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Liver damages and nuclear abnormalities in erythrocytes of Atherinella brasiliensis (Actynopterigii, Atherinopsidade) from two beaches in Southeast of Brazil
Fernandez, Welingtom S.;Dias, June Ferraz;Ribeiro, Ciro Alberto Oliveira;Azevedo, Juliana de Souza;
Brazilian Journal of Oceanography , 2011, DOI: 10.1590/S1679-87592011000200005
Abstract: there are few environmental studies using biomarkers for the species atherinella brasiliensis in brazil. in the present work, the presence of hepatic histopathological lesions and nuclear abnormalities in erythrocytes were investigated in a. brasiliensis from lamberto, a beach under influence of domestic wastes and marine activities. for comparison, fish were also sampled in puruba, a non-polluted beach, located in the northeastern of s?o paulo state. the frequency of lesions found in liver was in higher numbers in individuals from lamberto than puruba beach. the most critical injuries observed in a. brasiliensis were the presence of necrotic areas, leucocytes infiltration and piknotic nucleus. a high occurrence of cells with vacuolization was also observed. the hepatic lesion index of the fish from lamberto beach showed significant high values (iorg=13) when compared with fish from puruba beach (iorg=7) suggesting the influence of the several human activities in the studied site. notched and blebed nucleous were observed in this study, and significant differences were found between the studied sites. however, these differences did not reflect the total nuclear alterations.
Growth of the Silverside Atherinella brasiliensis in Tramandaí Estuary, Southern Brazil (Actinopterygii: Atherinopsidae)
Bervian, Giovana;Fontoura, Nelson F.;
Neotropical Ichthyology , 2007, DOI: 10.1590/S1679-62252007000400008
Abstract: the growth of atherinella brasiliensis (quoy & gaimard, 1824) was studied through monthly samples taken at tramandaí lagoon, imbé county, rio grande do sul, brazil. animals were captured using a beach seine net. length-weight relationships and age- growth curves for males and females were adjusted. the growth parameters of the von bertalanffy growth formulae are linf=16.0 and k=0.883 for males and linf=17.0 and k=0.825 for females. first reproduction occurred one year after recruitment. once reaching maturity, adults of a. brasiliensis reproduced once more in the next spring with two-year-olds and disappeared soon after from size frequency distributions. a few captured animals showed a size compatible with an age of three years.
Recrutamento do peixe-rei, Atherinella brasiliensis (Quoy & Gaimard) (Atheriniformes, Atherinopsidae), na margem continental da Baía de Sepetiba, Rio de Janeiro, Brasil
Pessanha, André Luiz Machado;Araújo, Francisco Gerson;
Revista Brasileira de Zoologia , 2001, DOI: 10.1590/S0101-81752001000400021
Abstract: the silverside, atherinella brasiliensis (quoy & gaimard, 1824), a resident species of the shallows of bays, estuaries and coastal lagoons, was studied during two annual cycles, using beach seines (july 1996 to june 1998), in the continental margin of the sepetiba bay, aiming to assess recruitment and distribution patterns. a wide recruitment period, with young-of-the-year appearing from early spring to early autumn, was shown, with peaks of juveniles (total length-lt = 10-30 mm) being recorded in two periods of the year; one in november and another in march. the highest abundances, of both juvenile and adults, were recorded in coroa grande and itacuru?á, sites located in the outer bay, during the whole summer, with significant differences were found. in spite of not having been found any statistically significant relationship between the environmental factors and the occurrence of this species, a trend of higher abundance in colder and more saline waters was detected. high values of growth coefficient (k = 0.93) and low asymptotic lenght (l∞ = 11.6 cm) indicated that this species shows a high growth rate and short life cycle, with life span of 3.09 years, in this system.
Uso do manguezal de Guaratiba, Baía de Sepetiba, Rio de Janeiro, pelo peixe-rei Atherinella brasiliensis (Quoy & Gaimard) (Atheriniformes, Atherinopsidae)
Neves, Leonardo M.;Pereira, Hamilton H.;Costa, Marcus R. da;Araújo, Francisco G.;
Revista Brasileira de Zoologia , 2006, DOI: 10.1590/S0101-81752006000200017
Abstract: fish and environmental variables were sampled in a mangrove area from sepetiba bay to assess the role of this system in life cycle of the silverside atherinella brasiliensis (quoy & gaimard, 1824). standardized monthly sampling using beach seines were conducted at five sites, between august, 2002 and july, 2003 in daily (day/night) basis, with environmental variables being taken at each site. the highest numerical abundance was recorded in the intermediate sample area in the mangrove channel and the lowest in the innermost site. the highest weight occurred in the outermost site near to the sea connection. numerical abundance was directly correlated with temperature and salinity, and weight with salinity and dissolved oxygen (p < 0.05). size ranged from 10 to 160 mm tl, with modes of 40-50 mm tl occurring all over the year in all sites. recruitment occurred all year round but peaks (tl = 30 mm) in october-december, 2002 and july, 2003 were recorded afterwards the records of larger fishes (september, 2002 and june, 2003) mainly in the outermost site. the largest fishes concentrated in the sandy substrate of the outermost sites, areas more suitable for a. brasiliensis spawning, with recruits dispersing all over the mangrove areas, which are used as rearing grounds. the affinity for highly structured habitats in mangrove and the capacity to use efficiently semi-closed systems was confirmed for a. brasiliensis in guaratiba mangrove.
