Seeing further into the early steps of the endangered atlantic goliath grouper (Epinephelus itajara): Eye lenses high resolution isotopic profiles reveal ontogenetic trophic and habitat shifts.

Estuarine mangroves are often considered nurseries for the Atlantic Goliath grouper juveniles. Yet, the contributions of different estuarine primary producers and habitats as sources of organic matter during early ontogenetic development remain unclear. Given the species' critically endangered status and protection in Brazil, obtaining biological samples from recently settled recruits in estuaries is challenging. In this study, we leveraged a local partnership with fishers and used stable isotope (C and N) profiles from the eye lenses of stranded individuals or incidentally caught by fishery to reconstruct the trophic and habitat changes of small juveniles. The eye lens grows by the apposition of protein-rich layers. Once these layers are formed, they become inert, allowing to make inferences on the trophic ecology and habitat use along the development of the individual until its capture. We used correlations between fish size and the entire eye lens size, along with estuarine baselines, to reconstruct the fish size and trophic positions for each of the lens layers obtained. We then used dominant primary producers and basal sources from mangrove sheltered, exposed estuarine and marine habitats to construct an ontogenetic model of trophic and habitat support changes since maternal origins. Our model revealed marine support before the juveniles reached 25 mm (standard length), followed by a rapid increase in reliance on mangrove sheltered sources, coinciding with the expected size at settlement. After reaching 60 mm, individuals began to show variability. Some remained primarily supported by the mangrove sheltered area, while others shifted to rely more on the exposed estuarine area around 150 mm. Our findings indicate that while mangroves are critical for settlement, as Goliath grouper juveniles grow, they can utilize organic matter produced throughout the estuary. This underscores the need for conservation strategies that focus on seascape connectivity, as protecting just one discrete habitat may not be sufficient to preserve this endangered species and safeguard its ecosystem functions.

Effects of Probiotic Bacteria Bacillus on Growth Performance, Digestive Enzyme Activity, and Hematological Parameters of Asian Sea Bass, Lates calcarifer (Bloch).

This study was conducted to evaluate different doses of two species of Bacillus (Bacillus licheniformis and Bacillus subtilis), on growth parameters, chemical composition of fish, activity of liver, and digestive enzymes of Asian sea bass. During 8 weeks, juvenile Asian sea bass received diets supplemented with 1 × 103, 1 × 106, and 1 × 109 CFU g-1 probiotic in addition to a control diet without added microorganisms. At the end of the trial, growth indices (total weight, total length, specific growth rate, total weight gain, food conversion ratio, and condition factor), body composition (crude protein, crude lipid, ash, and dry matter), digestive enzymes (protease, lipase, and amylase), liver enzymes [aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP)], immunologic indicators (lysozyme), and hematological parameters [hematocrit (Hct), hemoglobin (Hb), red blood cells (RBCs), white blood cells (WBCs)] were assessed. Asian sea bass receiving diets supplemented with probiotic Bacillus (Bacillus licheniformis and Bacillus subtilis) showed significantly better growth than those fed the basal diet (control). Regarding body composition, total protein levels and dry matter were higher and lipid levels were lower in fish fed the diet containing 1 × 106 CFU g-1 probiotic compared with the control group (P < 0.05). Digestive enzymes (protease, lipase, and amylase) and hematological parameters (RBC, WBC, and Hb) were all highest in fish fed diet supplemented with 1 × 106 CFU g-1 probiotic Bacillus. Also, liver enzymes (AST, ALT, ALP) were lower in fish fed diet supplemented with 1 × 106 CFU g-1 probiotic Bacillus. Being that supplementation of 1 × 106 CFU g-1 of Bacillus in the diet is the dose which delivers the best results.

