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Differential expression of myogenic regulatory factor MyoD in pacu skeletal muscle (Piaractus mesopotamicus Holmberg 1887: Serrasalminae, Characidae, Teleostei) during juvenile and adult growth phases

Alves de Almeida, Fernanda Losi; Carvalho, Robson Francisco; Pinhal, Danillo; Padovani, Carlos Roberto; Martins, Cesar; Dal Pai-Silva, Maeli
Fonte: Pergamon-Elsevier B.V. Ltd Publicador: Pergamon-Elsevier B.V. Ltd
Tipo: Artigo de Revista Científica Formato: 1306-1311
ENG
Relevância na Pesquisa
46.6%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Processo FAPESP: 04/12756-3; Processo FAPESP: 05/56587-3; Skeletal muscle is the edible part of the fish. It grows by hypertrophy and hyperplasia, events regulated by differential expression of myogenic regulatory factors (MRFs). The study of muscle growth mechanisms in fish is very important in fish farming development. Pacu (Piaractus mesopotamicus) is one of the most important food species farmed in Brazil and has been extensively used in Brazilian aquaculture programs. The aim of this study was to analyze hyperplasia and hypertrophy and the MRF MyoD expression pattern in skeletal muscle of pacu (P. mesopotamicus) during juvenile and adult growth stages. Juvenile (n = 5) and adult (n = 5) fish were anaesthetized, sacrificed, and weight (g) and total length (cm) determined. White dorsal region muscle samples were collected and immersed in liquid nitrogen. Transverse sections (10 mu m thick) were stained with Haematoxilin-Eosin (HE) for morphological and morphometric analysis. Smallest fiber diameter from 100 muscle fibers per animal was calculated in each growth phase. These fibers were grouped into three classes (<20, 20-50, and >50 mu m) to evaluate hypertrophy and hyperplasia in white skeletal muscle. MyoD gene expression was determined by semi-quantitative RTPCR. PCR products were cloned and sequenced. juvenile and adult pacu skeletal muscle had similar morphology. The large number of <20 mu m diameter muscle fibers observed in juvenile fish confirms active hyperplasia. In adult fish...

Rearing temperature induces changes in muscle growth and gene expression in juvenile pacu (Piaractus mesopotamicus)

Paula, Tassiana Gutierrez de; Alves de Almeida, Fernanda Losi; Carani, Fernanda Regina; Vechetti-Junior, Ivan Jose; Padovani, Carlos Roberto; Simoes Salomao, Rondinelle Arthur; Mareco, Edson Assuncao; Santos, Vander Bruno dos; Dal-Pai-Silva, Maeli
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 31-37
ENG
Relevância na Pesquisa
46.6%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Processo FAPESP: 11/14538-7; Pacu (Piaractus mesopotamicus) is a fast-growing fish that is extensively used in Brazilian aquaculture programs and shows a wide range of thermal tolerance. Because temperature is an environmental factor that influences the growth rate of fish and is directly related to muscle plasticity and growth, we hypothesized that different rearing temperatures in juvenile pacu, which exhibits intense muscle growth by hyperplasia, can potentially alter the muscle growth patterns of this species. The aim of this study was to analyze the muscle growth characteristics together with the expression of the myogenic regulatory factors MyoD and myogenin and the growth factor myostatin in juvenile pacu that were submitted to different rearing temperatures. Juvenile fish (1.5 g weight) were distributed in tanks containing water and maintained at 24 degrees C (G24), 28 degrees C (G28) and 32 degrees C (G32) (three replicates for each group) for 60 days. At days 30 and 60, the fish were anesthetized and euthanized, and muscle samples (n = 12) were collected for morphological, morphometric and gene expression analyses. At day 30...

Among-sibling differences in the phenotypes of juvenile fish depend on their location within the egg mass and maternal dominance rank

Burton, Tim; Hoogenboom, M. O.; Beevers, N. D.; Armstrong, J. D.; Metcalfe, N. B.
Fonte: The Royal Society Publicador: The Royal Society
Tipo: Artigo de Revista Científica
Publicado em 22/01/2013 EN
Relevância na Pesquisa
46.37%
We investigated whether among-sibling differences in the phenotypes of juvenile fish were systematically related to the position in the egg mass where each individual developed during oogenesis. We sampled eggs from the front, middle and rear thirds of the egg mass in female brown trout of known dominance rank. In the resulting juveniles, we then measured traits that are related to individual fitness: body size, social status and standard metabolic rate (SMR). When controlling for differences among females in mean egg size, siblings from dominant mothers were initially larger (and had a lower mass-corrected SMR) if they developed from eggs at the rear of the egg mass. However, heterogeneity in the size of siblings from different positions in the egg mass diminished in lower-ranking females. Location of the egg within the egg mass also affected the social dominance of the resulting juvenile fish, although the direction of this effect varied with developmental age. This study provides the first evidence of a systematic basis for among-sibling differences in the phenotypes of offspring in a highly fecund organism.

