Pathogenicity to Chicks of Mycoplasma Associated with Turkey Airsacculitis

An airsacculitis not caused by Mycoplasma gallisepticum has been known in turkey poults for some years (3,6,7,12,117). Such airsacculitis may increase general morbidity and mortality. With the intensive program currently being conducted to eliminate M. gallisepticum from turkeys used for breeding purposes, the finding of airsacculitis in turkey poul~ts free of M. gallisepticum is a cause of indecision and consternation for the flock owner and for the diagnostician. Occasionally, sinusitis without airsacculitis has also been observed in semimature turkeys free of M. gallisepticum. Thus, delineation of the cause of such airsacculitis and sinusitis is of importance. Mycoplasma sp. other than M. gallisepticum have been recovered frequently from air-sac lesions in turkeys free of M. gallisepticum, and occasionally from sinus exudates of turkeys and Japanese quails. Although the pathogenicity of M. gallisepticum for chickens and turkeys has been well established, the role of these other Mycoplasma sp. needs clarification (12,17). Day-old chickens were used in this research since they have proved to be an excellent tool in the study of pathogenicity of avian Mycoplasma (15). In addition, it is difficult to obtain turkey poults from flocks free of Mycoplasma (3,6,7,12,17). Reported here are pathogenicity studies in day-old chicks of Mycoplasma spp. other than M. gallisepticum.