A Detailed Guide to the Diagnosis and Treatment of Duck Infectious Serositis

Duck infectious serositis is a contagious, acute or chronic infectious disease caused by Riemerella anatipestifer, mainly affecting ducklings 1-8 weeks of age. This disease is characterized by fibrinous pericarditis and fibrinous airsacculitis, and is an infectious disease that severely harms ducklings.

1 Clinical symptoms

The most acute cases die suddenly without visible symptoms. The main clinical manifestations of acute cases are: depression, reduced food intake, refusal to eat, lying prone in a corner, weak legs, unwillingness to walk, ataxia, and when lying prone on the ground, the head tilts upward and backward with spasmodic nodding movements; some lean forward and fall backward, some cry out, and after falling over they lie on their backs and are not easy to turn over; some have the head and neck bent at about 90° and spin in circles. The course of the disease is generally 1-2 days.

2 Pathological necropsy

The pathological changes in the affected ducks of these 2 cases were basically the same, and the main lesions are:

(1) Heart lesions: in acute cases the pericardial fluid increases, and the surface of the epicardium is covered with pale yellow fibrinous exudate; in cases with a slower course, the heart is wrapped by pale yellow fibrous material.

(2) Liver lesions: the liver is clay-yellow or brownish red, enlarged and friable, and the gallbladder is enlarged.

(3) Air sac lesions: in some cases the air sacs are covered with a fibrinous membrane.

(4) Gizzard lesions: the cut surface of the parenchyma of the gizzard shows hemorrhage, and in some the koilin layer is easily peeled off.

3 Diagnosis

Based on the clinical symptoms and characteristic pathological necropsy changes of the affected ducks, a preliminary diagnosis of duck infectious serositis was made.

4 Treatment

(1) For affected ducks, human-use gentamicin was administered at 0.5 ml per duck by pectoral muscle injection, twice a day for 2 consecutive days.

(2) For healthy ducks, human-use gentamicin was uniformly given to each duck by preventive intramuscular injection, twice a day for 2 consecutive days.

(3) Through timely medication and improvement of rearing conditions, along with disinfection of the contaminated site. The condition was brought under control on the first day, no cases occurred by the third day, and by the seventh day follow-up visits showed no affected ducks.