Effect of Fixative Type and Duration on Staining Quality in Wistar Rat Testicular Tissue

Background and Objective: Fixatives and fixation protocols are critical determinants of histological staining quality, especially for sensitive tissues like the testis. However, comprehensive comparative evaluations of commonly used fixatives and fixation durations remain limited. This study aimed to assess the effects of four fixatives-Bouin’s fluid, Davidson’s fluid, formalin, and neutral buffered formalin (NBF)-at three fixation durations (48 hours, 7 days, and 4 weeks) on the staining fidelity of Wistar rat testicular tissue using different histological techniques. Materials and Methods: Testicular tissues from Wistar rats were fixed using the specified fixatives for each duration. Sections were stained with Hematoxylin and Eosin (H&E), Gordon and Sweet (G&S), and Periodic Acid-Schiff (PAS) techniques. Staining quality was evaluated based on fixation effectiveness, tissue integrity, and artefact presence. Data were analyzed using descriptive statistics and appropriate comparative tests at p<0.05. Results: Bouin’s fluid yielded superior results for H&E and G&S at 48 hours but performed poorly with PAS staining. Davidson’s fluid maintained consistent G&S staining across all durations and demonstrated high initial PAS quality. Formalin showed optimal H&E staining at 48 hours but declined with prolonged fixation. The NBF was moderately effective for short-term H&E but lacked versatility across staining methods. Conclusion: This study emphasizes the importance of selecting appropriate fixatives and fixation durations tailored to specific staining techniques. Bouin’s and Davidson’s fluids are preferable for short- and long-term use respectively, depending on the staining method. These findings can guide histologists and researchers in optimizing testicular tissue processing for enhanced diagnostic and research accuracy.