"Swine fever unknown" swine high fever syndrome, is a high incidence and mortality of the disease occurs mainly in the incubation period of pig and pig disease part of sows, the main clinical manifestations were fever, depression, loss of appetite or waste away, difficulty breathing, breathing, accompanied by redness of the skin purple pig etc. the symptoms, a few pores are bleeding.
Pig high fever syndrome. The main pathogens for various viruses and bacteria, parasites mixed infection and secondary infection, including swine fever virus (HCV), porcine reproductive and respiratory syndrome virus (PRRSV), swine influenza virus (SIV), pseudorabies virus (ADV), porcine circovirus type 2 (PCV-II) and pig Actinobacillus pleuropneumoniae (APP), type 2 (SS-II) of Streptococcus suis and Haemophilus parasuis disease (HP), Pasteurella multocida (PM), mycoplasma pneumonia (MH), Toxoplasma, Eperythrozoon, Salmonella choleraesuis (SC) mixed infection of bacteria.
From the beginning of the end of May 2006, many farms in some areas, growing finishing pigs and sows, piglets outbreaks of unknown swine fever, most swine have swine incidence in more than 50%, the mortality rate as high as 50 to 90%, causing serious economic losses to the pig farms and pig farmers, some farms because of it bankruptcy.
Due to the complex etiology, is generally a multi pathogen mixed infection, clinical is difficult to control, the treatment effect is not ideal, resulting in slow growth or stagnation, sick pigs and pig dead pigs increased, feed efficiency, growth rate and the whole herd uniformityreducing, treatment costs increase, the pig production suffered severe loss.
Disease characteristics
1. occurred in the high temperature season, the disease process is long, generally in about 5~20 days, high mortality.
2. pig farms do not pay attention to the epidemic prevention work, and the technical staff have poor health care concept. There is no strict closed pig farm, and the pig farm with systematic health care is not serious.
3., the incidence of pig weight generally in 20 ~ 80kg, the highest incidence, but also after weaning piglets.
4., the effect of drug treatment is not ideal, and the mortality rate of the pig farm with indiscriminate use of drugs is higher.
Clinical symptom
The onset of the pig body temperature increased to 40 ~ 42.5 DEG C, depression, decreased feed intake or appetite waste away, suffering from pig skin redness, ear ear edge cyanosis, abdomen and legs endings multiple skin patches, with purple red; dyspnea, like recumbent pigs, part of abdominal breathing, severe the shortness of breath or asthma, some showed irregular breathing; some have swine runny nose, sneezing, coughing, eye secretions, most pigs have tear stains, causing conjunctivitis symptoms; some swine feces constipation, constipation, spherical, yellow urine, and less turbid, color. Slightly longer course of disease, pigs pale, anemia, hair rough disorder, part of the disease, the hind legs of the pig weakness, the individual diseases of the pig can not stand before dying, and finally died of convulsions. The mortality rate of pigs is high, and some pigs even reach 50 ~ 90%. Some sows have miscarriages in the late pregnancy (100~110 days), stillbirths, mummies, and mummies.
Necropsy change
All the dead pigs showed pneumonia at different degrees. The following symptoms were found in the necropsy:
1. swelling of the lungs and harden; a rubber cannot shrink like pulmonary interstitial pneumonia, pulmonary symptoms, showing the mottled brown lesions (marble) to; most are mixed infection with pneumonia, suppurative foci, partial lung hemorrhage, hemorrhagic pneumonia, interstitial widened significantly.
2. lymph nodes are enlarged widely, especially in the inguinal lymph nodes and hilar lymph nodes.
Some 3. pigs died of liver swelling, the color fades, some liver is loess color, crisp, individual pig, bladder, throat, heart fat and coronary sulcus bleeding heart inside and outside the film; some of dead pig kidney enlargement, dark brown or yellowish brown, crisp texture, with blood stasis phenomenon. Some cases of pig spleen swelling, crisp.
4. multiple serous fibrinous pleurisy and peritonitis with fibrin exudation in the pleural cavity and abdominal cavity. Individual lung and pleural or pericardial serous fibrinous adhesions.
Control measures
The cause of this disease is complex, disease of pigs poor healing, prevention should adhere to the prevention, through strengthening feeding management, improve sunstroke prevention and health care, in advance, strengthen disinfection work, symptomatic treatment and other measures to reduce its incidence and mortality.
1., adhere to the principle of self support to prevent the purchase of recessive infection of pigs.
2., pay attention to the pig breeding management, try to reduce all kinds of stress factors:
The summer should Fangshujiangwen, increase the amount of ventilation and cooling measures piggery with cold water spray, evaporation and convection through promoting heat dissipation; piggery doors and windows should be fully open, let the air convection. When the temperature is high, rinse the pig body with cold water or spray it. Spray it 4~6 times a day;
The summer should reduce the breeding density, the growth of pigs should have living space of 0.8 square meters, the best finisher is 1.2 square meters per head, number of pigs per pen is best in 10 to around 12, to maintain a reasonable feeding density and cooling can effectively control the unknown swine high fever and respiratory disease.
From the birth, conservation, breeding to strictly by feeding all in all out, to avoid too large difference of day old pigs mixed group feeding, reduce the pigs fence and mixed group number, so the same barns and pigs all turn out, in each batch of pig slaughter pigs after she must be washed and sterilized strictly, vacant after a few days and then transferred to the new herd.
3. pig house and environment should be disinfected regularly to reduce pathogens