983 resultados para New cave fish


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The Wapsipinicon River, affectionately known as the “Wapsi,” flows nearly 300 miles through northeastern Iowa to the Mississippi. Strung throughout its drainage basin is a series of dams that are highly valued by their communities as places of recreation and scenic beauty. The Wapsipinicon has long had a reputation as a fishing stream, known for catfish, northern pike, carp, sunfish, walleye, and smallmouth bass. It is not uncommon to find anglers of all ages gathered at one of the Wapsipinicon’s dams to enjoy a day of fishing and possibly take home a prize catch. As time passes, however, a dam may outlive its original function, impede fish passage, and pose a safety hazard. But the idea of demolishing an outdated dam often rallies the community in an attempt to preserve the landmark.

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The description of all the species present in nature is a vast task to be fulfilled by using the classical approach of morphological description of the organisms. In recent years, the traditional taxonomy, based primarily on identification keys of species, has shown a number of limitations in the use of the distinctive features in many animal taxa and inconsistencies with the genetic data. Furthermore, the increasing need to get a true estimate of biodiversity has led Zoological Taxonomy to seek new approaches and methodologies to support the traditional methods. The classification procedure has added modern criteriasuch as the evolutionary relationships and the genetic, biochemical and morphological characteristics of the organisms.Until now the Linnean binomial was the only abbreviated code associated with the description of the morphology of a species. The new technologies aim to achieve a short nucleotide sequence of the DNA to be used as an unique and solely label for a particular species, a specific genetic barcode. For both morphological and genetic approaches, skills and experience are required. Taxonomy is one of zoological disciplines that has been benefited from the achievements reached by modern molecular biotechnology. Using a molecular approach it is possible to identify cryptic species, to establish a family relationship between species and their membership of taxonomic categories or to reconstruct the evolutionary history of a taxon.

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Senegalese sole (Solea senegalensis) has been considered since the 1990´s to be a promising flatfish species for diversifying European marine aquaculture. However, pathogen outbreaks leading to high mortality rates can impair Senegalese sole commercial production at the weaning phase. Different approaches have been shown to improve fish immunocompetence; with this in mind the objective of the work described herein was to determine whether increased levels of dietary vitamin A (VA) improve the immune response in early juveniles of Senegalese sole. For this purpose, Senegalese sole were reared and fed with Artemia metanauplii containing increased levels of VA (37,000; 44,666; 82,666 and 203,000 total VA IU Kg-1) from 6 to 60 days post-hatch (early juvenile stage). After an induced bacterial infection with a 50 % lethal dose of Photobacterium damselae subsp. damselae, survival rate, as well as underlying gene expression of specific immune markers (C1inh, C3, C9, Lgals1, Hamp, LysC, Prdx1, Steap4 and Transf) were evaluated. Results showed that fish fed higher doses of dietary VA were more resistant to the bacterial challenge. The lower mortality was found to be related with differential expression of genes involved in the complement system and iron availability. We suggest that feeding metamorphosed Senegalese sole with 203,000 total VA IU Kg-1 might be an effective, inexpensive and environmentally friendly method to improve Senegalese sole immunocompetence, thereby improving survival of juveniles and reducing economic losses.

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Since 2005, harmonized catch assessment surveys (CASs) have been implemented on Lake Victoria in the three riparian countries Uganda, Kenya, and Tanzania to monitor the commercial fish stocks and provide their management advice. The regionally harmonized standard operating procedures for CASs have not been wholly followed due to logistical difficulties. Yet the new approaches adopted have not been documented. This study investigated the alternative approaches used to estimate fish catches on the lake with the aim of determining the most reliable one for providing management advice and also the effect of current sampling routine on the precision of catch estimates provided. The study found the currently used lake-wide approach less reliable and more biased in providing catch estimates compared to the district based approach. Noticeable differences were detected in catch estimates between different months of the year. The study recommends future analyses of CAS data collected on the lake to follow the district based approach. Future CASs should also consider seasonal variations in the sampling design by providing for replication of sampling. The SOPs need updating to document the procedures that deviate from the original sampling design.

