Evaluation of a Mycoplasma gallisepticum strain exhibiting reduced virulence for prevention and control of poultry mycoplasmosis.

Two experiments were conducted to evaluate the virulence and vaccination efficacy of a Mycoplasma gallisepticum (MG) isolate designated MG Intervet 6/85. Virulence of the strain was determined by evaluation of airsacculitis scores following aerosol exposure to the isolate before and after 10 sequential passes in either commercial broiler chickens or commercial turkeys. Two-week-old specific-pathogen-free chickens were vaccinated by aerosol exposure. The birds were challenged with the R' strain of MG at either 4 or 8 weeks post-vaccination. Efficacy was evaluated by airsacculitis scores determined 21 days after challenge. Ten repetitive back-passes of the isolate in chickens and turkeys did not substantially increase the virulence. Virulence for both chickens and turkeys was minimal, while protection elicited by aerosol vaccination in young chickens against virulent R' strain was significant (P less than or equal to 0.05) compared with unvaccinated controls.

[1]  K. Whithear,et al.  Immunogenicity of a temperature sensitive mutant Mycoplasma gallisepticum vaccine. , 1990, Australian veterinary journal.

[2]  K. Whithear,et al.  Safety of temperature sensitive mutant Mycoplasma gallisepticum vaccine. , 1990, Australian veterinary journal.

[3]  E. Barbour,et al.  Comparison of Mycoplasma gallisepticum subunit and whole organism vaccines containing different adjuvants by western immunoblotting. , 1989, Veterinary immunology and immunopathology.

[4]  K. Karaca,et al.  Response of chickens to inoculation with a temperature-sensitive mutant of Mycoplasma gallisepticum. , 1986, Avian diseases.

[5]  H. Yoder,et al.  Efficacy of experimental inactivated mycoplasma gallisepticum oil-emulsion bacterin in egg-layer chickens. , 1985, Avian diseases.

[6]  M. Lin,et al.  Bacterins and vaccines for the control of Mycoplasma gallisepticum. , 1984, Israel journal of medical sciences.

[7]  M. Lin,et al.  Evaluation of attenuated strains of Mycoplasma gallisepticum as vaccines in young chickens. , 1984, Avian diseases.

[8]  K. Sh,et al.  A classification of laboratory strains of avian mycoplasma serotypes by direct immunofluorescence. , 1983 .

[9]  L. Grumbles,et al.  Immunogenic potency of oil-emulsified Mycoplasma gallisepticum bacterins. , 1981, Avian diseases.

[10]  T. Carpenter,et al.  Control of Mycoplasma gallisepticum in commercial laying chickens using artificial exposure to Connecticut F strain Mycoplasma gallisepticum. , 1979, Proceedings, annual meeting of the United States Animal Health Association.

[11]  R. K. Page,et al.  Infectious coryza: preventing complicated coryza with Haemophilus gallinarum and Mycoplasma gallisepticum bacterins. , 1978, Avian diseases.

[12]  H. Adler,et al.  Immunization against Mycoplasma infections of poultry. , 1960, American journal of veterinary research.

[13]  H. Adler,et al.  Studies on chronic coryza (Nelson) in the domestic fowl. , 1956, The Cornell veterinarian.

[14]  H. Adler,et al.  Preparation of a new pleuropneumonia-like organism antigen for the diagnosis of chronic respiratory disease by the agglutination test. , 1956, American journal of veterinary research.

[15]  J. Prier,et al.  Immunological and serological studies on infectious sinusitis of turkeys. , 1951, The Cornell veterinarian.