Investigations on juvenile fish excluder cum shrimp sorting device (JFE-SSD)

Boopendranath, Menothuparambil Ravunny; Pravin, Puthra; Gibinkumar, Therodath Rajan; Sabu, Sarasan; Madhu, Vettiyattil Ramakrishnan
Fonte: Springer International Publishing Publicador: Springer International Publishing
Tipo: Artigo de Revista Científica
Publicado em 21/06/2013 EN
Relevância na Pesquisa
46.47%
Penaeid shrimp is a major resource in India contributing about 7.4% of the total marine fish landings. They are mostly landed by small mechanized trawlers. Shrimp trawling generates large quantities of bycatch mostly consisting of juvenile fishes, due to use of small mesh size in codends of trawl nets. Juvenile Fish Excluder cum Shrimp Sorting Device (JFE-SSD) is a bycatch reduction device with an in situ sorting mechanism, which replaces the conventional codend in a trawl. The device was designed to catch shrimps and commercially important fish species using a specially designed oval sorting grid with appropriate bar spacing and dual codends. Shrimp sorting efficiency and bycatch exclusion characteristics of JFE-SSD attached to a 29.6 m shrimp trawl, was tested by experimental fishing along the coastal waters off Cochin, India. Out of a total of 317.07 kg of catch encountered in the JFE-SSD installed trawl, 58.22% was retained in lower codend, 17.53% in upper codend and 24.25%, mostly consisting of juveniles and sub-adults of finfishes and shellfishes, was excluded from upper codend. The mean CPUE registered for upper and lower codend were 7.23±1.04 SE and 5.84±0.96 SE kg h-1 respectively. The CPUE of shrimps retained in upper and lower codends were significantly different (Kruskal-Wallis test (1...

Connectivity between juvenile and adult fish populations: do adults remain near their recruitment estuaries?

Gillanders, B.
Fonte: Inter-Research Publicador: Inter-Research
Tipo: Artigo de Revista Científica
Publicado em //2002 EN
Relevância na Pesquisa
46.66%
Juvenile snapper Pagrus auratus (Sparidae) were collected from 15 estuaries during the recruitment season of 1998–99 and their otoliths were analysed to determine concentrations of chemical elements. Differences in elemental composition of juveniles were found among estuaries or groups of estuaries suggesting that the nursery or recruitment estuary of adult fish could be determined by analysing the juvenile region of adult otoliths. Adult fish from the commercial fishery in the vicinity of Sydney, New South Wales, Australia were then collected, their ages estimated and fish with birth years during 1998–99 selected for microchemical analysis to determine their recruitment estuary. Maximum likelihood analyses were used to determine the proportion of juvenile fish and adult fish from different regions (Wallis Lake, Sydney estuaries, Eden, and other estuaries). For juvenile fish, the actual composition ranged from 7 to 53% depending on the estuary or group of estuaries and the estimate of proportion of juveniles from the different estuaries ranged from 7.24 to 48.21% suggesting an error rate of <1 to 4.79%. Most (89%) adult fish caught as part of the snapper fishery in the Sydney region originated from local estuaries, although about 9% of fish had Eden as their recruitment estuary and 2% had come from the remaining estuaries excluding Wallis Lake...