Reprodu??o do peixe-rei, Atherinella brasiliensis (Quoy & Gaimard) (Atheriniformes, Atherinidae), em uma planície de maré adjacente à gamboa do Bagua?u, Baía de Paranaguá, Paraná, Brasil
Favaro, Luís Fernando;Lopes, Sabine de C. G.;Spach, Henry Louis;
Revista Brasileira de Zoologia , 2003, DOI: 10.1590/S0101-81752003000300022
Abstract: the present study investigated the reproductive biology of silverside, atherinella brasiliensis (quoy & gaimard, 1825) in a tidal flat of paranaguá bay, littoral of paraná state, brazil. fish were captured monthly from november 1998 to october 1999 by the mean of a seine-net. for each individual, total body length, total weight, sex, and gonadal weight were recorded. gonadal development stages were also defined based on the histological examination of the ovaries and on the visual aspects of the testes. it was defined that the reproductive period of a. brasiliensis extends from june to december, based on he analyses of individual gonadosomatic index (gsi) values distribution in relation to the sampling periods, on the monthly variation of the gsi mean values (curve of maturation), both for males and females, and on the monthly variation of the relative frequencies of the female maturation stages. during this period, matured, partially spawned and spent females were found in higher frequencies in comparison to the other months. the sizes at first maturation were defined as 7,61cm and 6,92cm for females and males, respectively.
Reprodu o do peixe-rei, Atherinella brasiliensis (Quoy & Gaimard) (Atheriniformes, Atherinidae), em uma planície de maré adjacente à gamboa do Bagua u, Baía de Paranaguá, Paraná, Brasil
Favaro Luís Fernando,Lopes Sabine de C. G.,Spach Henry Louis
Revista Brasileira de Zoologia , 2003,
Abstract: The present study investigated the reproductive biology of silverside, Atherinella brasiliensis (Quoy & Gaimard, 1825) in a tidal flat of Paranaguá Bay, littoral of Paraná State, Brazil. Fish were captured monthly from November 1998 to October 1999 by the mean of a seine-net. For each individual, total body length, total weight, sex, and gonadal weight were recorded. Gonadal development stages were also defined based on the histological examination of the ovaries and on the visual aspects of the testes. It was defined that the reproductive period of A. brasiliensis extends from June to December, based on he analyses of individual gonadosomatic index (GSI) values distribution in relation to the sampling periods, on the monthly variation of the GSI mean values (Curve of Maturation), both for males and females, and on the monthly variation of the relative frequencies of the female maturation stages. During this period, matured, partially spawned and spent females were found in higher frequencies in comparison to the other months. The sizes at first maturation were defined as 7,61cm and 6,92cm for females and males, respectively.
Correction of the weight and length for juveniles Atherinella brasiliensis (Actinopterygii: Atherinopsidae) after fixation in formalin and preservation in ethanol
Melo, Marcelo T.;Saturnino, Cíntia;Santos, Joaquim N. S.;Vasconcellos, Ruan M.;Cruz-Filho, Antonio G.;Araújo, Francisco G.;
Zoologia (Curitiba) , 2010, DOI: 10.1590/S1984-46702010000600009
Abstract: the present study compared losses of weight and length in specimens of atherinella brasiliensis (quoy & gaimard, 1825) after fixation in formalin 10% during ten days, and posterior preservation in ethanol 70% for 45 days, in two solvents: freshwater and marine water. additionally, correction factors were proposed to calculate the correction for weight and length from preserved specimens. the specimens were weighted and measured after collection (fresh), and with 10, 20, 27, 34, 41 and 55 days of fixation plus preservation. the largest losses in weight occurred during the first 20 days (10.35 ± 0.31% - freshwater; 11.29 ± 0.44% - marine water), continuing with lesser intensity up to the 27th day in freshwater dilution, and up to the 34th day in marine water dilution. weight losses stabilized by the 34th day for both freshwater (11.77 ± 0.33%) and marine water (13.62 ± 0.41%). the largest losses in the total length for the two methods were also observed in the first 20 days (7.42 ± 0.27% - freshwater; 9.76 ± 0.26 - marine water), stabilizing after the 27th day in freshwater (8.60 ± 0.26%) and 20th day in marine water (9.76 ± 0.26%). the losses of weight and total length were significantly dependent on fish size, with smaller individuals suffering the most significant losses. complete regression equations were proposed for the retro-calculation of fresh weight and total length from the preserved specimens for freshwater (wfresh = 1.0536wp + 0.0416; tlfresh = 0.9588tlp + 5.8437) and marine water (wfresh = 1.0868wp + 0.0451; tlfresh = 0.8621tlp + 10.425).
