Isolation and pathogenicity of mycoplasmas from geese

Several mycoplasma isolation trials were performed on infertile goose eggs and goose embryos which died during incubation, as well as on geese of different ages. A total of 43 out of 110 goose eggs proved to be contaminated by mycoplasmas. Upon autopsy of birds which laid positive eggs, lesions were observed in the airsacs. Mycoplasmas could be isolated from their air sacs and oviduct. Four out of 15 strains examined biochemically and serologically with antisera prepared against all known avian mycoplasma species were identified as Acholeplasma laidlawii and A. axanthum, respectively. Two strains proved to be glucose-positive and arginine-negative and 9 were glucose-negative but arginine-positive. Some strains caused 50-80% mortality among embryos inoculated intra-yolk-sac at 12 days. In goslings inoculated at the age of 3 days with these strains, we observed fibrinous airsacculitis and peritonitis. By inoculating laying geese with one of the strains, we demonstrated decreasing egg production, increasing early-embryo mortality and egg transmission of mycoplasmas.