Association of Americium-241 with adenochromes in the branchial hearts of the cephalopod Octopus vulgaris

An autoradiographic study of the subcellular localization of 241 Am in the branchial hearts of the cephalopod Octopus vulgaris was carried out after uptake from sea water. It was demonstrated that the radionuclide is closely associated with granular pigment concretions or adenochromes occurring in the cells of the branchial hearts of the octopus

High concentrations of transuranics and natural radioactive elements in the branchial hearts of the cephalopod Octopus vulgaris

Data are reported which show elevated levels of plutonium and americium in the branchial hearts of the common cephalopod Octopus vulgaris. These levels were verified in both a laboratory experiment and in environmental samples. At the same time data for certain naturally-occurring radioactive isotopes of thorium, polonium and lead are given for comparison. Attention is directed to the potential of these small organs as monitors of transuranics and, probably, certain other elements in the marine environment

Effects of various diets on the nutritional value of Artemia sp. as food for the prawn Penaeus monodon

The nutritional value of Artemia sp. as food for marine fish and crustacean larvae has been linked to the level of its polyunsaturated fatty acid (PUFA) content. Experiments in August 1984 were conducted to determine the effects of various artificial diets and algae on fatty acid composition of PUFA-deficient Artemia sp. (Utah GSL strain) and their resulting value as food for postlarvae of the prawn Penaeus monodon (Fabricius). Nauplii of the brine shrimp were grown on extracts of corn, copra, soybean and rice bran containing precursors (C18) to long-chain PUFA and also on algal species containing different levels of long-chain PUFA (C20). The nauplii were then used as food for P. monodon postlarvae. The results revealed that absence of C20 polyunsaturates from the feeds and their presence in the algae were reflected in the polyunsaturated fatty acid content of the tissues of Artemia sp. When fed with brine shrimp fed on algae, P. monodon displayed better postlarval survival and significantly higher growth; related to the content of polyunsaturated fatty acids in Artemia sp. A practical feeding approach in prawn hatcheries would be to grow Artemia sp. on a cheap diet such as rice bran, and then to enhance its nutritional value with a diet high in PUFA prior to harvesting, in order to improve hatchery production