Use of the Cryostat to Prepare Slides for Trichological Analysis

The analysis of the hair cortex is rarely used for the diagnosis of mammalian species, given that the techniques used to obtain the data on this feature of the hair are often difficult to replicate. Crump and Danks (1971) demonstrated a simple method for the acquisition of transverse hair sections using razor blades. This technique was adapted from the approach used by Ford and Simmens (1959). Despite being a low-cost approach, this technique is not easy to apply, even to relatively thick hairs, such as those of pigs (Sus scrofa), and is practically impossible for finer hairs such as those of cattle, which were analyzed in the present study. This technical paper describes an easily replicable method for the analysis of the medullary cortex of mammalian guard hairs. The proposed method addresses a fundamental methodological problem for trichological analyses and permits the acquisition of cross sections that expose the cortex of the hair for analysis, thus increasing the potential of trichological analyses for a more reliable identification of mammal species.