Search results for "Fish species"
showing 7 items of 17 documents
Evaluation of a behavioural response of Mediterranean coastal fishes to novel recreational feeding situation
2011
Fish may learn to associate food with human presence through recreational hand-feeding, a popular tourist activity. The conditional learning-e. g. when an organism learns by continuous exposure to one stimulus-of different coastal fish species exposed to novel feeding situations was evaluated. The latencies of learning response to the initiation of supplementary feeding were rapid and species-specific. However differences in the learning response between different fishes decreased over time, demonstrating that associating with others might incur costs especially for small-sized species, likely due to increased competition for food. Nevertheless some other fish species did not acquire any sp…
Effects of recreational scuba diving on Mediterranean fishes: evidence of involuntary feeding?
2013
Despite a large body of literature assessing the impacts of recreational scuba diving on marine habitats, little attention has been paid to the potentially harmful effects this has on fishes. The aim of this study was the assessment of the immediate response of different fish species to divers’ activities. A decrease of fishes’ natural diffidence towards divers is shown, probably due to an enhanced availability of their prey as a result of divers’ contacts with the substrate.
The metabolism of phenol and substituted phenols in zebra fish.
1987
1. The metabolism of five phenols in zebra fish was studied after uptake from the medium. The results showed no qualitative differences to other Cyprinid fish species, only the oxidation rate seemed to be lower. 2. Phenyl glucuronide, phenyl sulphate, and quinol sulphate were identified as metabolites of phenol. 3. Identified metabolites of 2-cresol were 2-cresyl glucuronide, 2-cresyl sulphate, and 2-hydroxybenzoic acid in trace amounts. 4. Only the glucuronide and sulphate conjugates were detected as metabolites of 4-nitrophenol, 4-chlorophenol, and pentachlorophenol.
Do macrophage centres in freshwater fishes reflect the differences in water quality?
1996
Abstract Macrophage centres have been considered as a potentially useful indicator of fish health. In this histological work we tested this hypothesis with macrophage centres (MCs) in the spleen, the liver and the hematopoietic part of the kidney of two common freshwater fish species in Finland, perch ( Perca fluviatilis ) and roach ( Rutilus rutilus ). Samples were collected over 5 seasons from a system of 4 lakes providing a gradation in water quality. The mean number of MCs/mm 2 and the area covered (μm 2 /mm 2 ) by them differed between individual fish, species, organs, and lakes, with interactions amongst these factors. Hemosiderosis was recorded from the spleen and liver of both fish …
Application of machine-vision techniques to fish-quality assessment
2012
Abstract Machine vision is a non-destructive, rapid, economic, consistent and objective inspection tool and is also an evaluation technique based on image analysis and processing with a variety of applications. We review the use of machine vision and imaging technologies for fish-quality assessment. This review updates and condenses a representative selection of recent research and industrial solutions proposed in order to evaluate the general trends of machine vision and image processing in the visible range applied for inspection of fish and fish products. In order to determine freshness and composition, it is necessary to measure and to evaluate size and volume, to estimate weight, to me…
Genome sequence of Lactococcus garvieae UNIUD074, isolated in Italy from a lactococcosis outbreak.
2011
Lactococcus garvieae is the etiological agent of lactococcosis disease, affecting many cultured fish species worldwide. In addition, this bacterium is currently considered a potential zoonotic microorganism since it is known to cause several opportunistic human infections. Here we present the draft genome sequence of the L. garvieae strain UNIUD074.
Standardization of sperm motility analysis by using CASA-Mot for Atlantic salmon (Salmo salar), European eel (Anguilla anguilla) and Siberian sturgeo…
2019
[EN] It is essential to define an optimized standard method to assess the fish sperm quality to minimize the differences between the results obtained by different laboratories. Only this optimization and standardization can make them useful from academia to industry. This study presents the validation of sperm motility assessment using a CASA-Mot system for three endangered diadromous fish species: European eel (Anguilla anguilla), Atlantic salmon (Salmo salar) and Siberian sturgeon (Acipenser baerii). To attain this goal, different technical and data processing methods were tested: 1) magnification lens (×10 and ×20), 2) Spermtrack® reusable chambers (10 and 20¿¿m depth) and 3) different f…