Shelters influence in dusky grouper culture / Influência de abrigos na criação da garoupa-verdadeira

Environmental enrichment can be an important tool to improve the productive performance of dusky grouper Epinephelus marginatus (Lowe, 1834). The goal of this study was to evaluate the preference for shelters and the effect of the availability of shelters on the productive performance of dusky groupers juveniles in salt water recirculation system. Two trials were conducted, the first one to determine the preference for different types of shelters (rocks, bricks and PVC pipes of different colors) and the second one on the use of shelters, with three treatments (T1 = without shelter; T2 = one shelter per fish and T3 = two shelters per fish). The dusky grouper showed preference for shelters of PVC tubes of brown color. The use of shelters favored better productive performance of the species in salt water recirculation systems.(AU)

O enriquecimento ambiental pode ser uma ferramenta importante para melhorar o desempenho produtivo da garoupa-verdadeira Epinephelus marginatus (Lowe, 1834). O objetivo deste estudo foi avaliar a preferência por abrigos e o efeito da disponibilidade de abrigos sobre o desempenho produtivo de juvenis de garoupa-verdadeira em sistema de recirculação de água salgada. Foram realizados dois ensaios, o primeiro para determinar a preferência por diferentes tipos de abrigos (pedras, tijolos e tubos de PVC de diferentes cores) e o segundo sobre o uso de abrigos, com três tratamentos (T1 = sem abrigo; T2 = um abrigo por peixe e T3 = dois abrigos por peixe). A garoupa-verdadeira mostrou preferência por abrigos de tubos de PVC de cor marrom. O uso de abrigos favoreceu um melhor desempenho produtivo da espécie em sistemas de recirculação de água salgada.(AU)

Shelters influence in dusky grouper culture / Influência de abrigos na criação da garoupa-verdadeira

Environmental enrichment can be an important tool to improve the productive performance of dusky grouper Epinephelus marginatus (Lowe, 1834). The goal of this study was to evaluate the preference for shelters and the effect of the availability of shelters on the productive performance of dusky groupers juveniles in salt water recirculation system. Two trials were conducted, the first one to determine the preference for different types of shelters (rocks, bricks and PVC pipes of different colors) and the second one on the use of shelters, with three treatments (T1 = without shelter; T2 = one shelter per fish and T3 = two shelters per fish). The dusky grouper showed preference for shelters of PVC tubes of brown color. The use of shelters favored better productive performance of the species in salt water recirculation systems.

O enriquecimento ambiental pode ser uma ferramenta importante para melhorar o desempenho produtivo da garoupa-verdadeira Epinephelus marginatus (Lowe, 1834). O objetivo deste estudo foi avaliar a preferência por abrigos e o efeito da disponibilidade de abrigos sobre o desempenho produtivo de juvenis de garoupa-verdadeira em sistema de recirculação de água salgada. Foram realizados dois ensaios, o primeiro para determinar a preferência por diferentes tipos de abrigos (pedras, tijolos e tubos de PVC de diferentes cores) e o segundo sobre o uso de abrigos, com três tratamentos (T1 = sem abrigo; T2 = um abrigo por peixe e T3 = dois abrigos por peixe). A garoupa-verdadeira mostrou preferência por abrigos de tubos de PVC de cor marrom. O uso de abrigos favoreceu um melhor desempenho produtivo da espécie em sistemas de recirculação de água salgada.

Effects of dietary ginkgo biloba leaf extract on growth performance, plasma biochemical parameters, fish composition, immune responses, liver histology, and immune and apoptosis-related genes expression of hybrid grouper (Epinephelus lanceolatus♂ × Epinephelus fuscoguttatus♀) fed high lipid diets.

