Search results for "aquaculture."
showing 10 items of 344 documents
The use of phage FCL-2 as an alternative to chemotherapy against columnaris disease in aquaculture
2015
Flavobacterium columnare, the causative agent of columnaris disease in fish, causes millions of dollars of losses in the US channel catfish industry alone, not to mention aquaculture industry worldwide. Novel methods are needed for the control and treatment of bacterial diseases in aquaculture to replace traditionally used chemotherapies. A potential solution could be the use of phages, i.e., bacterial viruses, host-specific and self-enriching particles that can be can easily distributed via water flow. We examined the efficacy of phages to combat columnaris disease. A previously isolated phage, FCL-2, infecting F. columnare, was characterized by sequencing. The 47 142 bp genome of the phag…
Ingestion of plastic and non-plastic microfibers by farmed gilthead sea bream (Sparus aurata) and common carp (Cyprinus carpio) at different life sta…
2021
Environmental pollution by plastic particles is of major global concern, as a potential threat to aquatic organisms and ecosystems. The accumulation of microplastics in freshwater and marine environments has strong ecological implications due to their long persistence, potential toxicity, and ability to adsorb other pollutants, acting as vectors of pathogens. Nevertheless, while the number of studies on the presence of microplastics in the wild fish increased, less attention has been paid to the farmed fish species. Here, we investigated the occurrence of microparticles in the digestive tracts of Sparus aurata and Cyprinus carpio at different life stages and reared by an intensive and semi-…
Nutritional Profiling and the Value of Processing By-Products from Gilthead Sea Bream (
2019
Fish processing industries generate a large volume of discards. In order to fulfil with the principles of a sustainable circular economy, it is necessary to maintain aquaculture by-products in the food chain through the production of high-value biomolecules that can be used as novel ingredients. In this study, we try to give value to the gilthead sea bream by-products, evaluating the composition and the nutritional value of the muscle and six discards commonly obtained from the fish processing industry (fishbone, gills, guts, heads, liver, and skin), which represent ≈ 61% of the whole fish. Significant differences were detected among muscle and by-products for fatty acid and amino acid prof…
ECONOMIC EVALUATION OF AQUACULTURE INVESTMENTS UNDER CONDITIONS OF RISK AND UNCERTAINTY IN THE MEDITERRANEAN SEA
2014
This study aims to analyze, from a technical and ec onomic point of view, the choice between alternative investments in aquaculture under condit ions of risk and uncertainty. In particular, a comparative analysis has been conducted between an inshore and an offshore farm producing European sea bass in the Mediterranean Sea. The app lied model refers to the theory of subjective probability, assigning a different probability to e xpected incomes during the investment period. Resul ts show an economic convenience of inshore with respect to offshore farming.
Risk assessment for parasites in cultures of Diplodus puntazzo (Sparidae) in the Western Mediterranean: Prospects of cross infection with Sparus aura…
2014
The sharpsnout seabream Diplodus puntazzo is of interest in Mediterranean fish farming. Disease is an important problem because parasites can spread quickly in culture conditions and fish often develop high parasite burdens. Here we assess the risk that documented parasites pose to the sustainability of D. puntazzo farming. This study specifically considers metazoan and protist parasites recorded from wild and farmed D. puntazzo in scientific literature. Risk assessment studies involve the identification, characterization and qualitative quantification of the risk in question (parasitoses in this case) and the probability of establishment. We considered the parasite species which may be dif…
Host–parasite relationship of Ceratomyxa puntazzi n. sp. (Myxozoa: Myxosporea) and sharpsnout seabream Diplodus puntazzo (Walbaum, 1792) from the Med…
2011
Sparidae are economically important fishes to both, fisheries and aquaculture in the Mediterranean. Species diversification is an important strategy for the development of Mediterranean aquaculture. One of the species recently introduced is the sharpsnout seabream Diplodus puntazzo (Walbaum, 1792). During a parasitological study of fish from the Gulf of Valencia and the Mar Menor (Spain), myxozoan spores belonging to the genus Ceratomyxa were found in the gall bladder of D. puntazzo. A morphological description of the spores, which includes histology and transmission electron microscopy (TEM) as well as molecular (SSU ribosomal DNA) data resulted in the erection of a new species, Ceratomyxa…
Gastric evacuation rate of burbot fed single-fish meals at different temperatures
1997
The gastric evacuation rates of burbot Lota lota, fed a single meal of vendace, Coregonus albula, were measured in the laboratory at five temperatures (1·3, 2·6, 4·8, 9·4 and 12·6° C). Gastric evacuation rate increased exponentially with increasing temperatrure, but the results suggest that gastric evacuation rates of burbot at low temperatures are lower than those of other freshwater fish species. Temperature and the ratio of meal weight to burbot weight were the most important factors affecting gastric evacuation rate. There was no significant difference in gastric evacuation rate between three different prey species: vendace, perch Perca fluviatilis, and smelt Osmerus eperlanus.
Occurrence and pathogenicity of Yersinia ruckeri at fish farms in northern and central Finland
1992
. Salmonid fish at fish farms in northern and central Finland and perch, Perca fluviatilis L., roach, Rutilus rutilus (L.), and whitefish, Coregonus sp., from four lakes in central Finland were studied between 1985 and 1990 for the occurrence of Yersinia ruckeri. The bacteria were found in fish from both areas, but in most cases, only single diseased salmon, Salmo salar L., brown trout, S. trutta L., rainbow trout, Oncorhynchus mykiss (Walbaum), whitefish and perch were encountered and were always connected with stress conditions. One clinical outbreak occured in salmon fingerlings in northern Finland, and the fish were successfully treated with trimethoprim-sulpha. Monthly monitoring of la…
Effects of sesame seed meal and bambaranut meal on growth, feed utilization and body composition of juvenile African catfish Clarias gariepinus
2014
Plant proteins are plausible fishmeal substitutes but are deficient in some essential amino acids (EAA) like lysine and methionine. Combination of different plant proteins with complimentary EAA could be a useful alternative. Bambaranut (Voandzeia subterranea) contains high amount of lysine while methionine is in sesame seed (Sesamum indicum). This experiment tested effects of combining sesame seed meal (SSM) and bambaranut meal (BNM) on juvenile African catfish Clarias gariepinus. Inclusion levels (%) of SSM:BNM in four novel diets were feed 1 (F1) 0:35, feed 2 (F2) 11.7:23.3, feed 3 (F3) 23.3:11.7, feed 4 (F4) 35:0. Catfish (initial weight ± SD 11.7 ± 0.56 g) were stocked in four replicat…
Screening of microalgae and LED grow light spectra for effective removal of dissolved nutrients from cold-water recirculating aquaculture system (RAS…
2019
Popularity of recirculating aquaculture systems (RAS) is increasing. Because of the high water recirculation rate, dissolved nutrients originating from fish feed are concentrated enough in RAS wastewater (WW) to enable growth of primary producers, e.g. microalgae. This study evaluated nitrate-nitrogen (NO3-N) and phosphate-phosphorus (PO4-P) removal efficiency of ten temperate zone freshwater microalgae species during their exponential growth phase in unfiltered RAS WW at 17 ± 0.5 °C. Growth and nutrient uptake efficiency of six green and four non-green microalgae strains were compared between WW and reference growth medium in batch monocultures. The effect of three different LED grow light…