Abstract

Ten mature male broodstocks of Heterobranchus longifilis, Red mud catfish were purchased from a reputable farm, Arewa in Zaria for the research. A two-year-old mature male broodstock weighing 0.5kg among the ten mature male broodstocks was discovered to be a monorchid. This was observed when the broodstock was euthanized and a mid-ventral line incision of about 2-3 cm long was made using scalpel blade in order to explore its abdominal cavity for testicular exteriorization. Upon abdominal exploration, only the right testis was present but the right testis was completely absent without remnant. The left testis present was observed to be twisted in the middle along its vertical axis. The morphometric and milt parameters of the right testis present were determined as: testicular length (4.2 cm), testicular weight (1.05 g), milt volume (0.12ml), sperm motility (75%) and sperm concentration (377 x 106/ ml).

Keywords: Broodstocks, Exteriorization, Monorchidism, Morphometric and Testis

Key words: Broodstocks, exteriorization, monorchid, morphometric and testis