Complete Guide to Porcine Circovirus Prevention and Treatment, a Must-Read for Pig Farmers
Porcine circovirus infection is an immunosuppressive infectious disease caused by PCV-II, characterized by post-weaning multisystemic wasting syndrome and dermatitis and nephropathy syndrome. Its main manifestations include physical decline, emaciation, pallor, diarrhea, and the formation of red-purple spots on the skin.
The disease was first reported by Canadian scholars in 1991, and in recent years it has occurred in many countries and regions around the world. In China, the disease was first reported in 2000, and at present, in areas of China with @#@227@#@ high pig-raising density and on farms with poorer feeding management, the occurrence of this disease is becoming increasingly widespread, and the harm to the pig industry is becoming increasingly serious.
I. Pathogen
Porcine circovirus type II (PCV-II) belongs to the family Circoviridae, genus Circovirus, and is a single-stranded DNA virus without an envelope. It is one of the smallest members among animal viruses. PCV-II has a certain resistance to acid, chloroform, and high temperature. This virus is synergistic with PRRSV.
II. Epidemiology
Sick pigs and virus-carrying pigs are the main sources of infection. The virus is shed from the body through feces and nasal secretions. Piglets are mostly infected at 4-5 weeks of age and 11-13 weeks of age, mainly through the digestive tract. Morbidity and mortality rates vary among different farms, and various stress factors can aggravate the occurrence of this disease.
III. Clinical Symptoms
PCV-II causes progressive functional failure of multiple systems. The main symptoms are lethargy, reduced appetite, poor growth and development, progressive emaciation, pale and anemic skin, and dry skin lacking luster. Some sick pigs develop jaundice, and growing pigs pass yellow loose feces, often in mixed infection with PRRS. The carcass is emaciated, pale, and anemic. Growing pigs often develop dermatitis, with red papules forming on the skin.
IV. Pathological Changes
The main lesions are enlargement of systemic lymph nodes by 4-5 times, earth-yellow in color, with a homogeneous cut surface. The lungs are reduced in volume, with scattered raised rubbery hard nodules on the surface, congestion, hemorrhage, and widened interstitium. The spleen is enlarged and blackened, especially with very obvious enlargement of the splenic head. The liver is stained yellow, and the kidneys are enlarged, pale, with white necrotic foci, and edema of the tissue around the renal medulla. The stomach has large areas of ulceration or hemorrhage near the esophageal region, and severe cases can cause gastric mucosal hemorrhage and ulceration.
V. Comprehensive Prevention and Treatment
(I) Drugs: Flubikang 20 grams (or amoxicillin 20 grams) + Keduxian 400 grams + compound vitamin B 50 grams + glucose 500 grams per 100 jin of feed or water, continuously fed for 7-10 days.
(II) There is still no reliable vaccine available for clinical use, so drug prevention and health care work should be done well. Add the Chinese herbal compound preparation Keduxian at 2000-3000 ppm to the feed, and carry out preventive health care for sows before and after farrowing; provide health care for piglets before and after weaning, and at the same time do a good job in preventing PRRS, which can achieve effective prevention and treatment results.
(III) Strengthen feeding management, implement all-in-all-out, early isolation weaning, and feeding by parity; reduce stocking density, pay attention to ventilation and air exchange, strengthen warmth preservation work, and reduce stress; strengthen hygiene and disinfection work.
(IV) Strengthen nutrition, select highly nutritious and easily digestible creep feed and nursery feed, and improve the nutritional level of the pig body.