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In order to evaluating Streptoccocus iniae pathogenicity recovered from trout in Fars province a total number of 400 healthy (15-20g) fingerling fish specimens which were kept in 1000 liters ponds and after spending compatibility (adaptation) period in new environment and desired condition as aspect of temperature, pH, food and density relative to accomplish disease experiments in interamusclar injection method with 3 × 10 3 , 3 × 10 4, 3 × 10 5, 3 × 10 6 ,3 × 10 7 bacterium cell dilutions per each fish, interaperitonal method with 2 × 10 3 , 2 × 10 4, 2 × 10 5, 2 × 10 6 ,2 × 10 7 dilutions of bacterium cell and in water bath method with 2 × 10 3 , 2 × 10 4, 2 × 10 5, 2 × 10 6 2 × 107 dilutions in 20 degree centigrade temperature were used. Control groups according to above (mentioned) method with 0.1cc sterile physiological serum per each fish were injected. Clinical and autopsy signs that observed in injected groups were includes: body darkness, swelling of abdomen, exophthalmy sometime with eye ocular haemorrhagy, anal (rectal) prolaps, blood congestion and petechia in muscles and congestion and haemorrhagy in intestines. Infectious results in interamusclar injection shown that, mortality 22 hours after injection begans and in 3 × 107 cells dilution per each fish 30 hours pass the injection was reached above 50 percent, so that the amount of LD50/ 30h in 3 × 10 7 cells per each fish was estimated. In interaperitonal injection method was shown those 20 hours after injection mortality begins and up to maximum 80 hours after continued and 32 hours after injection in 2 × 10 7 cells dilution mortality was reached above 50 percent, so that LD50 /32 hour in 2 × 10 7 cell dilution per each fish estimated. In water bath method even after sparing 15 days mortality had been too low which indicating long process of disease. By microscopic study of tissues, dilatation of bowman capsule, shrinkage of glomerols, increasing of melano macrophage centers, degeneration, necrosis of urine tubules in kidney tissue, dilatation of sinusoids, congestion of hepatic vessels, increasing of melanoma macrophages and hepatocite vacuolization in liver tissue, spleen congestion, heart pericardit, ocular haemorrhagy, congestion, edema and separating of basement membrane from gill secondary lamellae can be referred.

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Conservation of the seven lagoons of the Palavas complex (southern France) has been severely impaired by nutrient over-enrichment during at least four decades. The effluents of the Montpellier wastewater treatment plant (WWTP) represented the main nutrient input. To improve the water quality of these lagoons, this WWTP was renovated and upgraded and, since the end of 2005, its effluents have been discharged 11 km offshore into the Mediterranean (total investment €150 M). Possibilities of ecosystem restoration as part of a conservation programme were explored by a focus group of experts. Their tasks were: (i) to evaluate the impact of the reduction of the nutrient input; (ii) if necessary, to design additional measures for an active restoration programme; and (iii) to predict ecosystem trajectories for the different cases. Extension of Magnoliophyta meadows can be taken as a proxy for ecosystem restoration as they favour the increase of several fish (seahorse) and bird (ducks, swans, herons) species, albeit they represent a trade-off for greater flamingos. Additional measures for active ecosystem restoration were only recommended for the most impaired lagoon Méjean, while the least impaired lagoon Ingril is already on a trajectory of spontaneous recovery. A multiple contingent valuation considering four different management options for the Méjean lagoon was used in a pilot study based on face-to-face interviews with 159 respondents. Three levels of ecosystem restoration were expressed in terms of recovery of Magnoliophyta meadows, including their impact on emblematic fish and avifauna. These were combined with different options for access (status quo, increasing access, increasing access with measures to reduce disturbance). The results show a willingness of local populations to pay per year about €25 for the highest level of ecological restoration, while they were only willing to allocate about €5 for additional footpaths and hides.

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Over the past years, ω3 fatty acids, namely EPA and DHA, have been recognized as presenting multiple health benefits. Several studies consider fish oil as the most important source of EPA and DHA. Nowadays, canned fish industry plays a very important role in Portuguese economy. However, expansion of this business brought some environmental concerns due to the high amount of by-products generated. Nevertheless, this problem can be substantially reduced by the recovery of some of the by-product components, diminishing its contamination load and simultaneously obtaining value-added products. This study was born from the growing interest in obtaining new sources of lipids rich in ω3 fatty acids, combined with environmental concerns related to the production of wastes from the fish canning industries, rich in these compounds. It thus intends to evaluate lipid extraction methods in liquid by-products from the fish canning industry, aiming to obtain fractions rich in ω3 fatty acids. Additionally, in a biorefining concept, the protein content of the remaining aqueous fractions was also quantified.

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Small-scale spatial and temporal variability in animal abundance is an intrinsic characteristic of marine ecosystems but remains largely unknown for most animals, including coral reef fishes. In this study, we used a remote autonomous unbaited video system and recorded reef fish assemblages during daylight hours, 10 times a day for 34 consecutive days in a branching coral patch of the lagoon of New Caledonia. In total, 50 031 fish observations belonging to 114 taxa, 66 genera and 31 families were recorded in 256 recorded videos. Carnivores and herbivore-detritus feeders dominated the trophic structure. We found significant variations in the composition of fish assemblages between times of day. Taxa richness and fish abundance were greater in the early morning and in the late afternoon than during the day. Fourteen taxa displayed well-defined temporal patterns in abundance with one taxon influenced by time of day, six influenced by tidal state and seven influenced by both time of day and tidal state. None of these 14 taxa were piscivores, 10 were herbivore-detritus feeders, three were carnivores and one was plankton feeder. Our results suggest a diel migration from feeding grounds to shelter areas and highlight the importance of taking into account small-scale temporal variability in animal diversity and abundance when studying connectivity between habitats and monitoring communities.

