ABSTRACT
The laboratory rat is widely used in biomedical research. Despite this fact, few studies have been published that have correlated longevity and the age-associated patterns of spontaneous neoplastic and nonneoplastic lesions in rats. The normal age-associated pathology of aging rats must also be defined. Several investigators have described or reviewed spontaneous nonneoplastic lesions of rats. Each rat strain seems to develop its own characteristic set of lesions. Some have a high incidence of radiculoneuropathy, while others have a very low incidence. Many of the studies included rats that were killed before the end of their natural life span, and there are few published comparisons of the lesions of rats that died spontaneously compared to those killed at the same age. Specific husbandry conditions have been shown to alter longevity and pathologic findings in rats. The chapter also presents an overview of key concepts discused in this book.
