Laboratory rat and mouse colonies: some implications for biomedical research.

Abstract

The health of laboratory rodents has a significant bearing on experimental results; the use of healthy animal stock allows experiments to be completed without the complication of premature mortality. The first part of the report describes the implementation and management of germ-free and specific-pathogen-free rodent facilities at the AAEC Research Establishment. The second part is a comparative histological study of the lungs of germ-free rats and those reared conventionally. In animals autopsied over the period of 2 to 18 months it was found that there was little or no pathological change in the lungs of the germ-free rats whereas a progressive and serious deterioration was observed in the lungs of conventionally reared rats examined at similar time intervals. Some barrier-housed ex germ-free rats were similarly examined and found to be free from chronic respiratory disease.