Marine nurseries and effective juvenile habitats: concepts and applications

Dahlgren, C.; Kellison, G.; Adams, A.; Gillanders, B.; Kendall, M.; Layman, C.; Ley, J.; Nagelkerken, I.; Serafy, J.
Fonte: Inter-research Publicador: Inter-research
Tipo: Artigo de Revista Científica
Publicado em //2006 EN
Relevância na Pesquisa
46.28%
Much recent attention has been focused on juvenile fish and invertebrate habitat use, particularly defining and identifying marine nurseries. The most significant advancement in this area has been the development of a standardized framework for assessing the relative importance of juvenile habitats and classifying the most productive as nurseries. Within this framework, a marine nursery is defined as a juvenile habitat for a particular species that contributes a greater than average number of individuals to the adult population on a per-unit-area basis, as compared to other habitats used by juveniles. While the nursery definition and framework provides a powerful approach to identifying habitats for conservation and restoration efforts, it can omit habitats that have a small per-unit-area contribution to adult populations, but may be essential for sustaining adult populations. Here we build on the nursery concept by developing a framework for evaluating juvenile habitats based on their overall contribution to adult populations, and introduce the concept of Effective Juvenile Habitat (EJH) to refer to habitats that make a greater than average overall contribution to adult populations.; Craig P. Dahlgren, G. Todd Kellison, Aaron J. Adams...

Spatial and temporal variation in fish community structure of a marine embayment in Zanzibar, Tanzania

Lugendo, B.; de Groene, A.; Cornelissen, I.; Pronker, A.; Nagelkerken, I.; van der Velde, G.; Mgaya, Y.
Fonte: Kluwer Academic Publ Publicador: Kluwer Academic Publ
Tipo: Artigo de Revista Científica
Publicado em //2007 EN
Relevância na Pesquisa
46.25%
Spatial and temporal variation in the fish community structure were studied in a tropical non-estuarine embayment in Chwaka Bay, Zanzibar (Tanzania). Fish samples were collected bi-monthly (at each spring low tide) for 1 year (November 2001–October 2002) from a range of bay habitats ranging from mangroves deep inside the bay to seagrass beds close to the mouth of the bay. Additionally, environmental variables were examined to determine their relationship with the fish community structure. Being a non-estuarine embayment, the environmental variables as well as the fish community structure in each habitat remained relatively constant for most part of the year; however, a marked decline was observed during the rainy period (April–May). Significant variations in fish community variables (density, biomass and species richness) and in water temperature and salinity were observed during the rainy season in all habitats, with larger changes in the mangrove and mud/sand flats habitats than in the seagrass beds. Seasonal variations in water clarity and dissolved oxygen were not significant, though. Many species disappeared from the mangrove and mud/sand flats habitats during the rainy season and those which persisted showed a remarkable decrease in density. Moreover...

Connectivity between estuarine and coastal fish populations: Contributions of estuaries are not consistent over time

Reis Dos Santos, P.; Tanner, S.; Vasconcelos, R.; Elsdon, T.; Cabral, H.; Gillanders, B.
Fonte: Inter-research Publicador: Inter-research
Tipo: Artigo de Revista Científica
Publicado em //2013 EN
Relevância na Pesquisa
46.42%
Otolith elemental signatures (Li:Ca, Mg:Ca, Mn:Ca, Cu:Ca, Sr:Ca, Ba:Ca and Pb:Ca) of Age-0 juveniles of flounder Platichthys flesus and sea bass Dicentrarchus labrax, collected from estuarine systems along the Portuguese coast in 2006 and 2009, were used as baseline signatures to identify the estuarine nursery of Age-3+ and 2+ coastal fish matching the juvenile year classes. Otolith elemental signatures were determined via Laser Ablation Inductively Coupled Plasma Mass Spectrometry, and successfully identified the estuarine origin of the majority of coastal fish to characterized baseline estuaries. Relative contributions of individual estuaries to coastal areas, quantified using maximum likelihood estimation, varied over time for the 2 year classes analysed. However, some general patterns were discernible in terms of important estuaries versus those with minor or negligible contributions. Assigned nursery origins varied among species and suggested large scale movements along the coast. For P. flesus the main source for recruits changed between year classes from Ria de Aveiro (69%) to the Douro estuary (59%). The Mondego estuary, located near the latitudinal limit of P. flesus, contributed moderate numbers to coastal populations. The Tejo estuary was the most important estuary for D. labrax in both years sampled (55 and 50%...

