Sea Water Enhances Formalin Fixation of Sheep Tissues: Comparative Study with Distilled Water

This study investigated the effect of seawater as a diluent in formalin- and ethanol-based fixation solutions on the histological preservation of sheep tissues. Liver, heart, and spleen samples obtained from 40 sheep were fixed using six different solutions prepared with distilled water, seawater, or their combinations. Tissue samples (approximately 3 mm in thickness) were fixed for 24 hours at room temperature, followed by routine histological processing, sectioning at 4 µm, and hematoxylin and eosin (H&E) staining. Histological preservation was evaluated using a semi-quantitative scoring system, and the resulting scores were analyzed using appropriate statistical methods. Formalin-based fixatives demonstrated superior structural preservation compared to ethanol-based solutions. Among the formalin groups, seawater-containing solutions yielded the highest histological scores across all tissues. In contrast, ethanol-fixed tissues exhibited reduced structural integrity and lower preservation scores. These findings suggest that seawater can enhance the efficiency of formalin-based fixation and improve histological outcomes, offering a simple and cost-effective alternative to conventional diluents.