ABSTRACT
The biological fixatives have an important role in the final histology quality. In veterinary, routine skin biopsy is a common procedure and the choice of fixative is essential for the final result. The most common fixative is Formalin, even though it is toxic, carcinogenic, and has low and slow penetration. Still, there isn't a fixer which can replace the qualities of formalin. The aim of this study was to evaluate qualitatively the preservation of the histological features of dog skin using different tissue fixative embedded in paraffin, sectioned and stained with hematoxylin - eosin. We used a 4 mm punch pen to collect ear skin samples in six dog cadavers. After collection, the tissues were fixed in: (1) Bouin for 6 hours; (2) Carnoy for 4 hours; (3) 10% buffered formaldehyde for 24 hours, all under refrigeration (4 ° C). The tissues were then processed, sectioned and stained with hematoxylin and eosin. The slides were evaluated blindly by four different pathologists who considered the qualitative aspects below: (1) quality of coloring; (2) preservation of the histological characteristics; (3) preservation of cytoplasmic boundaries using a Likert scale score for each blade. The fixative with the highest mean score on all items was buffered formalin with 3.76 points followed by Bouin (3.39) and Carnoy (2.52). Formaldehyde can bring health a risk of professional routine handling, so it is necessary to search for a biological fixative with the same qualities being less harmful to health.
Keywords:
dog; formaline; Bouin; Carnoy; histology
