389 resultados para Sparus auratus


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In this research, 9 species of local and introduced fishes of the Zayandehroud River in Esfahan province (in the Sarmatian region belonging to the large paleoarctic fauna) in 6 seasons (winter 2003, spring, summer, autumn and winter 2004 and summer 2005) were parasitologically studied. The local fishes included alburnoides bipunctatus, Alburnus maculatus, Aphanius vladykovi, Capoeta aculeata & Capoeta damascina & the introduced fishes included Aristichthys nobilis, Carassius auratus, Ctenopharyngodon idella and Cyprinus carpio. Upon being hunted, the fishes were transferred alive to Esfahan Aquatics Breeding Center and physiologically studied after the determination of their species and genus by identification keys Berg (30), Coad (31), Saadati (51), Abdoli (20) and Holchic (38). 32 species of parasites were totally identified as follows: 6 Protozoan species including Ichthyophthirius multifiliis, 5 Trichodina species, 2 Myxobolus species including Myxobolus cristatus & Myxobolus saidovi, 16 monogenea species including Dactylogyrus alatus. D. anchorutus, D. baueri, D. chalcalburni, D. chramuli, D. extensus, D. gracilis, D. lamellatus, D. lenkorani and D. pukher, 4 Dactylogyrus spp. 2 Gyrodactylus species, 1 species of Digenea, Diplostomum spthaceum, 4 species of Cestoda including Bothriocephallus gowkongensis, khawia armeniaca, Ligulaintestinalis. Caryophyllaeus sp. 1 Acanthocephala: Acanthocephalo rhynchoides cholodkowsky, 2 species of the crustaceans including the mature & copepodian stages of Lernaea cyprinacea & 1 sp of the genus Lamproglena. Out of all the 166 pcs of the fishes hunted in this research, 127 fishes (76.5%) were infected, and 39 fishes (23.50%) were not infected. In the fishes studied, having 14 of 32 species of the parasites identified, Capoeta aculeata displayed the most variety of infection, and having only 1 sp of the parasites. Aristichthys nobilis displayed the least variety of infection. The new findings of the research will follow: Myxobolus saidovi sp is reported for the 1st time from Iran's fresh water fishes, Alburnus maculatus and Capoeta aculeata are new hosts for M. saidovi and M. cristatus, respectively. Regarding monogenea Capoeta damascina & C. aculeata were reported as the new hosts for parasite D. pukher. The presence of D. pukher the infection of Capoeta aculeata with D. chramuli, D. lenkorani and D. gracilis in the Zayandehroud river were the 1st report. Regarding the Cestodea, Bothriocephalus gowkongensis was reported to be hosted by Aphanius Vladykovi for the 1St time in Iran.

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Animal-associated microbiotas form complex communities, which are suspected to play crucial functions for their host fitness. However, the biodiversity of these communities, including their differences between host species and individuals, has been scarcely studied, especially in case of skin-associated communities. In addition, the intraindividual variability (i.e. between body parts) has never been assessed to date. The objective of this study was to characterize skin bacterial communities of two teleostean fish species, namely the European seabass (Dicentrarchus labrax) and gilthead seabream (Sparus aurata), using a high-throughput DNA sequencing method. In order to focus on intrinsic factors of host-associated bacterial community variability, individuals of the two species were raised in controlled conditions. Bacterial diversity was assessed using a set of four complementary indices, describing the taxonomic and phylogenetic facets of biodiversity and their respective composition (based on presence/absence data) and structure (based on species relative abundances) components. Variability of bacterial diversity was quantified at the interspecific, interindividual and intraindividual scales. We demonstrated that fish surfaces host highly diverse bacterial communities, whose composition was very different from that of surrounding bacterioplankton. This high total biodiversity of skin-associated communities was supported by the important variability, between host species, individuals and the different body parts (dorsal, anal, pectoral and caudal fins).