For thousands of years, leaves from the Ginkgo biloba tree have been a common treatment in Chinese medicine. The present study was conducted to investigate the effects of dietary ginkgo biloba leaf extract (GBE) supplementation on growth performance, plasma biochemical parameters, fish composition, immune responses, liver histology, and immune and apoptosis-related genes expression of hybrid grouper (Epinephelus lanceolatus♂ × Epinephelus fuscoguttatus♀) fed high lipid diets. A basal diet supplemented with GBE at 0, 0.50, 1.00, 2.00, 4.00 and 10.00 g kg-1 was fed to hybrid grouper for 8 weeks. The study indicated that dietary GBE did not improve growth performance and feed utilization but it reduced intraperitoneal fat rate. There were no significant differences in condition factor, viscerosomatic index, hepatosomatic index, spleen index, relative gut length, food intake, protein deposit rate and survival among all groups (P > 0.05). Dietary supplementation with 0.50-4.00 g GBE kg-1 diets effectively increased plasma HDL content and decreased plasma GLU, LDL and TG content in fish. Furthermore, dietary GBE had a significant effect on moisture, crude protein and lipid in the liver, and protein in the whole body of fish (P < 0.05). Dietary supplementation with 0.50-1.00 g GBE kg-1 diets effectively decreased occurrence rates of the hepatocyte swelling, hepatocyte vacuolization, and nuclei shifting to the cellular periphery cytoplasmic vacuolization, meanwhile hepatic antioxidant enzymes (SOD, CAT and T-AOC) activities significantly increased whereas MDA content significantly decreased in fish fed diets supplemented with GBE (P < 0.05). Moreover, dietary GBE up-regulated the expression of antioxidant genes (CAT, GPx and GR), immune-related genes (MHC2 and TLR3) and anti-inflammatory cytokines (IL-10 and TGF-ß1), while dietary supplementation with 0.50-4.00 g GBE kg-1 diets down-regulated apoptosis-related genes (p53, caspase-9, caspase-8 and caspase-3) expression in the head kidney of hybrid grouper. These results indicated that hybrid grouper fed diets supplemented with GBE did not improve growth performance and feed utilization but it had hypolipidemic effects, improved hepatic antioxidant status, maintained normal liver histology and preserved liver function, increased immune-related genes expression and decreased apoptosis-related genes expression in the head kidney of hybrid grouper.

A new species of Anthiadinae (Teleostei: Serranidae) from São Pedro and São Paulo Archipelago, Brazil, Equatorial Atlantic.

A new species of Anthiadinae, Odontanthias cauoh, is described from São Pedro and São Paulo Archipelago (SPSPA), Brazil, Equatorial Atlantic. The new species differs from its only Atlantic congener by a combination of several characters: pectoral-fin rays 20; total gill rakers on first arch 39; vomerine tooth patch with a posterior prolongation; pelvic fin not reaching base of last anal-fin ray; dorsal, anal and pelvic fins scaleless; and coloration (dorsal, anal, and pelvic fins mostly dark red). The record of the new species contributes to increase the fish endemism in SPSPA.

Age and growth of the mutton hamlet Alphestes afer, with a review of the size and age of sex change among epinephelids.

This paper presents results on the age, growth and population structure of a small grouper, the mutton hamlet Alphestes afer, and discusses the observed size and age structure patterns in relation to reproductive strategies among the epinephelids. Ages were determined by examination of sectioned otoliths, which showed a distinct pattern of alternating translucent and opaque zones that formed annually, as validated with tetracycline labelling. The von Bertalanffy growth function was adjusted to the length-at-age data of the males and females, but no significant differences were observed between the resulting parameters. The females, however, were older at given sizes and attained larger sizes and ages, with a maximum observed longevity of 13 years and a total length (LT ) of 26 cm, while the males attained maximum longevities of only 10 years and a 22 cm maximum LT . The LT and age range for the sex change was 16-25 cm and 3-11 years. The total mortality rate (Z) was estimated to be 0·55 for females and 0·82 for males. With the males younger and smaller than the females, this species differed from the pattern commonly observed for protogynous epinephelids. Males had slower growth after maturation, probably due to energy allocation to sperm production during sexual development. This study shows that demography is an important tool to understand the pathways for reproductive strategies in grouper populations.

Performance of common snook and fat snook juveniles at different stocking densities in fresh water / Desempenho de juvenis de robalo-flecha e robalo-peva submetidos a diferentes densidades de estocagem em água doce

