Fixatives and methods of fixation in selected tissues of the laboratory rat.

The histologic appearances of tissues fixed by immersion and perfusion were compared, as well as the effects of these different fixatives: 10% neutral buffered formalin, Carnoy's fluid, and Bouin's fluid. Intravascular perfusion provided better tissue preservation than fixation by immersion. The quality of preservation by neutral buffered formalin was equal to that of Carnoy's fluid and Bouin's fluid, but the overall staining quality of the latter two was judged to be superior.