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Seven native and introduced species of fish in south east Caspian Sea coast examined for parasite infestation during 2004-2006. Native fishes include Barbus capito, Carassius auratus, Cyprinus carpio, Rutilus frisii kutum, Rutilus rutilus, Stizostidion lucioperca, Alosa caspia persica, 24 ecto and endo parasites were found in different organs of 7 species of fishes of them 2 of the metazoan 12 species of crustacean Lernaea cyprinacea , Lamproglena pukhella nematodea and cestodea parasite were found and identified to species and genus including: Asymphylodora kubanicums, Caryophylaeus fimbericep, Rhabdochona hellichii, Contracecum sp. (larvae), Pronoprymna, Aspidogaster limacoides, Raphidascaris acus, Caryophylaeus laticeps, Rhabdochona hellichi, Clinostomum complanatum, Hysterothylacium sp., Rhipidocotyle illense of the metzoan 9 monogen species were found and identified to species and genus level including Dactylogyrus frisii, Dactylogyrus nybelini, Dactylogyrus extensus, Gyrodactylus sp, Dactylogyrus baueri, D. formosus, Gyrodactylus sprostonae, Gyrodactylus sp, Mazaocraes alosae. One psecies of digenea parasites belonging to Diplostomatidea family comprised Diplostomum Spathaceum. In comprise infestation parasite of fish species Cyprinus carpio, Rutilus frisii kutum with 25 precent and Stizostidion lucioperca with 5 percent showed the highest and lowest in infection between fishes in comprise ecological region rivers with 45 percent and Estuary 16 percent showed the highest and lowest percent of parasite Infection.

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Ornamental fish are more expensive in comparison with the other fish. It especially highlights in non-breeding fish (in imported one for importation costs). But of course, with entering the new and unhealthy fishes to aquarium or ponds, they may transmit a pathogen to others (interfere with Iran ornamental fish parasitic fauna). In this study (Dec. 2008- Sep. 2009), 400 fish gill arch from 4 species of ornamental fish (within focus on imported fish); namely, i.e. Goldfish (Carassius auratus), platyfish (Xiphophorus maculatus), Dwarf gourami (Colisa lalia) and Catfish (Hypostomus plecostomus) were inspected for gill ectoparasites and then pathologic effects (but in high- affected gill). In this study, seven protozoan and ten metazoan species, indeed seventeen parasite species were identified. Protozan parasites consist of: Trichodina spp. and Ichthyophthirius multifiliis were found in four fish species; Ichthyobodo necatrix (Costia necator/C. necatrix) and Cryptobia branchialis, were respectively found in Dwarf gourami and goldfish. The highest prevalence belongs to Ichthyophthirius (47%) in platyfish. Metazoan parasites consist of: Ancyrocephalus sp. (Dwarf gourami), Ancylodiscoides spp. (catfish and platyfish), Dactylogyrus vastator, D. baueri, D. formosus (only in goldfish) and Gyrodactylus spp. (in four fish species). The highest prevalence was related to Dactylogyrus vastator(82%) in goldfish. Histological effects in case with high prevalence of parasite were also observed, e.g., hypertrophy, Lamellar hyperplasia and fusion. In high-parasitized gill, there is dysfunction of gill.

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Em peixes, o cobre (Cu) é absorvido a partir da água, via branquial, e pela ingestão de água e alimento, via gastrintestinal. Para evitar reações não específicas prejudiciais e suprir proteínas dependentes de Cu, existem transportadores específicos, como as proteínas de absorção de alta afinidade ao Cu (CTR1) e as Cu-ATPases (ATP7), que auxiliam na translocação intracelular do metal. No presente estudo, os genes CTR1 e ATP7B foram identificados em Poecilia vivipara e os seus transcritos foram quantificados por RT-qPCR nas brânquias, no fígado e no intestino de guarús expostos (96 h) ao Cu (0, 5, 9 e 20 µg/L) em água doce e salgada (salinidade 24). Foram identificadas novas sequências nucleotídicas dos genes CTR1 (1560 pb, completa) e ATP7B (617 pb, parcial), as quais tiveram altos valores de identidade com as descritas para Fundulus heteroclitus (CTR1=81%) e Sparus aurata (ATP7B=81%). A análise por RT-qPCR indicou níveis de transcrição para CTR1 e ATP7B em todos os tecidos analisados. Em guarús na água doce, a maior expressão da CTR1 e da ATP7B se deu no fígado. Em guarús na água salgada, a maior expressão da CTR1 ocorreu no intestino, enquanto a da ATP7B se deu no fígado e intestino. Na água doce, a exposição ao Cu aumentou o conteúdo branquial e hepático de Cu, diminuiu os transcritos de CTR1 e ATP7B nas brânquias e aumentou os transcritos destes genes no fígado, sem alterar o conteúdo corporal de Cu. Na água salgada, a exposição ao Cu aumentou o conteúdo de Cu e diminuiu o transcrito de ATP7B no intestino, sem alterar o conteúdo corporal de Cu nos P. vivipara. Estes resultados indicam que a homeostasia do Cu em P. vivipara envolve a redução da expressão do CTR1 e ATP7B nas brânquias (água doce) e intestino (água salgada) para limitar a absorção do Cu e o aumento da expressão destes genes no fígado (água doce) para facilitar o armazenamento e desintoxicação do Cu.

