鳥類における実験的真菌症

第1編・Mucoraceaeに属する3種の真菌による鳩の経気道感染実験

抄録

By 3 days-long inhalation of the air containing the spores of Absidia ramosa, Rhizopus oryzae or Mucor pusillus respectively in high concentration, ten pigeons were subjected to experimental mucormycosis. All pigeons showed neither remarkable weight-loss, nor clinical symptoms or signs including anorrhexia and diarrhea in 5 or 12 days clinical observation after inoculation.
All pigeons were sacrified at 5 or 12 days after inoculation and subjected to autopsy. A marked bleeding was observed in gross examination on the surface of lungs, while no remarkable gross findings in heart, liver, spleen, kidneys and G. I. -tracts in all cases inoculated with 3 strains respectively.
Histological examination revealed a moderate or marked bleeding in bronchus, bronchioles and also pulmonary parenchyma with a few hyphal elements. As to the intensity of bleeding, the Absidia ramosa inoculated group showed much marked bleeding than the groups inoculated with Rhizopus oryzae or Mucor pusillus. Generally speaking, inflammatory responses such as edema or cellular infiltration were less predominant in all groups. The giant cell response around the hyphal elements was observed in only one pigeon inoculated with Absidia ramosa at 12 days after inoculation. The other organs were not remarkable on microscopic study. Namely, it seemed that the pigeons transtracheally inoculated with spores of 3 genera of Mucoraceae respectively failed to develop systemic mucormycosis by the method used in this experiment. Positive cultures of respective strain were obtained from the lungs, but not from the other organs in all pigeons.