Optimization of stem cell extraction from blue catfish (Ictalurus furcatus) to produce alloxenogenic catfish: Effects of body size, sex steroids, and seasonality

Abstract

Xenogenesis has been identified as an innovative technology for hybrid catfish (♀ channel catfish, Ictalurus punctatus × ♂ blue catfish, I.furcatus) embryo production. Currently, donor cells are collected from randomly selected immature fish without having prior knowledge regarding the best donor size. Immature blue catfish males with a total length (TL) of 38.1 cm and total weight (TW) of 400.2 g, and immature blue catfish females with a TL of 31.2 cm and TW of 410.1 g were the best sizes to yield the maximum number of spermatogonial stem cells (SSCs) and oogonial stem cells (OSCs), respectively. In addition, testosterone (T) and 11-ketotestosterone (11-KT) levels were identified as reliable biomarkers to predict the maximum number of SSCs, which were 50.9 pg/mL and 44.7 pg/mL, respectively. The potential use of mature blue catfish males and females as alternative donors was evaluated. However, stem cell extraction was time consuming and labor intensive, thus the smaller, immature fish were a better source of stem cells.

Key words: xenogenesis; blue catfish; androgen; stem cell; seasonal variation; gonodosomatic index