Current treatment methods and preventive countermeasures of porcine hyperpyrexia syndrome

In recent years, high fever in pigs has persisted, that is, the so-called "high fever syndrome" in pigs has occurred more frequently, which has brought serious losses to the pig industry, so that many pig farms have closed down and many farmers are afraid to raise pigs. Porcine high fever syndrome (HPS) is a compound infectious disease characterized by persistent high temperature, loss of appetite and redness of skin in sick pigs. It is mainly caused by Eperythrozoon suis, porcine pseudorabies, atypical swine fever, blue ear disease, circovirus disease and infectious pleuropneumonia, and most of them are mixed infection or secondary infection. Since the onset in June last year, the incidence and etiology are different from those in previous years, and some new features have emerged. Therefore, we summed up some feasible treatment methods and preventive countermeasures in the diagnosis and treatment research. The following is for peer reference:

Main clinical symptoms of 1

The sick pig's body temperature rises by 40OC-42OC, loss of appetite or abandonment, mental depression, tears in eyes, inability to lie flat, dyskinesia, shortness of breath, runny nose, dry and hard feces, yellow urine, red skin all over the body, or cyanosis in abdomen and ear tips; Or purple blood spots appear at the root of the ear, abdomen, inner limbs, etc. Or blue eyes, blue around the anus. A few days after the onset, some pigs have yellow or pale skin, and a few pigs have needle-like bleeding in their pores. Some pigs have diarrhea, trembling and emaciation. Edema around limbs and eyelids, swollen lymph nodes on the body surface. Boars are infertile, sows are not easy to conceive, and pregnant pigs are prone to premature birth, stillbirth and mummification.

2 autopsy changes

From the autopsy of sick pigs, the pathological changes of sick pigs are mainly lung changes, some lungs are pale, some have bleeding spots and bleeding spots; Some pulmonary edema, mottled to brown marble-like lesions, and some substantial degeneration, such as sponginess, can float in water; Some are like boiled water; There are also many diseased pigs with meat quality changes in many parts of their lungs, especially in the leading edge of pointed leaves, heart leaves and diaphragm leaves, and some diseased bronchi are full of purulent secretions; There are many bubbles in the trachea, and some tracheal ring mucosa is congested. Myocardial hemorrhage, pericardial effusion, pale yellow liquid. The liver is grayish white; Some have necrotic foci; Some have bleeding spots, some are swollen and yellowish brown, and there are yellow stripes or gray-white necrotic foci on the surface. The kidney is swollen, brown or khaki, fragile and congested; Some have a large number of needle-like bleeding spots; Some show typical marble patterns; Some have necrotic spots and spots. The spleen is enlarged, and there are many infarcts at the edge. Gastric congestion and bleeding; Some pigs have gastric mucosal bleeding, necrosis and ulcer, and there are a large number of ulcer foci in ileocecum. Intestinal bleeding is serious, especially in the small intestine and colon. Lymph nodes are widely enlarged, especially inguinal lymph nodes and hilar lymph nodes. Some sick pigs have laryngeal mucosal edema and bleeding, and pig bladder mucosal bleeding. Individual pigs showed multiple serous cellulose pleurisy and peritonitis.

3 Laboratory inspection situation

Enzyme-linked immunosorbent assay (ELISA) was used to detect mycotoxins in swine fever, swine flu and feed, and RT-PCR was used to detect porcine reproductive and respiratory syndrome virus (PRRSV), pseudorabies virus (PRV) and porcine circovirus (PCV-II). The isolated bacteria were identified by biochemical test, and Toxoplasma gondii and Eperythrozoon were detected by spleen contact method and blood smear method respectively. According to laboratory examination, it was found that the incidence of swine high fever syndrome this year was different from previous years (200 1 -2005). Before 2005, Eperythrozoon infection was the main infection in clinic, and mixed infection of Eperythrozoon with blue ear disease, pseudorabies and streptococcus was rare. After June this year, the incidence of blue ear disease, pseudorabies and circovirus was significantly higher than last year. Viruses are mainly porcine reproductive and respiratory syndrome virus (PRRSV), porcine circovirus (PCV-II), swine influenza virus (SIV), pseudorabies virus (PRV) and classical swine fever virus (HC), and bacteria are mainly Actinobacillus pleuropneumoniae (APP), Haemophilus parasuis (HP), Streptococcus suis type 2 (SS-II) and Streptococcus suis.