Sturgeon stress reactions in aquaculture

One of the main practical problems in aquaculture is the stress influence on reproduction. General management practices ( capture, handling, transportation) in fish hatcheries induced stress responses. Serum cortisol, testosterone and glucose concentrations were measured in stellate sturgeon ( Acipenser stellatus, Pallas) and Russian sturgeon ( A. gueldenstaedtii, Brandt) under stress conditions: (i) during capture; (ii) forced swimming and (iii) air exposure. The results suggest that the increased cortisol and glucose level noted indicate stress responses. The authors suggest that in general the short-term hatchery practices utilized do not lead to deterioration of gamete quality in sturgeon breeders. However, prolonged hatchery procedures at high spawning temperatures and high loading densities may negatively affect reproduction.