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Early life stages of many marine organisms are being challenged by climate change, but little is known about their capacity to tolerate future ocean conditions. Here we investigated a comprehensive set of biological responses of larvae of two commercially important teleost fishes, Sparus aurata (gilthead seabream) and Argyrosomus regius (meagre), after exposure to future predictions of ocean warming (+4 °C) and acidification (ΔpH= 0.5). The combined effect of warming and hypercapnia elicited a decrease in the hatching success (by 26.4 and 14.3 % for S. aurata and A. regius, respectively) and larval survival (by half) in both species. The length for newly-hatched larvae was not significantly affected, but a significant effect of hypercapnia was found on larval growth. However, while S. aurata growth was reduced (24.8–36.4 % lower), A. regius growth slightly increased (3.2–12.9 % higher) under such condition. Under acidification, larvae of both species spent less time swimming, and displayed reduced attack and capture rates of prey. The impact of warming on these behavioural traits was opposite but less evident. While not studied in A. regius, the incidence of body malformations in S. aurata larvae increased significantly (more than tripled) under warmer and hypercapnic conditions. These morphological impairments and behavioural changes are expected to affect larval performance and recruitment success, and further influence the abundance of fish stocks and the population structure of these commercially important fish species. However, given the pace of ocean climate change, it is important not to forget that species may have the opportunity to acclimate and adapt.

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Dissertação de mest. em Biotecnologia, Faculdade de Engenharia de Recursos Naturais, Univ. do Algarve, 2004

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Dissertação de mest. em Aquacultura, Unidade de Ciências e Tecnologias dos Recursos Aquáticos, Univ. do Algarve, 1997

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Dissertação de mest. em Aquacultura, Unidade de Ciências e Tecnologias dos Recursos Aquáticos, Univ. do Algarve, 1997

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Dissertação de Mestrado, Biologia Marinha, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2016

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A two part experiment was conducted to assess the response of barramundi (Lates calcarifer; initial weight = 10.3 ± 0.03 g; mean ± S.D.) fed one of five diets with varying eicosapentaenoic acid (diets 1, 5, 10, 15 and 20 g/kg) or one of four diets with varying arachidonic acid (1, 6, 12, 18 g/kg) against a fish oil control diet. After 6 weeks of feeding, the addition of EPA or ARA did not impact on growth performance or feed utilisation. Analysis of the whole body fatty acids showed that these reflected those of the diets. The ARA retention demonstrated an inversely related curvilinear response to either EPA or ARA. The calculated marginal utilisation efficiencies of EPA and ARA were high (62.1 and 91.9 % respectively) and a dietary ARA requirement was defined (0.012 g/kg(0.796)/day). The partial cDNA sequences of genes regulating eicosanoid biosynthesis were identified in barramundi tissues, namely cyclooxygenase 1 (Lc COX1a, Lc COX1b), cyclooxygenase 2 (Lc COX2) and lipoxygenase (Lc ALOX-5). Both Lc COX2 and Lc ALOX-5 expression in the liver tissue were elevated in response to increasing dietary ARA, meanwhile expression levels of Lc COX2 and the mitochondrial fatty acid oxidation gene carnitine palmitoyltransferase 1 (Lc CPT1a) were elevated in the kidney. A low level of EPA increased the expression of Lc COX1b in the liver. Consideration should be given to the EPA to ARA balance for juvenile barramundi in light of nutritionally inducible nature of the cyclooxygenase and lipoxygenase enzymes.