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During the period from 2011 - 2015 with the aim of this study was to systematically review and in particular the revised classification of the Persian Gulf (and the Strait of Hormuz) and to obtain new information about the final confirmed list of fish species of Iranian waters of the Persian Gulf (and Hormuz Strait), samples of museums, surveys and sampling, and comparative study of all available sources and documentation was done. Classification systematic of sharks and batoids and bony fishes. Based on the results, the final list of approved fish of the Persian Gulf (including the Strait of Hormuz and Gulf of Oman border region) are 907 species in 157 families, of which 93 species of fish with 28 cartilaginous families (including 18 families with 60 species and 10 families with 34 species of shark and batoids); and 129 families with 814 species of bony fishes are. The presence of 11 new family with only one representative species in the area include Veliferidae, Zeidae, Sebastidae, Stomiidae, Dalatiidae, Zanclidae, Pempheridae, Lophiidae Kuhliidae, Etmoptridae and Chlorophthalmidae also recently introduced and approved. The two families based Creediidae Clinidae and their larvae samples for newly identified area. 62 families with mono-species and 25 families with more than 10 species are present including Gobiidae (53), Carangide (48), Labride (41), Blenniidae (34), Apogonidae (32) and Lutjanidae (31) of bony fishes, Carcharhinidae (26) of sharks and Dasyatidae (12) in terms of number of species of batoids most families to have their data partitioning. Also, 13 species as well as endemic species introduced the Persian Gulf and have been approved in terms of geographical expansion of the Persian Gulf are unique to the area.Two species of the family Poeciliidae and Cyprinodontidae have species of fresh water to the brackish coastal habitats have found a way;in addition to 11 types of families Carcharhinidae, Clupeidae, Chanidae, Gobidae, Mugilidae, Sparidae also as a species, with a focus on freshwater river basins in the south of the country have been found. In this study, it was found that out of 907 species have been reported from the study area, 294 species (32.4 %) to benthic habitats (Benthic habitats) and 613 species (67.6 %) in pelagic habitats (Pelagic habitats) belong. Coral reefs and rocky habitats in the range of benthic fish (129 species - 14.3 %) and reef associated fishes in the range of pelagic fishes (432 species – 47.8 %), the highest number and percentage of habitat diversity (Species habitats) have been allocated. As well as fish habitats with sea grass and algae beds in benthic habitat (17 species- 1.9 %) and pelagic - Oceanic (Open sea) in the whole pelagic fish (30 species – 3.3 %), the lowest number and percentage of habitat diversity into account. From the perspective of animal geography (Zoogeography) and habitat overlaps and similarities (Habitat overlapping) fish fauna of the Persian Gulf compared with other similar seas (tropical and subtropical, and warm temperate) in the Indian Ocean area - calm on the surface, based on the presence of certain species that the fish fauna of the Persian Gulf to the Red Sea and the Bay of Bengal (East Arabian Sea) compared to other regions in the Indian Ocean (Pacific) is closer (about 50%), and the Mediterranean (East area) and The Hawaiian Islands have the lowest overlap and similarity of habitat and species (about 10%).

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For decades, global climate change has directly and indirectly affected the structure and function of ecosystems. Abrupt changes in biodiversity have been observed in response to linear or sudden modifications to the environment. These abrupt shifts can cause long-term reorganizations within ecosystems, with communities exhibiting new functional responses to environmental factors. Over the last 3 decades, the Gironde estuary in southwest France has experienced 2 abrupt shifts in both the physical and chemical environments and the pelagic community. Rather than describing these shifts and their origins, we focused on the 3 inter-shift periods, describing the structure of the fish community and its relationship with the environment during these periods. We described fish biodiversity using a limited set of descriptors, taking into account both species composition and relative species abundances. Inter-shift ecosystem states were defined based on the relationship between this description and the hydro-physico-chemical variables and climatic indices defining the main features of the environment. This relationship was described using generalized linear mixed models on the entire time series and for each inter-shift period. Our results indicate that (1) the fish community structure has been significantly modified, (2) environmental drivers influencing fish diversity have changed during these 3 periods, and (3) the fish-environment relationships have been modified over time. From this, we conclude a regime shift has occurred in the Gironde estuary. We also highlight that anthropogenic influences have increased, which re-emphasizes the importance of local management in maintaining fish diversity and associated goods and services within the context of climate change.

