Showing papers in "Aquaculture in 1986"

TL;DR: It is suggested that the lipid index may be used to document visually the lipid content in individual bivalve larvae as an indicator of physiological condition and potential for successful metamorphosis.

TL;DR: More research is needed to better understand both the phenotypic and genetic relationships between growth, survival and fecundity traits and age at maturity in fish and shellfish.

TL;DR: The marine calanoid copepod Acartia tonsa has been continuously cultivated in the laboratory at the Danish Institute for Fisheries and Marine Research for over 70 generations and a description of the cultivation procedures is presented.

TL;DR: The data suggest that there is a minimum, size-related, threshold lipid level in eggs necessary for optimal survival through the non-feeding embryonic stages; but environmental or genetic factors other than egg lipid content are responsible for a considerable fraction of the mortality during this period.

TL;DR: It is concluded that in the later stages of maturation, the quality of the meat deteriorates and the odour and flavour became much less pronounced, and the texture became watery and tough.

TL;DR: Red drum grew best when fed to satiation on a 44% protein diet at dietary energy levels of 1.72 × 10 4 kJ/g, and higher levels of dietary carbohydrate and lipid were associated with an increased hepatosomatic index.

TL;DR: Details of the techniques developed are presented and the problems of applying genetic methods to commercial aquaculture are considered, which are suitable for use on technically unsophisticated farms, require no specialized equipment and are aesthetically acceptable to the consumer.

TL;DR: The chromosome set manipulation techniques of induced polyploidy, gynogenesis and androgenesis are likely to have significant applications in aquaculture and may be useful for producing individuals with increased heterozygosity.

TL;DR: Susceptibility of a specific spinal deformity, first observed in 2 1 2 - year-old Atlantic salmon, was found to be genetically heritable and the reason for the deformity could not be determined.

TL;DR: It is demonstrated that an extensive or semi-intensive cultivation of the omnivorous serrasalmids belonging to the genus Colossoma can make an important contribution to the nutrition of the rural population.

TL;DR: The data suggest that transgenic trout can be routinely obtained in large proportions and that foreign DNA was most likely integrated in the trout genome.

TL;DR: Weight gain was significantly higher for those fish fed diets containing 43 or 52% protein and 24% lipid, than fish fed all other diets, and increasing dietary protein tended to result in an increase in gross conversion efficiency of lipid at both dietary lipid levels within each feeding rate.

TL;DR: Diet containing crystalline amino acids gave survival rates and growth indices equal to or higher than the control group receiving live food, indicating that prawn larvae are probably able to utilize an amino acid mixture as a partial protein substitute in contrast to juvenile prawns which lack this ability.

TL;DR: The fatty acid composition of the dietary fat had a strong influence on the composition of liver triglycerides, which constitute the main fat depot in cod, and also affected the compositionof polar lipid fatty acids in liver and muscle.

TL;DR: Channel catfish in aquaria were fed diets containing 0, 2, 4, 6, 8 or 10 mg of supplemental copper/kg diet for 13 weeks, and the minimum dietary copper requirement of channel catfish was determined to be approximately 5 mg of total copper/ kg diet.

TL;DR: A comparison of growth performance of each of the sexes when raised alone and when raised in mixed populations showed that whereas females are strongly affected by the presence of males, resulting in growth inhibition, males are hardly influenced byThe findings of this study call for intensive efforts in research directed towards the controlled establishment of prawn monosex populations.

TL;DR: The results support previous research that showed that the carnivorous P. esculentus uses muscle protein preferentially as a source of energy during starvation, indicating that protein is virtually the only energy substrate under these conditions.

TL;DR: Genetic analysis of the founder stock and five subsequent hatchery generations revealed a constant reduction in levels of allozyme polymorphism, which pointed out the importance of a careful check of the number of spawners actually contributing to each reproductive cycle.

TL;DR: Growth potential of the spat was dependent on the amount of lipid reserves in the larvae at the time of settlement as well as on post-larval diet, and faster growing spat accumulated greater lipid reserves, which were, in turn, associated with relatively higher growth rates when spat were transferred to the sea.

TL;DR: The digestibility of most of these feedstuffs was less in the anterior than in the posterior intestine, and tended to be lower in seawater than in freshwater, which may in part be due to food motility changes necessitated by alterations in osmoregulatory processes when fish are in seaw water.

TL;DR: It is suggested that ascorbic acid supplementation of broodstock diets results in some transfer of the vitamin via the eggs to newly hatched fry resulting in some amelioration of ascorBic acid deficiency during the early stages of life.

TL;DR: The present analyses did not reveal colour differences between farmed and wild salmon except for those caused by differences in carotenoid concentration.

TL;DR: The results indicate that the gross energy content of feed and faeces can be determined most accurately by combustion, and calculation from chemical composition will underestimate dietary and faepal gross energycontent.

TL;DR: A linear relationship between growth and carotenoid level was found for growth rates below 150 g/65 days and the pylorus seems to be the site for absorption of astaxanthin.

TL;DR: Stocking of ponds with planktivorous carps in polyculture with channel catfish and a hybrid reduced the density of zooplankton when compared to controls, though the mechanism of suppression may be different.

TL;DR: The dietary iron requirement of fingerling channel catfish was determined to be not more than 30 mg Fe/kg diet, which was found to be adequate to maintain optimum hematological values.

TL;DR: Survival of the prawn was higher with diets containing casein and gelatin as the protein source than with those containingcasein as the sole source of protein.

TL;DR: Growth and gonadal development of triploid and diploid coho salmon in three treatment groups in fresh and seawater from the time of smoltification at 18 months to the onset of sexual maturity at 30 months were compared.

TL;DR: Epinephrine-induction appears to have no negative effects on survival or development, with spat grown for periods of 12 months appearing normal.

TL;DR: The results indicate that the requirements of the African catfish with respect to crude protein and metabolizable energy are comparable to those of other omnivorous fish species, while younger fish utilize their feed with a higher efficiency than older fish.