Paratyphoid Infection in Poultry

Paratyphoid Infection

g   Causative agent – Salmonella typhimurium

Transmission

g   Humans, rhodents, wild birds, insects, pigeons, water and feed are the sources of infection.

Signs

g   Affected birds are depressed, reluctant to move, have ruffled feathers and drooped wings.

g   Diarrhoea with pasting of vent.

chickens are drowsy, with eyes closed, ruffled feathers and grouped near the sources of heat.

Gross Lesions

g   Visible lesions  are not a must but one can see septicemic carcass with swollen liver, spleen, lungs and kidneys.

In the liver, hyperaemia, subcapsular haemorrhages and dystrophy

 

g   Inflamed unabsorbed yolk sac is a common feature. 

g   The most characteristic feature is typhilltis.

g   Caeca distended with hard white necrotic cores.

caeca are filled with gelatinous, fibrinous, cheese-like exudate. This is a finding, characteristic for salmonellosis,

 

g   Septicaemia, pericarditis and perihepatitis.

Histopathology

g  Congestion, haemorrhages, infiltration of mononuclear cells with degenerative changes and focal areas of necrosis in liver. 

g   Catarrhal enteritts with inflammatory cells and necrosis. 

g   Degenerative changes and focal areas of necrosis with hyperemia and presence of a few inflammatory cells in heart. 

Diagnosis

g   Confirmation by isolation and identification of causative agent

g   Liver, gall bladder, yolksac, intestines, caecal contents are the best sites for isolation of the organism.