Dietary fish oil replacement with palm or poultry oil increases fillet oxidative stability and decreases liver glutathione peroxidase activity in barramundi (Lates calcarifer)

Wan Ahmad, W.A.; Stone, D.A.; Schuller, K.A.
Fonte: Springer Netherlands Publicador: Springer Netherlands
Tipo: Artigo de Revista Científica
Publicado em //2013 EN
Relevância na Pesquisa
46.25%
Complete dietary fish oil replacement with palm or poultry oil in barramundi (Lates calcarifer) had no detrimental effects on growth or hepatosomatic index of juvenile fish up to an average size of ~50 g. However, it significantly decreased the omega-3 (n-3) long-chain polyunsaturated fatty acid content of the fish muscle (fillet) lipids. This was particularly true for eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) which are recognised for their health beneficial effects in the human diet. As a result of their decreased EPA and DHA content, the peroxidation index of the muscle lipids was also decreased. This was associated with increased simulated retail storage shelf life as indicated by decreased thiobarbituric acid reactive substances in muscle samples from fish fed the palm or poultry oil-based diets. Concomitantly, glutathione peroxidase (GPx) activity, but not glutathione S-transferase (GST) activity or reduced glutathione concentration, was significantly reduced in the liver of barramundi fed the palm or poultry oil-based diets as compared with the fish fed the fish oil-based diet. Furthermore, GPx and GST activity were very low in muscle, much lower than in gastrointestinal tract, liver or swim bladder. Therefore...

Effects of exposures to the plasticiser, di-n-butyl phthalate and the pharmaceutical, flutamide on the biomarkers of reproduction in Australian freshwater fish species, Murray rainbowfish (Melanotaenia fluviatilis).

Bhatia, Harpreet
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2014
Relevância na Pesquisa
46.73%
With the detection of anti-androgenicity in the effluents from the wastewater treatment plants (WWTPs), there is speculation that sexual disruption in fish is a multi-causal condition involving anti-androgens. Much of the research has focussed on deciphering the modes-of-action (MoAs) of (anti)estrogens and androgens. However, effects of androgen receptor (AR) antagonists have not been fully characterised and remain elusive in fish. The present study aimed to investigate the effects of the classic mammalian anti-androgen, flutamide and the emerging industrial pollutant, di-n-butyl phthalate (DnBP) on the biomarkers of reproduction in adult (male and female) and juvenile Murray rainbowfish (Melanotaenia fluviatilis). Flutamide is the “pure” anti-androgen designed to treat prostate cancer in men and polycystic ovarian syndrome in women. It has also been extensively used in toxicity testing in mammals. The in vitro anti-androgenic activity in the aquatic environment worldwide is measured in flutamide equivalents. Phthalates are a class of synthetic industrial chemicals commonly found in the aquatic environment worldwide. They have been recognised as anti-androgens in male mammals but little is known about their endocrine-disrupting effects in the native Australian fish species. Due to its detection in freshwater both in Australia and worldwide and considering its higher solubility in water (11 mg/L)...

Habitat selection at settlement and post-settlement dynamics in juvenile fish communities in the New Caledonia lagoon

Mellin, Camille
Fonte: Societe Francaise d'ichtyologie Publicador: Societe Francaise d'ichtyologie
Tipo: Artigo de Revista Científica
Publicado em //2009 EN
Relevância na Pesquisa
56.62%
Habitat suitability influences the growth and survival of coral reef fish juveniles, and thus the success of their recruitment in adult populations. The ultimate aim of the PhD research was to assess the relationships between the habitat characteristics in the south-west lagoon of New Caledonia at different scales, growth and abundances of juvenile fish. A photographic method was first developed in order to quantify the characteristics of coral microhabitats for juvenile fish. This method was then used for studying the relationship between microhabitat characteristics, growth trajectories back-calculated from otolith analysis, and abundances of juvenile Pomacentrus moluccensis. No significant difference was showed between the growth trajectories of individuals collected from different coral colonies. However, the density-dependent mortality of juveniles increased when the volume of holes of coral colonies decreased. At the spatial scale of two islets of the lagoon, significant spatial differences were observed in back-calculated growth trajectories, size and/or age at settlement of juveniles of Chromis viridis, Lethrinus genivittatus and Siganus fuscescens. A novel statistical procedure revealed the growth-selective mortality of juveniles C. viridis...

Estuarine production of resident and nursery fish species: Conditioning by drought events?

