ORIGINAL PAPER Histology of salmonid testes

• Main Authors: During Maturation, Katarzyna Dziewulska, Józef Domagała
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2002
• Subjects: Salmo salar
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.641.4859; http://www.repbiol.pan.olsztyn.pl/docs/pdfs/repbiol_vol3_num1_page47.pdf

The commonly applied classifi cation systems of fi sh gonad maturity di-vide the maturation process into certain stages. However, the scales do not entirely refl ect the continuity of the maturation process. Based on light microscope observations, the paper describes a comprehensive pattern of testicular transformations during maturation. The study was carried out on precocious underyearling and 1-year-old males of sea trout (Salmo trutta m. trutta L.), 1-year-old males of salmon (Salmo salar L.), and males of brown trout (Salmo trutta m. fario L.) aged from 7 months to 4 years. A total of 821 gonads collected during all seasons of the year were examined. The fi sh were fi xed in Bouin’s fl uid. Histological slides of the mid-part of the gonad were made using the standard paraffi n technique. The 3-6 µm sections were stained with Heidenhain haematoxylin. Histological changes of testes during maturation were similar in the three species studied. Im-mature and resting gonads contained type A spermatogonia in lobules only. The appearance of cystic structures containing type B spermatogonia in the lobules signalled the beginning of the sexual cycle in male gonads. Type B spermatogonia underwent synchronous mitotic divisions resulting in an increase in the total number of spermatogonia. As the spermatogenesis