Description of Atherinella brasiliensis (Quoy & Gaimard, 1825) (Atheriniformes: Atherinopsidae) larvae from the Jaguaribe River estuary, Itamaracá island, Northeastern Brazil
Fran?a, Elton J.;Severi, William;Castro, Maviael F.;Medeiros, Tatiane N.;El-Deir, Ana Carla A.;
Neotropical Ichthyology , 2007, DOI: 10.1590/S1679-62252007000300016
Abstract: the present study describes the external morphology and morphometry of the initial development of atherinella brasiliensis, and contributes toward broadening knowledge on its biology. a total of 88 larvae and 14 juveniles were used to characterize the morphological development and analyze body proportions. fish with standard lengths (sl) from 1.4 to 77 mm were used in the study. larvae hatch at an average of 1.4 mm sl. in the preflexion stage, the larval body is enveloped by a finfold, which begins behind the head. pectoral fins are the first to be formed and preflexion larvae have four characteristic dendritic chromatophores on the head. the flexion stage begins at an average of 4.4 mm sl; dorsal and anal fins already exhibit pterygiophores and a terminal, somewhat up-turned mouth. at 6.8 mm sl, the flexion stage ends. in the postflexion stage, larvae present greater ossification of the dorsal and anal fin rays, exhibit pelvic fin buds and a darkening of lateral pigmentation. at an average of 8.8 mm sl, head pigmentation intensifies and pelvic fins exhibit conspicuous ossifying rays. larvae at 11.8 mm sl have all fins formed; the second dorsal fin is the last to be formed at an insertion point posterior to the anal fin. the juvenile period begins at approximately 12 mm sl. at this stage, a. brasiliensis has an anal fin located at the median portion of the body and the posterior end of pectorals surpasses the origin of pelvic fins, which are located at the midpoint between the pectoral and anal fins. scales are present on the dorsal-lateral region behind the head. the morphological features of a. brasiliensis herein described allow an adequate identification of its larvae and differentiate them from hemiramphid and other atheriniform larvae, thus broadening knowledge on the larval biology of the species.
Estrutura da popula??o e aspectos reprodutivos do peixe-rei Atherinella brasiliensis (Quoy & Gaimard) (Atheriniformes, Atherinopsidae) em áreas rasas do complexo estuarino de Paranaguá, Paraná, Brasil
Fávaro, Luís F.;Oliveira, Elton C. de;Verani, Nelsy F.;
Revista Brasileira de Zoologia , 2007, DOI: 10.1590/S0101-81752007000400036
Abstract: the population structure and reproductive aspects of atherinella brasiliensis (quoy & gaimard, 1825) had been analyzed monthly from may 2000 to april 2001 in eight points of shallow areas of the estuarine complex paranaguá. the environment analyzes of the parameters ph, dissolved oxygen, transparency and salinity of the water suggest the existence of an increasing environment gradient in the direction north-south highway of the estuary. the temperature of the water evidenced the seasonal variation in the studied system, revealing related with the reproductive process. the peak of reproductive activity was determined for females and male, respectively, in the months of october and september, period where if it verified the ratio of two females for a male. the predominance of young individuals in the estuary occurred in the end of the spring and during the summer, after the reproductive period. the seasonal analyses of length and mass suggest the existence of a cyclical standard of growth to the long of the year, which reflects the reproductive period and the entrance of young individuals in the environment. thus, it is concluded that a. brasiliensis is a resident estuarine species, revealing widely distributed in the estuarine shallow areas, being able to be considered key in evaluations of environmental impact and/or action of handling plans and conservation in estuarine environments.
Examination of spotted sand bass (Paralabrax maculatofasciatus) pollutant bioaccumulation in San Diego Bay, San Diego, California  [PDF]
Chad L. Loflen
PeerJ , 2015, DOI: 10.7717/peerj.213
Abstract: The spotted sand bass (Paralabrax maculatofasciatus) is an important recreational sport and subsistence food fish within San Diego Bay, a large industrialized harbor in San Diego, California. Despite this importance, few studies examining the species life history relative to pollutant tissue concentrations and the consumptive fishery exist. This study utilized data from three independent spotted sand bass studies from 1989 to 2002 to investigate PCB, DDT, and mercury tissue concentrations relative to spotted sand bass age and growth in San Diego Bay, with subsequent comparisons to published pollutant advisory levels and fishery regulations for recreational and subsistence consumption of the species. Subsequent analysis focused on examining temporal and spatial differences for different regions of San Diego Bay.
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