Abstract
An attempt was made to reestablish the virus-like agent associated with rat pneumonia by the nasal instillation of the infectious material into supposedly normal young rats from the selected Princeton colony. The incidence of the pneumonia in these animals after the injection of suspensions of pneumonic lungs from either rats or mice was not significantly greater than the incidence under natural conditions. In attempting to account for the refractory state of the immature rats it was found that the agent was widely dispersed through the breeding colony at an early age. Detailed tests of many litters indicated that the agent was acquired shortly after birth by way of the upper air passages as the result of maternal contact. In most instances it was so well tolerated by young rats during the suckling period and for several months thereafter that its presence was recognized only by nasal transfer to mice. There is every indication that the rate of infection of rats in the breeding colony approaches 100 per cent by the time the animals are old enough to be used experimentally.
Full Text
The Full Text of this article is available as a PDF (497.2 KB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Nelson J. B., Gowen J. W. THE ESTABLISHMENT OF AN ALBINO RAT COLONY FREE FROM MIDDLE EAR DISEASE. J Exp Med. 1931 Oct 31;54(5):629–636. doi: 10.1084/jem.54.5.629. [DOI] [PMC free article] [PubMed] [Google Scholar]