Report on an inquiry into the nature, causes, and prevention of splenic fever, quarter-evil, and allied diseases : made at the Brown Institution / by W.S. Greenfield.

  • Greenfield, W. S. (William Smith), 1846-1919.
Date:
1880
Catalogue details

Licence: Public Domain Mark

Credit: Report on an inquiry into the nature, causes, and prevention of splenic fever, quarter-evil, and allied diseases : made at the Brown Institution / by W.S. Greenfield. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    enormous quantities in the blood and certain of the tissues of animals dying of the disease. It has been shown by repeated experiment that it may be artificially cultivated outside the living body, under conditions suitable to its growth and pro- pagation ; that it nevertheless retains its virulent property, which may be transmitted from generation to generation, so that a far distant progeny of the bacillus first grown from the blood of the living animal, if introduced into the system of another living animal, gives rise to all the phenomena of the disease. Moreover, the disease is readily communicable to a large number of known animals, rodents being especially suscep- tible, guinea-pigs and mice being amongst the most easily inoculated. In transmitting the disease through rodents to bovine ani- mals, two distinct methods may be employed; the one of direct inoculation, the other of inoculation with the cultivated virus. The direct method, that employed by Mr. Duguid in his experiments, consists in inoculating the bovine animal with the blood or spleen of a guinea-pig which has died of the disease produced either by inoculating from a cow, or from one of a series of which the first was inoculated from a cow. That is, if guinea-pig A is inoculated from a cow, B from A, C from B, D from C, and then a cow direct from D, it would be an ex- ample of direct inoculation. Or it might be inoculated direct from A or B or C. Dried blood, if properly secured, retains in parts its infective power for a considerable time, so that this process of transmission may have been carried over some months. The “ cultivation ” or indirect method proceeds on the basis of the fact already indicated, that the poison (the Bacillus anthracis) may be artificially grown in a cultivating fluid in successive generations, and that the last generation may then be inoculated and produce the symptoms and fatal result of the disease. Seeing that the object of my experiments was to inoculate bovine animals with a virus modified by its transmission through the guinea-pig, it may appear that it would be de- sirable, in order to have the full effect of such modification, either to inoculate directly from the guinea-pig or from a culti- vation not far removed from it. But there would be many practical advantages, if it were found that, having once trans- mitted the virus through one guinea-pig or a series of them, its modified property were subsequently maintained in the artificial cultivations. 1 have therefore kept this in view, and have