The objective of this experiment was to compare survival and growth of fat snook(Centropomusparallelus) and common snook (Centropomusundecimalis), reared in freshwater under different stocking densities. The experiment lasted 251 days. The fish were randomly distributed in cages (1 m x 1 m x 0.8 m), treatments in triplicate, placed inside an earthen pond located in Camboriú (SC). Water quality parameters were measured and were adequate for the species, except for the low temperatures (19.8 ± 3.3 C). Zootechnical parameters were analyzed by a two-way ANOVA (species x density). Concerning growth, total length and condition factor were significantly different between species, and specific growth rate was not significantly different between treatments (0.23% day-1). Nevertheless, there was a significant interaction of species and stocking density in relation to final weight (fat snook 42.4 ± 16.8; 34.5 ± 15.3 e 39.1 ± 18.7 g; common snook 46.2 ± 18.3; 52.8 ± 22.6 e 46.4 ± 18.8 g; for 12.5; 25.0 and 37.5 fish m-³, respectively). Regarding survival, there was also a significantly difference between species (fat snook 90.0 ± 5.9% and common snook 66.3 ± 9.4%). Stocking density significantly affected biomass only (459 ± 74.5 g; 842 ± 100 g; 1,157 ± 293 g, in densities of 12.5; 25.0 e 37.5 fish m-³, respectively). Both species had a positive growth without a clear advantage for common snook, as expected. (AU)

O objetivo deste trabalho foi comparar o desenvolvimento de peixes juvenis de robalo-peva (Centropomus parallelus) e robalo-flecha (Centropomus undecimalis) criados em água doce em diferentes densidades de estocagem, com três réplicas, durante 251 dias. Foram utilizados tanques-rede (1,0 x 1,0 x 0,8 m) no interior de um viveiro escavado no município de Camboriú (SC). Os parâmetros de qualidade da água foram monitorados e permaneceram adequados para as espécies, com exceção da temperatura (19,8 ± 3,3 C). Os parâmetros zootécnicos foram analisados por ANOVA bi-fatorial (espécie x densidade). A taxa de crescimento específico do peso não apresentou diferença significativa entre os tratamentos (0,23% dia-1) e o fator espécie teve efeito significativo apenas no comprimento e no fator de condição. Entretanto, houve interação significativa entre espécie e densidade para o peso (peva 42,4 ± 16,8; 34,5 ± 15,3 e 39,1 ± 18,7 g; flecha 46,2 ± 18,3; 52,8 ± 22,6 e 46,4 ± 18,8 g; para 12,5; 25,0 e 37,5 peixes m-3, respectivamente). Com relação à sobrevivência, a espécie também teve efeito significativo (peva 90,0 ± 5,9% e flecha 66,3 ± 9,4%). A densidade só teve efeito significativo na biomassa. O robalo-peva apresentou maior taxa de sobrevivência em água doce do que o robalo-flecha. O aumento da densidade somente resultou em incremento significativo na biomassa (459 ± 74,5 g; 842 ± 100 g; 1.157 ±293 g, para 12,5; 25,0 e 37,5 peixes m-3, respectivamente). Ambas as espécies apresentaram crescimento,mas sem vantagem nítida do robalo-flecha, como seria esperado.(AU)

Performance of common snook and fat snook juveniles at different stocking densities in fresh water / Desempenho de juvenis de robalo-flecha e robalo-peva submetidos a diferentes densidades de estocagem em água doce

The objective of this experiment was to compare survival and growth of fat snook(Centropomusparallelus) and common snook (Centropomusundecimalis), reared in freshwater under different stocking densities. The experiment lasted 251 days. The fish were randomly distributed in cages (1 m x 1 m x 0.8 m), treatments in triplicate, placed inside an earthen pond located in Camboriú (SC). Water quality parameters were measured and were adequate for the species, except for the low temperatures (19.8 ± 3.3 C). Zootechnical parameters were analyzed by a two-way ANOVA (species x density). Concerning growth, total length and condition factor were significantly different between species, and specific growth rate was not significantly different between treatments (0.23% day-1). Nevertheless, there was a significant interaction of species and stocking density in relation to final weight (fat snook 42.4 ± 16.8; 34.5 ± 15.3 e 39.1 ± 18.7 g; common snook 46.2 ± 18.3; 52.8 ± 22.6 e 46.4 ± 18.8 g; for 12.5; 25.0 and 37.5 fish m-³, respectively). Regarding survival, there was also a significantly difference between species (fat snook 90.0 ± 5.9% and common snook 66.3 ± 9.4%). Stocking density significantly affected biomass only (459 ± 74.5 g; 842 ± 100 g; 1,157 ± 293 g, in densities of 12.5; 25.0 e 37.5 fish m-³, respectively). Both species had a positive growth without a clear advantage for common snook, as expected.

