A virus in chronic respiratory disease of turkeys.

Abstract

IN the chronic respiratory disease syndrome of chickens and ducks, both a virus and pleuropneumonia-like organisms have been etiologically implicated1. Serological studies on infectious sinusitis of turkeys, utilizing a haemagglutination-inhibition test, indicated that there is a relationship between presence of antibodies against the pleuropneumonia-like organisms and a clinical sinusitis2. However, in some birds, infection with the pleuropneumonia-like organisms did not result in development of a sinusitis. Observations on field-outbreaks of chronic respiratory disease and their relation to the onset and severity of sinusitis in turkey flocks seemed to indicate that the pleuropneumonia-like organisms did not serve to define the etiology of these syndromes. This became apparent in two outbreaks when it was demonstrated that a large percentage of the birds were serologically positive to the pleuropneumonia-like organisms prior to the onset of respiratory symptoms, and furthermore that sinusitis was observed in only 2–5 per cent of the birds. Within two weeks after the onset of the respiratory symptoms, 40 per cent of the birds in one flock and 60 per cent of the birds in the other flock developed sinusitis.