Search results for "Fish"

A simple experimental setup for testing saltwater preference

2011

Mineral content of eggs

2015

The success of crayfish stocking in a dredged river with and without artificial shelter increase

1997

Abstract The success of crayfish ( Astacus astacus L.) stocking in a heavily dredged river in Finland was compared between sections with and without artificial shelter. The materials used for creating shelter were a) broken rock and, b) ceramic drain pipes and perforated bricks. Group-marked crayfish (mean carapace length 42.6 mm) were released into the sections and test trappings conducted one year later. The highest crayfish densities were found in the broken rock sections. The reasons for the observed crayfish densities are discussed. No significant differences in growth between groups were detected. Migrations in the range of 2.5 km in one year were recorded.

Growth and food utilisation of rainbow trout (Oncorhynchus mykiss) fed low-fat herring and dry diets enriched with fish oil

1998

Two-year-old rainbow trout (initial weight 695 g) were fed for 15 weeks low-fat Baltic herring diets either with or without lipid enrichment. For comparison, similar groups of trout were fed dry pellets with and without top-dressing with fish oil. Inclusion of lipid increased growth rate in a similar manner for both types of diets. For the herring-based diet, increased lipid resulted in increased dry matter consumption but for the dry diet, feed efficiency (dry weight growth per dry weight food consumption) was improved by channelling more nutrients to lipid deposition. If compared within a stated lipid level, fish fed the herring-based diets grew at a slower rate than fish fed the dry diet…

First record of Vibrio vulnificus biotype 2 from diseased European eel, Anguilla anguilla L.

1991

Dikerogammarus villosus (Crustacea : Amphipoda): another invasive species in Lake Geneva

2004

According to field observations performed in 2002 and 2003, the amphipod species Dikerogammarus villosus (Sowinsky, 1894) is now well established in Lake Geneva. The author predicts that this and future invasions by D. villosus will have serious effects on freshwater ecosystems.

Trawl mesh selectivity and body engagement pattern in the red shrimpAristaeomorpha foliacea(Risso, 1827) (Crustacea: Decapoda)

1998

The paper presents selectivity data and utilizes an elliptic surface index (maximum height and width of the folded body), in order to explain the selectivity differences between sexes and to investigate the body engagement pattern of the red shrimp Aristaeomorpha foliacea. The results show that males are retained more, with significant differences, and demonstrates a previously unknown morphological difference between sexes (folded males are significantly higher than females of the same carapace length, while the latter are larger, but not significantly, than males of similar size). Nevertheless, in practice the overall escapement rate should not change dramatically with sex, since the resu…

Impact of salmon farming on Atlantic cod spatio-temporal reproductive dynamics

2021

Salmon farming in marine net pens is a major activity in many temperate regions. This industry may affect coastal ecosystems in several ways, such as with waste pollution and parasite spillover. Less is known about the extent to which salmon farming disrupts the use of inshore spawning grounds by wild fish, such as the Atlantic cod Gadus morhua. Acoustic telemetry was therefore used to explore cod space use during the spawning season in a coastal region in mid-Norway with multiple salmon farms. Acoustic receivers were placed in clusters at 5 known cod spawning grounds and 6 nearby salmon farms. Data from 481 adult cod caught at the spawning grounds during 2017-2019 and equipped with acousti…

Fast environmental impact assessment through ICP-MS: application to bivalves from a tropical estuary (Pina Bay, Recife, Brazil)

2002

Sea Urchin Granuloma

2005

Sea urchin granuloma is a chronic focal response to the puncture of sea urchin spines, induced by the permanence of prickle remnants in the wound. Until recent years, it was thought to represent a foreign body reaction but, following the description, in 2001, of its several histologic forms, the spectrum of its likely pathogenetic mechanisms has widened to include the immune responses to different non-self antigens. Depending on individual reactivity, in most cases, a limited number of granulomas is observed, however numerous the punctures may be. We report a case with more than 200 lesions and a tuberculoid histologic pattern, indicative of an immune reaction.