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A minhoca (Eisenia fetida Savigny, 1826) é uma boa fonte de proteína. O elevado teor em humidade (82,80% ±2,128) e cinzas (10,70% ±2,345), principalmente terra, poderão ser um fator limitante à sua utilização como alimento para peixes. Com o objetivo de avaliar o interesse da utilização de E. fetida na alimentação de peixes, em 23 setembro 2014 foram capturados 22 juvenis de achigã (Micropterus salmoides Lacépède, 1802) (0+ anos) numa pequena barragem de rega Os achigãs foram colocados em três aquários para habituação a um alimentos compostos comercial. Três semanas depois 86,4% já ingeriam o alimento. A taxa de sobrevivência foi de 100%. Em 13 outubro 2014 foram escolhidos aleatoriamente 16 achigãs e colocados em dois aquários (8 peixes/aquário; 0,048 m3 de água). Os valores médios iniciais de peso, comprimento, fator K e densidade foram semelhantes nosdois aquários. No aquário G1 (minhocas) e aquário G2 (alimento composto) o peso, o comprimento, o fator K e a densidade iniciais foram, respetivamente, 13,62 g (±3,171) e 13,40 g (±3,002) (P>0,05); 10,49 cm (±0,757) e 10,39 cm (±0,649) (P>0,05); 1,160 (±0,043) e 1,179 (±0,082) (P>0,05); 2,27 kg/m3 e 2,23 kg/m3. No nosso estudo laboratorial a temperatura média da água variou entre 19,9ºC e 16,8ºC. Como em Portugal não se produzem alimentos específicos para achigãs foi utilizado um alimento composto comercial formulado para douradas (Sparus aurata L., 1758) e robalos (Dicentrarchus labrax L., 1758) (proteína 49,74%MS; gordura 18,07%MS; cinzas 11,57%MS; fibra bruta 0,84%MS; humidade 6,55%). No dia 88 do estudo (09 janeiro 2015) os valores médios de peso, comprimento, fator K e densidade nos aquários G1 e G2 foram, respetivamente, 17,57 g (±4,071) e 19,19 g (±4.811) (P<0,05); 10,88 cm (±0,875) e 11,29 cm (±0,871) (P<0,05); 1,346 (±0,051) e 1,311 (±0,061) (P>0,05); 2,93 kg/m3 e 3,20 kg/m3). Os resultados obtidos até agora parecem indicar que a E. fetida pode ser utilizada na alimentação de achigãs.

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Fisheries bycatches and discards constitute a significant problem in many fisheries worldwide. Unlike the pelagic purse-seine, the demersal purse seine usually targets high commercial value demersal species such as sea breams ( e. g., Diplodus spp., Pagellus spp., Sparus aurata) and the European sea bass ( Dicentrarchus labrax), while discards consist mainly of pelagic species and juveniles of the above mentioned species. In order to evaluate the efficiency of a selectivity device in reducing bycatch and consequently of discards in a demersal purse seine fishery, experimental deployments were carried out. The bycatch reducing device (BRD) consisted in the use of a panel of diamond-shaped mesh netting of 70 mm stretched mesh in the posterior part of the purse seine. Data from 61 experimental fishing trials allowed the evaluation of discards, with Scomber japonicus, Boops boops, Sardina pilchardus, Diplodus bellottii and Belone belone being the main discarded species. The mean discard ratio per set was 0.49 (+/- 0.30 standard deviation). The causes for discarding were also identified, with low commercial value being the most important reason. The results of the trials with BRD, were promising, with an average of 49% (+/- 24%) of the fish escaping per set, especially from those species that are most discarded. Overall, the use of this method for reducing discards can be considered positive for the following reasons: there is no need for structural modification of the fishing gear, the BRD is easy to deploy, and it is efficient in terms of species, sizes and quantities of fish that manage to escape. It therefore has significant benefits for the demersal purse seine fishery and possibly for other "metiers" as well.

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Gastric evacuation rates of the gilthead sea bream, Sparus aurata, fed with commercial pelleted food and polychaetes (Nereis diversicolor) were determined under experimental conditions. The estimated gastric evacuation rate for pelleted food was 7.97% h(-1), with a total time of digestion of approximately 9 h. The respective values for the natural food were 6.24% h(-1), with a total digestion time of approximately 12 h. The daily consumption of fish reared in earth ponds in a semi-intensive aquaculture facility was estimated through 24h cycles performed between April and August. The daily consumption varied from 18.58 to 31.98 mg g(-1). There was a constant increase in the average daily consumption per individual of 1.8-4.6 g (dry weight). During these cycles, samples of stomachs were taken and the contents preserved for further observation. The feeding behaviour of the reared fish was compared with a fish sample caught in the Ria Formosa lagoon. No common species were found between samples. A total of 38 prey were identified, which suggests that the gilthead sea bream is a non-specific predator. Despite the high abundance of natural prey in the ponds, the dependence of sea bream on pelleted food was high.