What if there is eperythrozoonosis in pigs?

Porcine eperythrozoonosis (eperythrozoonosis for short) is not a new disease. it was reported in India as early as 1932, but it has not been noticed. Only in the past two years, the disease suddenly increased, occurred and prevalent in many parts of the country and pig farms, and attracted people's attention. The disease is characterized by anemia, jaundice and fever. Its harmfulness lies in the economic loss caused by the decline of pig production performance, including the increase of intestinal and respiratory system infection, the decline of sow fecundity, the delay of fattening pig market and so on.

The main results are as follows: 1. Pathogenic eperythrozoon was previously considered to be a kind of protozoa, and the disease caused was called "borderline disease". According to the biological characteristics, it is considered to be a kind of rickettsitic body. Fuhong corpuscles are sensitive to dryness and chemicals. General disinfectants can kill them in a few minutes, but they have strong resistance to low temperature.

2. Epidemic characteristics: pigs of all ages and breeds are susceptible, but foreign breeds are more susceptible, sows, weaned piglets and well-growing shelf pigs are more common, and the symptoms are more serious. The disease is transmitted in at least four ways: blood-borne, contact, vertical and vector insects, while mosquitoes, stinging flies, lice and midges in blood-sucking insects are the main vectors.

Epidemiological investigation shows that the occurrence of the disease is consistent with the occurrence of mosquitoes, and the same cases can be replicated by natural inoculation with mosquitoes. The occurrence of the disease is affected by many factors, such as delivery, long-distance transportation, poor feeding management, cohort, feed changes, etc., all contribute to the occurrence of the disease. In particular, adverse factors such as high temperature and dampness in summer and autumn, breeding and biting of blood-sucking insects, large-scale and intensive feeding, as well as contaminated injection needles, surgical instruments, tail-cutting, broken teeth and ear numbers of piglets may promote the incidence of pig infection.

3. The incubation period of clinical symptoms is about 6-10 days, and the course of disease varies from a few days to several years. Most of them showed recessive infection or chronic wasting process, and the clinical symptoms were not obvious. Acute infected pigs first appeared pneumonia, showing high fever, pale skin and mucous membrane, emaciation, slow growth, cyanosis and necrosis of limbs, especially at the edge of the auricle, sometimes jaundice and diarrhea; daily weight gain of fattening pigs decreased, prone to acute hemolytic anemia. In the later stage, enteritis is often secondary to diarrhea. Pigs with chronic diseases show anemia, emaciation, and often become stiff pigs. Porcine eperythrozoon can exist in pigs for a long time, and cured pigs can carry bacteria all their lives.

Sows show acute infection, loss of appetite, persistent high fever (40-42 ℃), anemia, shortness of breath, pale skin, less milk or no milk, mostly postpartum; chronic infection sows emaciation, weakness, anemia, jaundice, tissue bleeding, but also reproductive disorders, such as reduced pregnancy rate, delayed estrus, abortion, stillbirth and so on.

4. The diagnosis of porcine eperythrozoon is mainly through direct microscopic examination, including blood pressure smear and smear staining. Can take ear vein blood 1 drop and 1 drop of normal saline mixed, evenly coated, and then covered with glass slides, with high-power mirror to good visual field, with oil mirror examination. There are many methods of serological examination, such as complement fixation reaction, indirect hemagglutination, fluorescent antibody, ELISA and so on. PCR method is also used for diagnosis abroad.

5. In principle of prevention and treatment, drugs should be used early. The commonly used drugs are Xuechongjing, yellow pigment, arsanilic acid, tetracycline, oxytetracycline, kanamycin, gentamicin and so on. At the same time, auxiliary symptomatic treatment and disinfection should be carried out. If you can use sterilized injection water or normal saline or 5% glucose injection to mix the blood worm into a concentration of 3% murine 5%, intramuscular injection according to 4 mg / kg body weight, arsanilic acid according to 300 mg / kg feed, mix and take for a week, 90 mg / kg feed for prevention, and mix for 1 month.