Syngamus trachea causes the condition of ‘gapes’ in birds particularly in chicken, turkeys, geese and quail. Available literature did not reveal any record of Syngamus trachea in ducks. The present study describes a case of Syngamus trachea in a duck.

A total of 10 dead and sick ducks brought to the Deptt. of Pathology were necropsied. Diagnosis was given on the basis of clinical, gross and microscopic examinations. For clinical examination, blood, undigested material from intestine, caeca, rectum and also the faeces were collected from the ducks. For gross and microscopic examinations, trachea, lungs, liver and intestines were collected in 10% formalin for histopathology.

As per owner's statement, sick ducks showed signs of weakness, closed eyes, movement of head forward and upwards, open beak during respiration, shaking of the head and very little feed intake.

Feacal samples from sick ducks and undigested food material were examined by sugar floatation and direct smear method. Eggs of Syngamus trachea were observed. Haematological parameters showed anaemia, heterophilia, monocytosis, oesinophilia and lymphocytopaenia.

Necropsy examination revelaed congested lungs and pneumonia. Trachea showed oval shaped nodule at the posterior end, which was cartilaginous in nature and contained (Syngamus trachea) worms (Fig.). Calnek et al.¹,² reported that these nodules were produced as a result of an inflammatory reaction at the site of attachment of the male worm in chickens, pheasants and turkeys. Tracheal mucosa revealed blood tinged exudates and worms. Livers were congested and enlarged. Duodenum showed pin point hemorrhages.

Histopathologically, trachea revealed desquamation of columnar epithelium, haemorrhages, congestion and catarrhal tracheitis. Eosinophils and heterophils were observed in submucosa. Lungs showed bronchopneumonia. Alveoli and bronchioles were filled with serous exudate besides infiltration of eosinophils and erythrocytes. Liver revealed hepatitis and infiltration of eosinophils, heterophils and monocytes. Duodenum showed haemorrhages.

The clinical, gross and microscopic features were in corroboration with findings of previous workers ¹,²,³ in chickens, geese, pheasants, turkeys and quail.

Fig.:Cartilaginous nodular growth at the end of trachea.

Syngamus trachea infection in a duck