Hatcher and Intraflock Transmission of Mycoplasma meleagridis

Abstract

Mycoplasma meleagridis is widespread in turkey flocks throughout the United States and Canada (1-3,7,15). The prevalence of the organism and of airsacculitis in day-old poults from many flocks (2,7,15) and in cull poults in successive hatches (4) indicates that the organism is egg-borne. One site of infection in the adult female is the oviduct; from there the organism has access to the developing egg (9,13). In the male, the organism, which may be present in the phallus, gains access to the semen during ejaculation (9). Thus, the organism may be disseminated rapidly throughout the laying flock during artificial insemination (9,13). Airsacculitis, the primary lesion produced by M. meleagridis, present in affected poults at hatching, is reported to regress in approximately 16 to 30 weeks (1,3). The organism has been recovered from the sinus of turkeys with sinusitis; in such instances the morbidity is extremely low, and M. gallisepticum, an agent frequently associated with sinusitis, is not implicated. However, sinusitis as part of the usual clinical picture has been questioned since this manifestation could not be reproduced experimentally (5,7,10). Although overt respiratory signs are seldom associated with M. meleagridis infection, isolation of the organism from the sinus and trachea of turkeys having no apparent lesions (14) may indicate that the organism does spread by contact. Transmission by contact during hatching also has been suggested (11). This study was made to determine whether hatcher and intraflock transmission might play a role in dissemination and perpetuation of this organism.