Simple method for the perfusion-fixation of adult bovine brain

It is widely accepted that the vascular perfusion of a tissue leads to its optimal fixation for ultrastructural examination, but the technique has been applied with little success in large animals such as cattle. This paper describes a simple and highly reproducible method for the perfusion-fixation of adult bovine brain. The carotid arteries are cannulated and the perfusate is introduced by means of a peristaltic pump. The inclusion of toluidine blue in the fixative makes it possible to assess the success of the technique, and prevents the costly and time-consuming processing of material which is suboptimally fixed. The method is potentially valuable for the examination of a wide range of neurological conditions in large domestic animals at an ultrastructural level in optimally fixed material.