Abstract
Since Seibert 1 extended the work of Hort and Penfold 2 on the occurrence of pyrogen in distilled waters, various tests for the detection of this substance have been proposed. A chemical test which has been in use depends upon the decoloration of potassium permanganate added to the solution to be tested. But this test is unsatisfactory because, on the one hand, it can be used only in solutions in which medicaments do not decolorize this oxidizing agent and, on the other hand, it is not sensitive enough to detect the minute amount of pyrogen necessary to cause even a severe physiologic response. Resort must therefore be made to biologic test.
Test Animals. Seibert in her work used the rabbit as the test animal. This practice has been followed by other workers, among them Banks, 3 Lees and Levvy, 4 and by commercial houses in routine tests of infusion fluids. Sabin and Wallace 5 used the dog in their study of the chill-producing substance in pneumonia serum. While in all our published work 6 we have used the dog, we have had just as extensive experience with the rabbit. It is pertinent here to discuss the advantages and disadvantages of these 2 test animals.
The rabbit has a labile thermoregulatory mechanism and frequently gives false positive tests. Because of this, a negative test is more significant than a positive one in the rabbit. These animals must be conditioned to handling and to the taking of rectal temperatures for several days before they can be used, as untrained rabbits exhibit a rather bizarre temperature pattern. Feeding is followed by a mild pyrexia which lasts several hours and therefore they should not be fed for at least 6 hours before use as test animals.
Get full access to this article
View all access options for this article.