Anærobic infection in animals : discussion on Professor Gaiger's paper Mr. Dalling's views.

  • Dalling, Thomas.
Date:
[1924?]
Catalogue details

Licence: In copyright

Credit: Anærobic infection in animals : discussion on Professor Gaiger's paper Mr. Dalling's views. Source: Wellcome Collection.

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    It may be of interest here to state briefly otir procedure in the identifying of anserobic cultures. When a culture is received or isolated, it is examined microscopically for evidence of obvious contamination. If the organism be a sporing one, sporulation is encouraged by growth on meat containing media, and capillary tubes filled with the sporulating medium are heated at 80CC. for twenty minutes in an endeavour to kill off all vegetative forms, leaving the spores viable for further work. Cultures made from the heated material are used for colony production work, both on the surface and in the depth of solid media. Personally, I greatly prefer the surface colony method, using blood agar as a medium and a direct stream of hydrogen as a means to create efficient anserobiosis. Individual colonies are picked off and cultures from them are subjected to further plating after growth in different media, e.g., milk, alkaline, egg, etc. This plating is continued till we are reasonably sure that a pure culture is present. Sugar fermentation tests are now carried out and noted. Guinea-pigs are inoculated intramuscularly with the now so-called t£ pure ” culture and the post-mortem effects studied. Cultures are filtered and the toxicity in guinea-pigs and mice observed. Lastly, guinea-pigs are protected with the various anserobe anti-sera, and several M.L.D.’s. of the culture are inoculated. By such means one is fairly safe in concluding which anserobe one is dealing with and whether one or more types are present. Mr. Gaiger has pointed out that the lesions pro¬ duced in sheep by artificial inoculation with cultures of B. chauvoei and Vibrion septique are identical. I agree with this, and it would not be unreasonable to expect to find Vibrion septique as a cause of Black- quarter in cattle and sheep in this country. We have received samples of muscle taken from cattle dead of Blackquarter from eight different districts in Britain and have been able in each case to isolate B. chauvoei, but never Vibrion septique. However, eight is a small number from which to make any deductions, and we live in the hope of receiving many more samples from veterinary practitioners, from which we can examine and draw conclusions. Bosworth and Allen state that in one case out of six they have