Search results for "Fish"
showing 10 items of 3164 documents
Effects of exposure to a glyphosate-based herbicide on haematological parameters, plasma biochemical indices and the microstructure of selected organ…
2022
Contamination of water environments with herbicides is a common problem nowadays. The aim of the current study was to evaluate the effects of Roundup on common carp ( Cyprinus carpio) after 1, 3 and 10 days of exposure. The used concentrations corresponded to 1 and 5 mg/l of the active ingredient (glyphosate potassium salt). The haematological analysis performed showed a decrease of the RBC count, as well as an increase of the other erythrocyte indices (Hb, MCV, MCH, MCHC). Most of these changes were dependent on the concentration and time. An increase of the WBC count and the percentage of immature neutrophils occurred, thus indicating the presence of inflammation. In the studied blood bio…
Low frequencies noise effects on behaviour of Sparus aurata juveniles
2019
Human activities in the oceans, such as marine traffic and Deep Sea Mining (DSM), are increasing in the last years (Ross 2005; Calvo et al 2016). Underwater noise in the oceans, especially at lower frequencies, is mainly produced by marine traffic and DSM could increase this noise in the next future. Marine Strategy Framework Directive promotes the achievement of a good quality environmental status and aims to monitor “continuous low frequency sound” trend in the ambient noise level within the 1/3 octave bands centred at 63 and 125 Hz. The aim of this study is to evaluate the behavioural changes of Sparus aurata juveniles exposed to a four different acoustic signals in a tank. The emitted s…
Parasite-induced aggression and impaired contest ability in a fish host
2010
Abstract Background Success of trophically transmitted parasites depends to a great extent on their ability to manipulate their intermediate hosts in a way that makes them easier prey for target hosts. Parasite-induced behavioural changes are the most spectacular and diverse examples of manipulation. Most of the studies have been focused on individual behaviour of hosts including fish. We suggest that agonistic interactions and territoriality in fish hosts may affect their vulnerability to predators and thus the transmission efficiency of trophically transmitted parasites. The parasite Diplostomum spathaceum (Trematoda) and juvenile rainbow trout, Oncorhynchus mykiss, were used to study whe…
The Riverine Organism Drift Imager: A new technology to study organism drift in rivers and streams
2023
1. Drift or downstream dispersal is a fundamental process in the life cycle of many riverine organisms. In the face of rapidly declining freshwater biodiversity, there is a need to enhance our capacity to study the drift of riverine organisms, by overcoming the limitations of traditional labour-intensive sampling methods that result in data of low temporal and spatial resolution. 2. To address this need, we developed a new technology, the Riverine Organism Drift Imager (RODI), which combines in situ imaging with machine-learning classification. This technique expands on the traditional methodology by replacing the collection cup of a drift net with a camera system that continuously images r…
Индивидуальность поведения рыб влияет на риск заражения паразитами [Personality influences risk of parasitism in fish]
2019
Influence of fish personality on infection rate is almost not studied. In the experiments on the young-of-the-year Oncorhynchus mykiss and cercariae of a trematode Diplostomum pseudospathaceum we tested the hypothesis that infection rate differs between more and less active (“bold” and “shy”) fish. Will individual differences in infection persist upon re-infection? Fish serve as a second intermediate host for this trematode. A positive correlation was found between the results of consecutive infections. Accumulation of parasites with successive infections leads to an aggregated distribution of D. pseudospathaceum among the hosts, affecting individual fitness and polymorphism in fish populat…
Anthropic impact, bioactive molecules, sustainable development, my keyword? Biodiversity!
2023
Biodiversity is my main research focus and that of my research group. We study a range of different aspects concerning biodiversity, such as the impact anthropic activities have on biodiversity and how to improve its preservation, its use as a valuable resource for the extraction of bioactive molecules, and the study of its distribution. The research group has over twenty years of experience in the study of zoology, and, more in particular, the immune and behavioural responses of aquatic invertebrates and fish. For many years, the group has observed the effects of various anthropogenic activities, such as the acoustic and chemical impacts on the physiological and behavioral responses of inv…
EFFECT OF SUBMARINE ACOUSTIC NOISE IN JUVENILE SEA BREAM (SPARUS AURATA) AND MUSSELS (MYTILUS GALLOPROVINCIALIS)
2018
The earth’ resources are running out, the population will increase and further sources will be needed. These, were found in the deep ocean. To date the mining activities (Deep Sea Mining, DSM) they have not started. One impact of DSM could be underwater noise. Considering the noise frequencies of anthropic activities in the ocean, and the European directive on underwater noise control, we stressed the animals with four acoustic 1/3 band noises around: 63 Hz, 125 Hz, 500 Hz, 1kHz. We study the effects on Sparus aurata juveniles, and on Mytilus galloprovincialis. We will analyse behavioural., molecular and biochemical responses Los recursos de la tierra se están agotando, la población aumenta…
Management Elements Proposal for Sutla Natura 2000 Site
2015
Abstract Following the accession of Croatia to the EU, a study was carried out on a Croatian Natura 2000 site which includes habitats used by the following fish species of conservation interest: Eudontomyzon vladykovi, Rhodeus sericeus amarus, Gobio uranoscopus, Romanogobio kesslerii, Barbus meridionalis, Zingel streber and Cottus gobio. Harmful effects on fish fauna were found due to: poorly-integrated water management, over-extraction of water for irrigation, fragmentation of riparian vegetation, low cooperation between environment institutions in Croatia and Slovenia, abuse of pesticides, uncontrolled waste water, sources of chemicals and heavy metals, leakage of nitrogen, habitats fragm…
Communal pair spawning behaviour of vendace (Coregonus albula) in the dark
2018
Mating in nature is rarely random, and most fish species have refined mating systems. The vendace (Coregonus albula) is a short‐lived, small‐sized, cold‐water‐adapted pelagic schooling species that is known to spawn in groups, but the actual mating system of this species, like many other group‐spawning fishes, has not been described in detail. Vendace typically spawn in the littoral or sublittoral zones of lakes in late autumn, and the hatching of larvae occurs close to icebreak in the following spring. In our large study lake, vendace larvae were caught in 93% of 1,149 random sampling locations lake‐wide. We examined the courtship and mating of vendace under experimental conditions by noni…
Sulfate sensitivity of aquatic organism in soft freshwaters explored by toxicity tests and species sensitivity distribution
2023
Elevated concentrations of sulfate in waterways are observed due to various anthropogenic activities. Elevated levels of sulfate can have harmful effects on aquatic life in freshwaters: sulfate can cause osmotic stress or specific ion toxicity in aquatic organisms, especially in soft waters where Ca2+ and Mg2+ concentrations are low. Formerly, chronic toxicity test data in soft water have been scarce. The chronic and acute sulfate toxicity tests conducted with aquatic organisms from 10 families across various trophic levels in this study multiplied the number of tests conducted in soft freshwater conditions and enabled derivation of the species sensitivity distribution (SSD) and sulfate haz…