Abstract
Leydig cells have been found to be either unidentifiable or at apparent low numbers during routine histologic examination of bowhead whale testes. Therefore, formalin-fixed, paraffin-embedded testicular tissues from 14 bowhead whales were retrospectively examined to determine if immunohistochemical staining could aid in identification of Sertoli and Leydig cells. Multiple intratesticular samples were examined when available. Sertoli and Leydig cells were differentiated using inhibin and calretinin stains. Significant whale length and seasonal differences were not found; however, a trend toward increased staining intensity was noted for autumn harvested whales.