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Les organismes aquatiques sont adaptés à une grande variabilité hydrique et thermique des rivières. Malgré ceci, la régulation des eaux suscite des changements aux débits qui peuvent provoquer des impacts négatifs sur la biodiversité et les processus écologiques en rivière. Celle-ci peut aussi causer des modifications au niveau des régimes thermiques et des caractéristiques de l’habitat du poisson. Des données environnementales et biologiques décrivant l’habitat du poisson existent, mais elles sont incomplètes pour plusieurs rivières au Canada et de faible qualité, limitant les relations quantitatives débit-température-poissons à un petit nombre de rivières ou à une région étudiée. La recherche menée dans le cadre de mon doctorat concerne les impacts de la génération d'hydroélectricité sur les rivières; soit les changements aux régimes hydriques et thermiques reliés à la régulation des eaux sur la variation des communautés ichtyologiques qui habitent les rivières régulées et naturelles au Canada. Suite à une comparaison d’échantillonnage de pêche, une méthode constante pour obtenir des bons estimés de poisson (richesse, densité et biomasse des espèces) a été établie pour évaluer la structure de la communauté de poissons pour l’ensemble des rivières ciblées par l’étude. Afin de mieux comprendre ces changements environnementaux, les principales composantes décrivant ces régimes ont été identifiées et l’altération des régimes hydriques pour certaines rivières régulées a été quantifiée. Ces résultats ont servi à établir la relation significative entre le degré de changement biotique et le degré de changement hydrique pour illustrer les différences entre les régimes de régulation. Pour faire un complément aux indices biotiques déjà calculés pour l’ensemble des communautés de poissons (diversité, densité et biomasse des espèces par rivière), les différences au niveau des guildes de poissons ont été quantifiées pour expliquer les divers effets écologiques dus aux changements de régimes hydriques et thermiques provenant de la gestion des barrages. Ces derniers résultats servent à prédire pour quels traits écologiques ou groupes d’espèces de poissons les composantes hydriques et thermiques sont importantes. De plus, ces derniers résultats ont servi à mettre en valeur les variables décrivant les régimes thermiques qui ne sont pas toujours inclues dans les études hydro-écologiques. L’ensemble des résultats de cette thèse ont des retombées importantes sur la gestion des rivières en évaluant, de façon cohérente, l’impact de la régulation des rivières sur les communautés de poissons et en développant des outils de prévision pour la restauration des écosystèmes riverains.

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Background: At the end of 80s, cloning technologies with the increase of the antibodies’ sensibility made easier the development of technologies based on Fluorescence in situ Hibridation (FISH). Nowadays, It’s widely used in the field of basic investigation as much as clinic diagnostic. Method: FISH is a technique that combines molecular biology with histochemistry way to detect specific nucleotide sequences so that chromosome’s section or even whole chromosome can be marked on metaphases cells (cell in division) and on attached cellular nucleus. This detection is realized using DNA fluorescence probes (marked with fluorophores), that can be different according to the structures manage to detect: large single-locus probes, small unique-sequence probes, chromosome- or region-specific “paints” or repetitive sequence probes and genomic DNA probes. Some of the applications of this technique is that can be so useful in the detection of numerical and structural chromosomal alterations such as polyploidies or genomic rearrangement, to mapping metaphases cells and even to detect bacteria or another type of microorganism. In addition, FISH allows us to monitoring diseases (antitumor therapies, quantification of genomic altered cells…) and the precise location of chromosomic broken spots on tumor searching for new genes involved in cancer and detect and map interested known genes. Conclusion: FISH has many advantages ahead of conventional cytogenetic techniques (bands G karyotype) overall at the time of establish a clinic diagnostic to detect tumors and chromosomic aberration, presenting a higher sensibility and specificity as well as being a relative quick technique (24 hours).

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In September 2013, staff from the University of the South Pacific (USP) Honiara campus, the Secretariat of the Pacific Community (SPC) and IFREMER (UR LEADNC, AMBIO project) in New Caledonia, and the French Institute for Pacific Coral Reefs (IRCP) in Moorea, French Polynesia, co-facilitated a workshop entitled “Different survey methods of coral reef fish, including the methods based on underwater video”. The workshop was attended by students from USP, NGO and fisheries officers. They were trained to several underwater visual census techniques and to the STAVIRO video-based technique, including both field work and data analysis.

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Seasonal pathologies reduce the profitability and sustainability of the shrimp-farming industry in New Caledonia. A study was therefore conducted to estimate the effects of polyculture of blue shrimp with goldline rabbitfish or mullet on production performance and environmental quality. The fish did not affect shrimp production, and the combined shrimp/fish yields were significantly greater than the yield from shrimp monoculture. Changes in environmental quality in all treatments were few and minor throughout the culture period.

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Tese de Doutoramento, Ciências do Mar, da Terra e do Ambiente, Ramo: Ciências do Mar, Especialização em Ecologia Marinha, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2016