the activity of the heart muscle - Mildronate, Trimetazidine.
The course of treatment necessarily includes ascorbic acid, glucose, and B vitamins.
In severe cases, blood transfusion is indicated, as well as inhalation with oxygen-containing mixtures.
With pasteurellosis, the following recommendations must be observed:
- isolate sick pigs in spacious rooms;
- regularly provide animals with high-calorie feed and clean water;
- Ventilate the premises containing infected pigs daily.
The temperature in the rooms in which sick animals are kept should be within + 10-15 degrees.
Buildings are sanitized daily. A suspension of freshly slaked lime (10-20%) or a solution of bleach (2% active chlorine) is suitable for processing.
Pigs that have died from pasteurellosis are burned or disinfected in deep holes. Their waste products are also disinfected and disposed of.
If pasteurellosis is detected in the livestock complex, a quarantine regime is introduced. The list of mandatory events for this period includes:
- restriction of import and export of animals;
- a ban on walking and watering contact animals;
- the appointment and conduct of a treatment course for infected individuals;
- administration of antibiotics and serum to piglets and contact animals;
- a ban on the export of non-disinfected animal waste products, litter, slurry;
- burning carcasses of dead animals in compliance with all sanitary and veterinary standards;
- daily disinfection of the quarantine room.
All quarantine restrictions are removed 14 days after mass vaccination and the cessation of the pathological process.
Prevention
In order to prevent pasteurellosis among pigs, it is necessary:
- to withstand newly arrived animals in quarantine for a month;
- to provide workers of the economy with special clothing and equipment, as well as to require complete sanitary control;
- refuse to purchase animals on farms that are considered unfavorable in terms of sanitary and veterinary standards;
- limit contact of adults and piglets with animals from other households;
- to carry out routine vaccination activities for pigs.
To stop the development of the infectious process in the area where an outbreak of this disease is observed, it is necessary:
- limit the export of animals outside the enterprise;
- destroy the corpses of pigs killed by pasteurellosis at special stations;
- disinfect skins;
- administer serum and antibiotics to all animals that have been in contact with infected individuals;
- kill rodents in the premises where pigs are kept, as they are potential carriers of infections;
- regularly sanitize pig walking areas;
- do not take out feed and equipment from a dysfunctional pasturellosis economy;
- Do not export manure from sick animals to the fields;
- to disinfect the waste products of sick individuals.
Restrictions of a preventive nature are removed 2 weeks after fixing the last case of the disease.
Vaccination
In order to stop the development of the disease among pigs, it is necessary to carry out routine vaccination. Today it is the most reliable way to prevent the infection process among livestock.
A special vaccine against pasteurellosis consists of cattle blood.
In modern veterinary medicine, the following drugs are used:
- inactivated PPD vaccine;
- vaccine against salmonellosis, streptococcus and pasteurellosis of piglets;
- SPS-2 vaccine.
Piglets born from unvaccinated sows are vaccinated on days 12-15. If the females were vaccinated, then piglets are vaccinated against them on the 30th day of life. Re-enter the serum after 35-40 days.
Immunity after vaccination lasts for 6 months. After the specified period ends, it is necessary to repeat the introduction of the vaccine.
The introduction of a vaccine does not necessarily guarantee the protection of a pig, because its immunity can be undermined by poor nutrition and insufficiently comfortable living conditions. That is why it is important to take care of creating full conditions for the existence of animals.
Pasteurellosis is a dangerous infectious disease that affects pigs. The causative agent of the disease causes changes in the structure of internal organs and most often leads to the death of a sick individual. The most effective way of prevention is regular vaccination of pigs.