Date of this Version
The direct life cycle of Capillaria columbae (Rud.) was confirmed. Complete embryonation of the ova takes place in shallow layers of distilled water at 30 C. within 6 to 7 days. Twenty-four hours after the ingestion of the ova by chickens, the larvae can be found penetrating the intestinal mucosa. The worms mature in 21 days at which time fertile non-embryonated ova are found in the feces of the parasitized birds. A severe infection with C. columbae was experimentally produced in chickens. The clinical symptoms and weight records of the parasitized birds showed that this parasite was pathogenic for fowls and heavy infections caused loss of weight, emaciation, and death. The lesions consisted of a catarrhal enteritis with desquamation of the intestinal epithelium. The comparative ease with which parasitized pigeons may transmit C. columbae to chickens suggests the necessity for the elimination of pigeons in any control program. The attempt to prevent infection by feeding mash, in which was mixed 2% tobacco dust by weight, was unsuccessful. Individual treatment of birds with single doses of carbon-tetrachloride and tetrachlorethylene likewise was not successful.