![]() ![]() officinalis to determine the adaptability of brood-stock to artificial controlled conditions of the tanks, and the possibility/strategy to use dead feed for cuttlefish alimentation. The experiments have been carried out using adult wild-caught specimens of S. officinalis in captivity focusing specially on body patterning during alimentation and reproduction, in order to collect data regarding the behaviour of the molluscs and the possibility to consider this cephalopod among the marine organisms successfully farmable in the aquaculture industry. The present study analysed the behaviour of S. Among the Cephalopods, the scientific research focused on the common Octopus (Octopus vulgaris) and on the European Cuttlefish (Sepia officinalis). The increasing demand of fish products and the depletion of natural fish stocks rise the need to develop aquaculture and enlarge the variety of farmed species (fishes and molluscs principally). Total amount of viable nauplii was 820,550. The mean hatching rate was 30.9%-40.1% from natural insemination and 3.3% from artificial insemination. The mean rate of fertilized eggs was 52.7%-67.7% from naturally inseminated females and 7.5% from the artificially inseminated ones. In six inspections (carried out during a period of 89 days), 3,028,525 eggs were released a female released 17,500 eggs on the average (maximum was 123,000 eggs, minimum 4,340). Females with well developed gonads averaged 25.0% of the population of females at every inspection 51.3% of spawners were impregnated with spermatophores others were inseminated artificially by the method of introducing spermatophores into the thelycum. A month after eyestalk ablation the females were inspected every 7–10 days mature females were transferred to the spawning tanks. Conditions of environment and management consisted of: temperature 21☓☌ natural light and photoperiod total exchange of sea water every day feeding on mussels. A stock of 156 females, age class 1+ and F3, underwent unilateral eyestalk ablation and they were stocked with males in three plastic tanks (bottom area 14 m2) at a density of 25 individuals/m2 and a sex ratio of 1:1. To develop the shrimp-culture on a commercial basis, a convenient method for producing eggs and larvae of Penaeus japonicus was studied. Penaeus japonicus Bate is absent on the Italian coasts, but it is considered a very promising species for national aquaculture. ![]()
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