Dolbeth, M.; Martinho, F.; Viegas, I.; Cabral, H.; Pardal, M. A.
Fonte: Universidade de Coimbra Publicador: Universidade de Coimbra
Tipo: Artigo de Revista Científica Formato: aplication/PDF
ENG
Relevância na Pesquisa
46.21%
The production of resident (Pomatoschistus minutus and Pomatoschistus microps) and marine juvenile fish species using the Mondego estuary (central Portugal) as nursery grounds (Dicentrarchus labrax, Platichthys flesus, Solea solea), was assessed in order to: (1) understand the potential of the estuary for fish production; (2) know the production of nursery fish species likely to be exported to the coastal stocks; and (3) how anthropogenic and natural stress could influence the estimated production. Sampling occurred from June 2003 to May 2006 and together the 5 species in study comprised around 70% of the whole fish community numbers and biomass. Increasing drought conditions were observed, starting with a normal hydrological year in 2003 until attaining a severe drought in 2005, which resulted in low river discharges (1/3 of the mean river discharges in 2003). Additionally, high water temperatures were observed in 2003 and 2005 (24 and 26 °C, night temperatures). The secondary production was estimated using the increment summation method, after recognition of the cohorts. Production was in general lower in the Mondego estuary when compared to other systems, which was associated to the estuary's small area (only 3.4 km2, less than 1/4 of area compared to other studied systems). Dicentrarchus labrax was among the most productive species. Production decreased in the drought year for all species...

Habitat Associations of Juvenile Fish at Ningaloo Reef, Western Australia: The Importance of Coral and Algae

Wilson, Shaun K.; Depczynski, Martial; Fisher, Rebecca; Holmes, Thomas H.; O'Leary, Rebecca A.; Tinkler, Paul
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 07/12/2010 EN
Relevância na Pesquisa
46.58%
Habitat specificity plays a pivotal role in forming community patterns in coral reef fishes, yet considerable uncertainty remains as to the extent of this selectivity, particularly among newly settled recruits. Here we quantified habitat specificity of juvenile coral reef fish at three ecological levels; algal meadows vs. coral reefs, live vs. dead coral and among different coral morphologies. In total, 6979 individuals from 11 families and 56 species were censused along Ningaloo Reef, Western Australia. Juvenile fishes exhibited divergence in habitat use and specialization among species and at all study scales. Despite the close proximity of coral reef and algal meadows (10's of metres) 25 species were unique to coral reef habitats, and seven to algal meadows. Of the seven unique to algal meadows, several species are known to occupy coral reef habitat as adults, suggesting possible ontogenetic shifts in habitat use. Selectivity between live and dead coral was found to be species-specific. In particular, juvenile scarids were found predominantly on the skeletons of dead coral whereas many damsel and butterfly fishes were closely associated with live coral habitat. Among the coral dependent species, coral morphology played a key role in juvenile distribution. Corymbose corals supported a disproportionate number of coral species and individuals relative to their availability...

Gills of juvenile fish piaractus mesopotamicus as histological biomarkers for experimental sub-lethal contamination with the Organophosphorus Azodrin®400

Rudnicki,Cácia Aparecida Mendes; Melo,Gisele Cristiane; Donatti,Lucélia; Kawall,Helena Gonçalves; Fanta,Edith
Fonte: Instituto de Tecnologia do Paraná - Tecpar Publicador: Instituto de Tecnologia do Paraná - Tecpar
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2009 EN
Relevância na Pesquisa
46.28%
Piaractus mesopotamicus is a freshwater native fish from rivers of the Paraná-Paraguay Basin and of the Pantanal region and has been used for repopulation programs in Brazil. Juvenile fishes were exposed to the sub-lethal dose of 1.08mg/L of the OP Azodrin®400 containing 0.43µL/L of the active principle monocrotophos for 96 h. A frequent pathology in the gills at all times of exposure was epithelial detachment, from minimal until 24 h of exposure, to intense after 48 h of contamination. Deformed pillar cells in the respiratory lamellae leading to irregular blood spaces and blood congestion, as well as hyperplasia and lamellar fusion were observed. These histopathologies suggested that 48 h after T0 was an important time when a reduction in the capability for gaseous exchange with consequent weakening of the fishes' condition could occur. This could impair growth and development of juveniles introduced in water bodies for repopulation programs.

