Growth performance and RNA/DNA ratio of noble crayfish (Astacus astacus) and narrow‐clawed crayfish (Pontastacus leptodactylus) fed fish waste diets

Freshwater crayfish Astacus leptodactylus (Eschscholtz, 1823) accumulates and depurates copper.

Cu accumulation and depuration in various tissues of the crayfish Astacus leptodactylus was investigated. Adult specimens were exposed to 0.5, 2.5 and 5.0 mg Cu/L under static conditions for three weeks. At the end of the 3rd week the specimens were divided into three groups and left in dechlorinated water for either 1, 2 or 3 weeks for depuration. After 7, 14 and 21 days, four crayfish from ea...

Ontogeny of osmoregulation in the crayfish Astacus leptodactylus.

Osmoregulation was studied during the postembryonic development of Astacus leptodactylus Eschscholtz 1823 in juvenile stages 1-8 and in adults. Juveniles hatch and later stages develop in freshwater or in moderately saline waters. The time of acclimation from freshwater to a saline medium increased from early juveniles to adults. At all stages, it was longer than in comparable stages of marine ...

Growth, Molting and Survival Response of Juvenile Narrow Clawed Crayfish, Astacus leptodactylus, Fed Two Sources of Dietary Oils

 The influence of five pure diets of isonitrogenous and isoenergic with different ratios of Clupeidae fish oil (F) and soybean oil (S) on growth, molting and survival of narrow-clawed crayfish, Astacus leptodactylus, was evaluated during an 8-weeks trial. As soybean oil replaced with fish oil in each treatment, gently. Test diets were inclusive F0/S100, F30/S70, F50/S50, F70/S30 and F100/S0 fis...

Evaluation of different dietary protein and energy levels on growth performance and body composition of narrow clawed crayfish (Astacus leptodactylus)

Growth, Molting and Survival Response of Juvenile Narrow Clawed Crayfish, Astacus leptodactylus, Fed Two Sources of Dietary Oils

 The influence of five pure diets of isonitrogenous and isoenergic with different ratios of Clupeidae fish oil (F) and soybean oil (S) on growth, molting and survival of narrow-clawed crayfish, Astacus leptodactylus, was evaluated during an 8-weeks trial. As soybean oil replaced with fish oil in each treatment, gently. Test diets were inclusive F0/S100, F30/S70, F50/S50, F70/S30 and F100/S0 fis...