Prevention and treatment of Infectious serositis in Duck

Duck infectious serositis, also known as Pasteurella anatipestifer, is a chronic or acute septic infectious disease that infects ducklings (goslings). It is characterized by fibrinous pericarditis, pericarditis, pneumocystitis and arthritis. With the rapid development of duck industry and the expansion of poultry trade, the incidence of duck infectious serositis is increasing year by year, and it is easy to occur and difficult to treat, which has become one of the important diseases restricting the rapid development of duck industry. Controlling and eliminating the disease is of great significance to promote the rapid development of duck industry. Combined with the reality of my work, I talk about my experience in the prevention and treatment of the disease.

Pathogen: the pathogen of the disease is Pasteurella anatipestifer, Gram staining negative, bacteria are small bacilli, some oval, capsular, Wright staining showed a few bacteria at both ends of the thick staining. The colony was inhemolytic and showed a small dew bead on the chocolate Agar plate. It could not grow on ordinary Agar and McConkey medium. Most of Pasteurella anatipestifer survived no more than 3-4 days on solid medium at 37 ℃ or room temperature, and broth culture could be preserved for 2-3 weeks under 4 ℃. The activity was lost after incubation at 55 ℃ for 12-16 hours. It can survive in water and cushion for 13 days and 27 days, respectively.

Epidemiology: the disease often occurs at the turn of autumn and winter and the turn of spring and summer. In general, it mainly occurs in ducklings and goslings at the age of 1-8 weeks. In particular, ducklings aged 2-3 weeks are the most susceptible, and ducks over 8 weeks old rarely get sick. Adult ducks have a rare disease, but they can carry bacteria and become a source of infection. The disease is mainly infected through respiratory tract or skin wound, and can also be transmitted vertically by planting eggs. Contaminated feed, drinking water and air are all important ways of transmission. Excessive density of nursery, poor ventilation, moisture and malnutrition are all causes of the disease.

Symptoms: the incubation period of the disease is generally 1-3 days, sometimes as long as 7 days, the disease of young ducks is more urgent, often under stress conditions, sudden onset, and no obvious symptoms and die quickly. The diseased ducks with a longer course of disease include lethargy, depression, solitude, loss of appetite or abandonment, shaking head and neck, elevated body temperature, shortness of breath, discharge of secretions from eyes and nose, eye contamination, weakness of legs, movement disorders, and some neurological symptoms. paroxysmal spasm, discharge of yellow-green, stench and thin feces. A few diseased ducks showed arthritis symptoms such as lameness and inability to afford to lie on the ground. The ducklings at the age of 1-2 months showed subacute or chronic process, constantly chirping, ataxia, sometimes turning in circles, sometimes falling back, dysplasia, gradual weight loss, exhaustion and death. Due to different feeding and management conditions, the mortality rate varies greatly, generally 10%, 30%, and as high as more than 50%.

Pathological changes: the pathological changes of acute cases were systemic dehydration, hepatosplenomegaly. The course of the disease is a little longer, and there is cellulosic inflammatory exudation on the serous surface. The main manifestations are pericarditis, pericardial effusion, fibrous exudate in pericardium, hepatomegaly larger than normal, showing khaki or grayish brown, brittle texture, covering a layer of gray-white or grayish-yellow cellulose membrane, easy to peel off, fibrinous perihepattis, fibrinous balloon inflammation, yellow-white caseous exudate at the back of abdominal balloon, and some salpingitis and arthritis.

Diagnosis: in veterinary clinic, a preliminary diagnosis can be made by comprehensive analysis of epidemiology, clinical symptoms and pathological changes. If we want to make a diagnosis, we can take laboratory methods such as microscopic examination and bacterial culture. when bacteria are isolated and cultured, they can be cultured in blood medium and then inoculated on the identification medium for identification.

Prevention and treatment: the incidence of the disease is high and widespread, so comprehensive prevention and control measures must be taken.

Strengthen feeding and management. Supply ducks with high-quality, comprehensive and adequate feed, maintain reasonable ambient temperature, air humidity and feeding density, strengthen the exercise of ducks, change bedding materials in time, do a good job of ventilation and ventilation, and improve the physique of ducks.

Rational use of medicine. Sulfonamides, streptomycin, gentamicin, erythromycin, chloramphenicol and tetracycline are all effective against Pasteurella anatipestifer, but due to the abuse of antibiotics in recent years, the drug resistance of bacteria is increasing day by day, therefore, it is best to do drug sensitivity test first, targeted use of drugs, and timely change of drugs to improve the curative effect. In the prevention and control, sulfamethazine is usually added to the feed and fed continuously for 3 days. Do a good job of disinfection and vaccination. In order to prevent the emergence and spread of the disease, duck houses, feeding troughs, water tanks and places where ducks are often active should be disinfected regularly, and the inactivated vaccine of Pasteurella anatipestifer should be vaccinated. Strict quarantine. Strengthen the supervision and management of goose and duck farms and incubators and purchase necessary epidemic prevention equipment. We should strictly check the vaccination and disinfection and the supply of vaccines, and do a good job in transport quarantine and market quarantine to prevent the emergence and spread of the epidemic.