Fish composition and prey utilization of the black skimmer (Rynchops niger) in mar Chiquita coastal lagoon, Argentina

Mariano-Jelicich,Rocío; García,Germán; Favero,Marco
Fonte: Universidade de São Paulo, Instituto Oceanográfico Publicador: Universidade de São Paulo, Instituto Oceanográfico
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2014 EN
Relevância na Pesquisa
46.24%
Lagoons along the western coast of the South Atlantic Ocean shelter high densities of juvenile fish and are key areas for several seabirds that rely on the resources offered by this kind of ecosystem. The objective of this study was to analyze fish composition and abundance in shallow-water areas of the estuarine region of Mar Chiquita Coastal Lagoon (Argentina) and the diet composition of the Black skimmer (Rynchops niger) during its non-breeding season as well as evaluating its inter-annual variations. Fish were sampled with a beach-seine net and the skimmers' diet was analyzed from their pellets. The estuarine-dependent marine fishes were the best represented bio-ecological category followed by freshwater fishes. Significant differences were observed in fish abundance and composition between and within years. Species richness was higher during the summer season and during the first year sampled. The occurrence of freshwater fishes as an important and diverse group of the Mar Chiquita estuarine area contrasted with previous reports. The diet of the Black skimmer included freshwater, estuarine and marine fish species. Skimmers forage in the shallow waters of the estuarine area of the Mar Chiquita Coastal lagoon though little similarity was observed between its diet and local fish abundance. These results emphasize the importance of performing these evaluations in order to improve the quality of studies and the interpretations of top predators foraging ecology.

Recruitment and post-settlement growth of juvenile Merluccius merluccius on the western Mediterranean shelf; Reclutamiento y crecimiento post-asentamiento de los juveniles Merluccius merluccius en la plataforma de mediterráneo occidental

Morales-Nin, Beatriz; Moranta, Joan
Fonte: Consejo Superior de Investigaciones Científicas (España) Publicador: Consejo Superior de Investigaciones Científicas (España)
Tipo: Artículo
ENG
Relevância na Pesquisa
56.35%
Young-of-the-year European hake (Merluccius merluccius) were sampled during four seasonal cruises between November 1998 and September 1999. The greatest numbers and biomass were found in spring 1999. Some 73% of juvenile fish in terms of number, and 81% in terms of biomass, were caught at depths between 60 and 160 m on the outer western Mediterranean shelf, where the water temperature ranged between 13.5 and 14°C. The length composition of samples showed there to be small hake all year around, with modes between 7 and 11 cm total length depending on the season. Otolith analysis was used to establish age at settlement (62.7 days) and to determine seasonal growth. The monthly growth rates ranged from 1.2 cm month-1 for juvenile hake captured on February 1999 to 2.5 cm month-1 for ones captured in June. The growth rates are related to survival, as was shown by the calculated hatch dates and relative abundances of recruits. This work provides information on the first year of life, recruitment and growth processes in an important species of the Mediterranean demersal ecosystem which is heavily exploited by a recruitment fishery.; Juveniles de la merluza europea fueron muestreados durante cuatro cruceros estacionales realizados entre 1998 y 1999...

Fish communities associated with FADs

Deudero Company, María de la Salud; Morales-Nin, Beatriz; Merella, P.; Massutí, Enric; Alemany, Francesc
Fonte: CSIC - Instituto de Ciencias del Mar (ICM) Publicador: CSIC - Instituto de Ciencias del Mar (ICM)
Tipo: Artículo Formato: 442824 bytes; application/pdf
ENG
Relevância na Pesquisa
46.22%
Publicación online disponible en: http://www.icm.csic.es/scimar/index.php; Two groups of six fish aggregating devices (FADs) were deployed at two locations off the eastern coast of Majorca (Western Mediterranean). Samples were obtained fortnightly throughout a two-year period by means of hauls performed with an experimental purse seine. Two control areas were established to check the aggregation efficiency of the FADs. A total of 16 families and 26 species of fishes were recorded beneath FADs. Pelagic fishes, largely Trachurus picturatus, T. mediterraneus, T. trachurus, Naucrates ductor, Seriola dumerili and Coryphaena hippurus, dominated the fauna. The total fish abundance, number of species and length range of the species confirmed that the FAD community was significantly related to season (recruitment period), resulting in a sequential fish colonisation of the FADs during the study period. Some of the species were present only during a particular period, such as Trachurus spp. in spring and summer. Other species, although evident for a longer period, were more occasional in catches (Schedophilus ovalis, Balistes carolinensis and Polyprion americanus), and some others were also present in small quantities. Diversity and equitability of the fish community associated with FADs were higher in summer than in winter. Many species were more abundant around FADs than in open water controls. The species that showed the most distinct recruitment phase beneath the FADs were N. ductor...

