Pig neck red, swollen and gasping to death? It is very simple to make good vaccine prevention (1)

Pathogen and Epidemiology

Pig lung disease, many farmers also call it "lock throat wind", it is caused by Pasteurella multocida infection in pigs, all stages of pigs are susceptible to infection, especially fattening pigs. This kind of bacteria can infect many kinds of animals, including humans, pigs are called porcine lung disease, cattle are called cattle failure (hemorrhagic septicemia), rabbits, chickens, ducks and sheep are also easily infected. Infected livestock and poultry are the main sources of infection, and feces, secretions and contaminated feed, drinking water and utensils are all ways of transmission. Pathogens brought by coughing and sneezing are most likely to infect other animals and can be transmitted through skin wounds and blood-sucking insects. Therefore, there are two main reasons for the high incidence of the disease in summer, one is the stress of hot and humid environment, and the other is the infection caused by flies and mosquitoes. In addition, some adverse factors such as long-term malnutrition, long-distance transportation, parasites and poor sanitary conditions will promote the occurrence of the disease.

Clinical and autopsy symptoms

According to the symptoms, porcine lung disease can be divided into three types: the most acute septicemia, acute type and chronic type.

The most acute septic type: there are symptoms of septicemia, often sudden onset, quick death. After some pigs were infected, they ate well on the first night and showed no symptoms, but they were found dead in the pigsty the next morning. The main symptoms are redness, swelling and fever in the throat under the neck, hard to touch with hands, and severe swelling extending to the base of the ear and chest. Slightly chronic, there will be a high fever of 41 ℃-42 ℃, waste food, lying on the floor can not afford, or sitting in the dog posture, neck stretched out to breathe, white foam in the mouth and nose. A slightly slower death rate of 1-2 days, with a mortality rate close to 100%. After autopsy, it was found that there was acute hemorrhagic edema in the throat and a lot of translucent yellowish fluid.

Acute type: chronic infection of porcine lung disease, not treated in time to die in about 4-6 days. This is a more common type of porcine lung disease. The body temperature is generally between 40 ℃ and 41 ℃. It begins with a dry cough and later becomes a wet cough, dyspnea, elimination of sticky nose, and sometimes with bloodshot. Although there is no obvious redness and swelling in the appearance of the neck and chest, the pig will show pain when touching, with purple spots or small bleeding spots on the skin. Finally emaciated and powerless, unable to afford undercover, suffocated and died. Autopsy revealed one or both sides of fibrinous pneumonia, the lung lesions were partially enlarged, solid, dark red or grayish red, which was significantly different from the normal pink.

Chronic type: chronic porcine lung disease mostly shows the symptoms of chronic pneumonia, poor spirit, poor appetite, persistent cough, wheezing, a small amount of thick secretions in the nasal cavity, and gradually lose weight. If not treated in time, he will die of exhaustion in about two weeks, with a mortality rate of about 65%.