O objetivo deste trabalho foi comparar o desenvolvimento de peixes juvenis de robalo-peva (Centropomus parallelus) e robalo-flecha (Centropomus undecimalis) criados em água doce em diferentes densidades de estocagem, com três réplicas, durante 251 dias. Foram utilizados tanques-rede (1,0 x 1,0 x 0,8 m) no interior de um viveiro escavado no município de Camboriú (SC). Os parâmetros de qualidade da água foram monitorados e permaneceram adequados para as espécies, com exceção da temperatura (19,8 ± 3,3 C). Os parâmetros zootécnicos foram analisados por ANOVA bi-fatorial (espécie x densidade). A taxa de crescimento específico do peso não apresentou diferença significativa entre os tratamentos (0,23% dia-1) e o fator espécie teve efeito significativo apenas no comprimento e no fator de condição. Entretanto, houve interação significativa entre espécie e densidade para o peso (peva 42,4 ± 16,8; 34,5 ± 15,3 e 39,1 ± 18,7 g; flecha 46,2 ± 18,3; 52,8 ± 22,6 e 46,4 ± 18,8 g; para 12,5; 25,0 e 37,5 peixes m-3, respectivamente). Com relação à sobrevivência, a espécie também teve efeito significativo (peva 90,0 ± 5,9% e flecha 66,3 ± 9,4%). A densidade só teve efeito significativo na biomassa. O robalo-peva apresentou maior taxa de sobrevivência em água doce do que o robalo-flecha. O aumento da densidade somente resultou em incremento significativo na biomassa (459 ± 74,5 g; 842 ± 100 g; 1.157 ±293 g, para 12,5; 25,0 e 37,5 peixes m-3, respectivamente). Ambas as espécies apresentaram crescimento,mas sem vantagem nítida do robalo-flecha, como seria esperado.

A novel method to obtain accurate length estimates of carnivorous reef fishes from a single video camera

In the last years, technological advances enhanced the utilization of baited underwater video (BUV) to monitor the diversity, abundance, and size composition of fish assemblages. However, attempts to use static single-camera devices to estimate fish length were limited due to high errors, originated from the variable distance between the fishes and the reference scale included in the scene. In this work, we present a novel simple method to obtain accurate length estimates of carnivorous fishes by using a single downward-facing camera baited video station. The distinctive feature is the inclusion of a mirrored surface at the base of the stand that allows for correcting the apparent or "naive" length of the fish by the distance between the fish and the reference scale. We describe the calibration procedure and compare the performance (accuracy and precision) of this new technique with that of other single static camera methods. Overall, estimates were highly accurate (mean relative error = -0.6%) and precise (mean coefficient of variation = 3.3%), even in the range of those obtained with stereo-video methods.

En los últimos años, los avances tecnológicos permitieron intensificar el uso de estaciones de video fijas para estudiar la abundancia, composición de especies y estructura de tamaños de los ensambles ícticos. Sin embargo, la utilización de una única cámara estática para estimar el tamaño de los peces puede conducir a determinaciones poco exactas, provocadas por la distancia variable entre los peces y la escala de referencia incluida en la escena. En este trabajo presentamos un método novedoso para obtener estimaciones exactas del largo de peces carnívoros, que utiliza una estación de video fija con una única cámara orientada verticalmente. La característica que distingue a este sistema es la inclusión de una superficie espejada en la base del soporte de la cámara que permite corregir la longitud aparente o "naive" en función de la distancia entre los peces y la escala de referencia. En este trabajo describimos el procedimiento de calibración y comparamos el rendimiento de esta técnica (exactitud y precisión) con la de otros métodos que utilizan una única cámara estática. Las estimaciones obtenidas fueron exactas (error relativo promedio = -0,6%) y precisas (coeficiente de variación promedio = 3,3%), en el rango de valores obtenidos con estéreo-video.

