An evaluation of the effects of immersion fixatives on rat testis

Routinely used fixatives cause tissue damage in fragile organs like testis. The present study aims to evaluate the testicular damage induced by the fixatives. Four different fixatives, Neutral buffered formalin (NBF), 10% formalin, Bouin's fluid and NBF + Bouin's fluid were selected to fix the testis Rats (n = 5, each group) were sacrified, testes were removed, fixe, weighed and processed for paraffin embedding. Five micron thick sections were obtained, stained with haematoxylin and eosin. The testis weight/100 g body weight, diameter of testis/g testis, seminiferous tubular diameter, peripheral indentations and extent of sloughing of epithelium were measured. Bouin's fluid maintained the integrity of epithelium but caused maximum shrinkage whereas NBF caused least shrinkage with disruption of epithelial harmony. Combination of NBF and Bouin's fluid showed minimum epithelial destruction and less shrinkage whereas 10% formalin caused both shrinkage and extensive epithelial damage. These findings that conclude Bouin's fluid is the best fixative for qualitative analysis and NBF + Bouin's secondary to Bouin'and is mainly for quantitative analysis.