Juvenile fish use of the shallow zone of beaches of the Cananéia-Iguape coastal system, southeastern Brazil

Favero, Jana Menegassi del; Dias, June Ferraz
Fonte: Universidade de São Paulo. Instituto Oceanográfico Publicador: Universidade de São Paulo. Instituto Oceanográfico
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; Formato: application/pdf
Publicado em 01/06/2015 ENG
Relevância na Pesquisa
46.42%
Abstract The purpose of the present study is to describe the juvenile fish use of the shallow zone of beaches of the Cananéia-Iguape coastal system, São Paulo, Brazil, analyzing its occurrence period and the patterns of utilization for the most abundant species. Using a beach seine monthly for one year, we sampled 13861 individuals, of 57 species and 24 families. The fish species used the study area for different proposes: Atherinella brasiliensis was sampled in all phases of gonadal development and considered as resident, juveniles of Trachinotus goodei used the beaches for growth and juveniles of Mugil curema and Mugil liza used the beaches as a route from the ocean to the estuary. Our results showed the importance of the sandy beaches for juvenile fish, especially in spring and summer when most juveniles occur and recruit. Unfortunately, this is the period of the most intense tourist activity. As many of the species studied are commercially important, this study highlighted the necessity of coastal habitat preservation for better fishery management.; Resumo O objetivo do presente estudo é descrever o uso por peixes juvenis da zona rasa de praias arenosas do sistema costeiro Cananéia-Iguape, São Paulo, Brasil, analisando o período de ocorrência e o padrão de utilização das espécies mais abundantes na área. Utilizando uma rede de arrasto de praia (picaré) mensalmente ao longo de um ano...

Endocrine and Neurobehavioral Effects from Flame Retardant Exposure in Early and Juvenile Life Stages of Zebrafish

Macaulay, Laura Jean
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Dissertação
Publicado em //2015
Relevância na Pesquisa
46.7%

Polybrominated diphenyl ethers (PBDEs) are a class of flame retardant chemicals that were added to furniture foam, electronics, plastics, and some textiles to reduce their flammability. While PBDEs have been phased out from use in current products, huge reservoirs of products containing PBDEs still exist. It is likely exposure to PBDEs will continue as older products are discarded and recycled. PBDEs are ubiquitous contaminants in indoor and outdoor environments due to their widespread use in many products and their ability to migrate out of treated materials.

Major health effect concerns from PBDE exposure identified in laboratory studies include neurotoxicity, reproductive/developmental toxicity, and thyroid disruption. Importantly, mammals metabolize PBDEs into the hydroxylated polybrominated diphenyl ethers (OH-BDEs), which are structurally similar to endogenous thyroid hormones. Thyroid hormones are essential for metabolic processes, growth, and development, particularly brain development. Multiple studies have demonstrated enhanced potency of OH-BDEs relative to the parent PBDE chemicals, particularly for neurodevelopmental processes. Additionally, in fish species, thyroid hormones are essential for transitioning between larval...

Distribution of fish in seagrass, mangroves and coral reefs: life-stage dependent habitat use in Honduras

Jaxion-Harm,Jessica; Saunders,James; Speight,Martin R
Fonte: Revista de Biología Tropical Publicador: Revista de Biología Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2012 EN
Relevância na Pesquisa
46.46%
Many coral reef fish exhibit habitat partitioning throughout their lifetimes. Such patterns are evident in the Caribbean where research has been predominantly conducted in the Eastern region. This work addressed the paucity of data regarding Honduran reef fish distribution in three habitat types (seagrass, mangroves, and coral reefs), by surveying fish on the islands of Utila and Cayos Cochinos off the coast of Honduras (part of the Mesoamerican barrier reef). During July 2nd - Aug 27th 2007 and June 22nd - Aug 17th, 2008, visual surveys (SCUBA and snorkel) were performed in belt transects in different areas: eleven coral reef, six seagrass beds, and six mangroves sites. Juvenile densities and total habitat surface area were used to calculate nursery value of seagrass and mangroves. A total of 113 fish species from 32 families were found during underwater surveys. Multi-dimensional analyses revealed distinct clusters of fish communities in each habitat type by separating fish associated with seagrass beds, mangroves, and coral reefs. Coral reefs showed the highest mean fish species richness and were dominated by adult fish, while juvenile fish characterized seagrass beds and mangrove sites. Habitat use differed widely at the fish species level. Scarus iseri (Striped Parrotfish)...