[ Riemerella infection (Infectious Serositis) [

 

Riemerella anatipestifer Infection

Riemerella anatipestfer (RA) infection, duck septicaemia, new duck disease or anatipestifer syndrome. It is a worldwide septicaemic disease of ducks, turkeys and other birds, caused by Riemerella anatipestfer, characterized by serositis, salpingitis, meningitis, and locomotor disturbances and reduced body weight.

 

Economic importance

Etiology

Cellular morphology

Culture media

Colonial morphology

Biochemical features

Natural hosts

Experimental hosts

It can be reproduced by intravenous, subcutaneous, intramuscular, and intraocular routes in ducks, and chickens.

 

Mode of transmission

Clinical disease

Post mortem lesions

Diagnosis

Plate agglutination test (PAT).

Tube agglutination test.

Gel diffusion precipitin test (GDPT).

Fluorescent-antibody technique (FA).

* Using agglutination test, 19 serotypes have been reported, while only 7 serotypes were reported by GDPT.

* The FA technique may be used to detect and identify RA cells directly in tissues or exudates from infected birds.

• Serologic detection in the host (Indirect serologic test):

The serologic response of ducks to RA antigens appears to be poor, because of the development of low agglutination titers, 10-14 days after infection. ELISA, using cell lysate as an antigen, is more sensitive than PAT and GDPT and can be used for early detection of infection.

 

Differential diagnosis

Treatment

Prevention: through good management and sanitary measures.

 

Immunity to infection

Immunization

 

(A) Inactivated bacterin

Prepared from predominant and locally isolated serotypes. Used at second and third week of age, producing immunity till marketing age. Disadvantage in producing local reaction at immunization sites.

 

(B) Living vaccine

It is non-virulent. It is used at 1-day-old of age by aerosol in drinking water. A single vaccination provides protection for at least 42 days through local mucosal and hurnoral immunity.

b. Biochemical characters and growth on MacConkey agar.

c. DNA restriction endonuclease analysis (REA) and PCR.

d. Serological identification by microtitre agglutination test (MAT) and ELISA using antigen derived from whole cells.

 

Differential diagnosis

It should be differentiated from I. sinusitis, anatipestifer infection, I. coryza, Fowl cholera, SHS.

 

Control and prevention

Treatment

it is best as aerosol or parenteral application.

Spectinomycin (20 mg/kg/b.w.).

Oxytetracycllin (OTC).

Penicillin-G sodium

• Management and care

 of other bacterial pathogens is best line of Prevention.

• Vaccination

It is not applied in Egypt but available commercially as:

(a). Living temperature sensitive mutant (TS). as aerosol.

(b). Whole cell bacterin as I/M application.