Prevention and control of porcine circovirus

Porcine circovirus infection (Porcinecircovirwsinfection) is an immunosuppressive infectious disease characterized by postweaning multiple system failure and dermatitis nephropathy caused by PCV- Ⅱ, which is characterized by physical decline, weight loss, pallor, diarrhea and reddish-purple spots on the skin.

The disease was first reported by Canadian scholars in 1991 and has occurred in many countries and regions in the world in recent years. The disease was first reported in China in 2000. at present, in the areas with high density and poor pig farms, the occurrence of the disease is more and more widespread, and the harm to the pig industry is more and more serious.

I. pathogen

Porcine circovirus type Ⅱ (PCV- Ⅱ) belongs to the single-stranded DNA of circoviridae, without envelope, and is one of the smallest members of animal viruses. PCV- Ⅱ has a certain resistance to acid, chloroform and high temperature. This virus cooperates with PRRSV.

II. Epidemiology

Diseased pigs and infected pigs are the main sources of infection. the virus is excreted through feces and nasal secretions. Piglets are mostly infected at the age of 4-5 weeks and 11-13 weeks, mainly through the digestive tract. The morbidity and mortality are different in different fields, and various stress factors can aggravate the occurrence of the disease.

III. Clinical symptoms

PCV- Ⅱ causes multiple systemic sexual failure. The main symptoms are loss of spirit, loss of appetite, growth retardation, progressive weight loss, pale and anemic skin, dry and lack of luster. Some of the diseased pigs have jaundice, growing pigs pull yellow thin feces, often mixed with PRRS infection. The body was emaciated, pale and anemic. Growing pigs often form dermatitis and red papules on the skin.

IV. Pathological changes

The main lesions were enlarged lymph nodes of the whole body 4-5 times, yellowish, and the section was homogeneous. The volume of the lungs shrinks, with rubber lumps scattered on the surface, congestion, bleeding, and broadening of the stroma. The spleen is enlarged and blackened, especially the enlargement of the spleen head is very obvious. Yellow staining of the liver, enlargement of the kidney, pallor, white necrotic focus, edema of the tissue around the renal medulla. The stomach has a large area of ulcer or bleeding near the esophagus, and serious cases can cause gastric mucosal bleeding and ulcers.

V. Comprehensive prevention and control

(1) 20 grams of flurbikang (or 20 grams of amoxicillin) + 400 grams of Keduxian + 50 grams of compound vitamin B + 500 grams of glucose / 100 jin of feed or water for 7-10 days.

(2) there is no reliable vaccine for clinical use, so it is necessary to do a good job of drug prevention and health care, adding traditional Chinese medicine compound preparation Keduxian 2000-3000ppm to feed for prevention and health care of sows before and after weaning, health care of piglets before and after weaning and prevention of PRRS can play an effective prevention and treatment effect.

(3) strengthen feeding management, carry out full-entry and full-exit, early isolation of weaning, feeding according to fetal times, reduce feeding density, pay attention to ventilation, strengthen heat preservation, reduce stress, and strengthen sanitary disinfection.

(4) strengthen nutrition and select teaching materials and nursery materials with good nutrition and easy digestion to improve the nutritional level of pigs.