Prevention and treatment of diseases in pigs in winter and spring

The disease is an infectious disease of piglets caused by Salmonella. The morbidity and mortality of piglets aged from 1 to 4 months were high. The disease is endemic or sporadic and often occurs in cold, changeable climate and overcast and rainy seasons. poor environmental hygiene and decreased resistance of piglets can induce the disease.

Symptoms and pathological changes in the early stage of acute onset, similar to classical swine fever, need to be combined with other examinations, the typical symptoms are persistent dysentery, chronic process, some piglets also have pneumonia symptoms. Lesions: acute cases often died of shock, extremities congestion was purple, the whole body showed septicemia changes-serous mucosal hemorrhage. In chronic cases, there are typical necrosis and ulcer of colorectal mucosa, or diffuse necrosis of mucous membrane; thickening of intestinal wall and loss of elasticity; small spot necrosis of the liver.

The diagnosis, prevention and treatment of acute cases can be confirmed by isolating pathogens from parenchyma organs, and chronic cases should be diagnosed by laboratory diagnosis. Prevention is the main cause of the disease, and attention should be paid to improving feeding management and sanitary conditions. Suckling piglets and weaned piglets aged over 1 month in frequent occurrence area were immunized with attenuated vaccine and vaccinated according to the instructions. After the onset of the disease, dysentery and sulfonamide can be used twice a day for 3-5 days. And thoroughly clean and disinfect the enclosure.

Porcine asthma disease

The disease is a chronic respiratory disease of pigs caused by Mycoplasma hyopneumoniae. Pigs of different breeds, ages and genders can be infected, and southern pigs and imported pigs are very susceptible to disease in the north. The occurrence of cold, humidity and climate change is higher, and the feeding management and sanitary conditions have a great influence on the disease. The disease is mainly caused by respiratory tract infection. The mortality rate of pregnant sows in newly infected pigs is higher than that of piglets in old disease groups, and the mortality is higher in cases of secondary infection and mixed infection. The disease can slow down the growth of diseased pigs by about 12% and reduce feed utilization by 20%.

The newly diseased pigs with symptoms and lesions showed dyspnea, abdominal breathing, inactivity, high mortality, and no fever in sick pigs; acute type was more common in new-onset pigs, showing lethargy, reduced food intake, and breathing times up to 120 times per minute. Open mouth, mouth, nose foam, sitting dog posture, can be asphyxiated to death, tolerant pigs turn to chronic type. Chronic pigs show emaciation, burnt hair, stop growth and development; dry cough on the back of the bow, neck stretching, and head drooping until secretions in the respiratory tract are coughed up and swallowed; during feeding and driving exercise in the early morning, there is a continuous spastic cough, sometimes 10 or 20 times in a row, standing still when coughing; in the later stage, dyspnea, increased frequency, asthma, emaciation and weakness of sick pigs occur. The characteristic lesion is the apical source of the lungs on both sides. Blister skin and blister fluid are the most contagious, and the recovered pigs can carry the virus for more than 150 days.

3. Both direct and indirect contact can spread, and the disease can be caused by infection in the digestive tract, respiratory tract and uninjured mucous membrane and skin. Air is also an important transmission vector. The virus can spread with the wind at a distance of 50 to 100 kilometers, showing a long-distance and leaping outbreak.

Symptoms and pathological changes of pigs are lethargic, with a rise in body temperature of more than 41 ℃, loss of appetite or loss of appetite, showing that the crown, forks and toes of the hoof are swollen and pale at first, and then form blisters, which are transparent or turbid yellowish liquid in the blisters, leaving a red festering face after rupture, and blisters and festering often occur on lips, tongues, gums, upper jaw, nose and nipples, and salivate a lot. Sick pigs limp, some hoof shells are deformed or fall off, and it is difficult to stand on the ground. Postmortem examination of the piglets showed that the yellowish markings on the surface of the myocardium alternated with the red color of the myocardium, with endocardial and epicardial bleeding. The fatality rate of foot-and-mouth disease to adult pigs is generally no more than 3%, and miscarriage may occur in pregnant sows. The symptoms of blisters in piglets, especially in lactating piglets, are not obvious, but they can die quickly in a short period of time due to myocarditis and gastroenteritis.

The clinical characteristics of diagnosis and treatment of pig foot-and-mouth disease are very similar to swine blister disease, swine vesicular stomatitis and swine vesicular rash. The disease materials should be sent to the laboratory for diagnosis. It is easy to diagnose according to symptoms and lesions (neutralization test and cross immune test or complement fixation test can be done if possible).

The principle of prevention is "early, fast, strict and small". "early" is early education, early census, early detection: "quick" is quick action, quick culling, quick disinfection, fast immunization: "strict" is strict implementation of epidemic prevention measures: "small" is the smallest epidemic spot, and the loss is the least. In peacetime, we should strengthen feeding management and strictly implement veterinary health and epidemic prevention measures. Immediately report the disease, determine the diagnosis, delineate the epidemic areas and spots, carry out strict blockade and disinfection, and do harmless treatment to sick and dead pigs. Vaccinate the susceptible animals in and around the epidemic area immediately. Can be used 2% or 4% caustic soda water, 10% lime water, or 100 poison, sodium hypochlorite strict, thorough and complete disinfection. When the epidemic situation is extinguished, livestock in the epidemic area and surrounding areas should be vaccinated for 2 or 3 years.

The vaccine and immunity are immunized with a porcine foot-and-mouth disease vaccine with the same serotype. The immunization time of sows was one and a half months before delivery (mainly to protect newborn piglets), boars in September and December every year, 30-40 days after birth, and fattening pigs were strengthened again at the age of 100 days.