A novel method to obtain accurate length estimates of carnivorous reef fishes from a single video camera

In the last years, technological advances enhanced the utilization of baited underwater video (BUV) to monitor the diversity, abundance, and size composition of fish assemblages. However, attempts to use static single-camera devices to estimate fish length were limited due to high errors, originated from the variable distance between the fishes and the reference scale included in the scene. In this work, we present a novel simple method to obtain accurate length estimates of carnivorous fishes by using a single downward-facing camera baited video station. The distinctive feature is the inclusion of a mirrored surface at the base of the stand that allows for correcting the apparent or "naive" length of the fish by the distance between the fish and the reference scale. We describe the calibration procedure and compare the performance (accuracy and precision) of this new technique with that of other single static camera methods. Overall, estimates were highly accurate (mean relative error = -0.6%) and precise (mean coefficient of variation = 3.3%), even in the range of those obtained with stereo-video methods.(AU)

En los últimos años, los avances tecnológicos permitieron intensificar el uso de estaciones de video fijas para estudiar la abundancia, composición de especies y estructura de tamaños de los ensambles ícticos. Sin embargo, la utilización de una única cámara estática para estimar el tamaño de los peces puede conducir a determinaciones poco exactas, provocadas por la distancia variable entre los peces y la escala de referencia incluida en la escena. En este trabajo presentamos un método novedoso para obtener estimaciones exactas del largo de peces carnívoros, que utiliza una estación de video fija con una única cámara orientada verticalmente. La característica que distingue a este sistema es la inclusión de una superficie espejada en la base del soporte de la cámara que permite corregir la longitud aparente o "naive" en función de la distancia entre los peces y la escala de referencia. En este trabajo describimos el procedimiento de calibración y comparamos el rendimiento de esta técnica (exactitud y precisión) con la de otros métodos que utilizan una única cámara estática. Las estimaciones obtenidas fueron exactas (error relativo promedio = -0,6%) y precisas (coeficiente de variación promedio = 3,3%), en el rango de valores obtenidos con estéreo-video.(AU)

Genetic characterization of hatchery populations of Korean spotted sea bass (Lateolabrax maculatus) using multiplex polymerase chain reaction assays.

The spotted sea bass, Lateolabrax maculatus, is an important commercial and recreational fishery resource in Korea. Aquacultural production of this species has increased because of recent resource declines, growing consumption, and ongoing government-operated stock release programs. Therefore, the genetic characterization of hatchery populations is necessary to maintain the genetic diversity of this species and to develop more effective aquaculture practices. In this study, the genetic diversity and structure of three cultured populations in Korea were assessed using multiplex assays with 12 highly polymorphic microsatellite loci; 144 alleles were identified. The number of alleles per locus ranged from 6 to 28, with an average of 13.1. The mean observed and expected heterozygosities were 0.724 and 0.753, respectively. Low levels of inbreeding were detected according to the inbreeding coefficient (mean FIS = 0.003-0.073). All hatchery populations were significantly differentiated from each other (overall fixation index (FST) = 0.027, P < 0.01), and no population formed a separate cluster. Pairwise multilocus FST tests, estimates of genetic distance, mantel test, and principal component analyses did not show a consistent relationship between geographic and genetic distances. These results could reflect the exchange of breeds and eggs between hatcheries and/or genetic drift due to intensive breeding practices. For optimal resource management, the genetic variation of hatchery stocks should be monitored and inbreeding controlled within the spotted sea bass stocks that are being released every year. This genetic information will be useful for the management of both L. maculatus fisheries and the aquaculture industry.

A incorporação de óleo de peixe na dieta pode melhorar o desempenho da garoupa-verdadeira Epinephelus marginatus? / Can fish oil incorporation in diet improve the growth performance of dusky grouper Epinephelus marginatus?

This study evaluated the growth performance of dusky grouper fed with different fish oil proportion incorporated in a commercial diet (CD) with 8.8% Crude Lipid (CL). Diet 1 = CD with 0% oil; diet 2 = CD with 4% oil; and diet 3 = CD with 8.8% oil. Ninety fishes ranging 29.2 ± 1.3 g and 12.2 ± 0.7 cm were divided in nine 40 gal tanks, with ten fishes in each tank, three replicates to each diet, along 90 days. Waters parameters (temperature, oxygen level, total ammonia and salinity) were maintained at specific ranges for the species. The 4% fish oil incorporation on dusky grouper diet provides better performance results comparing with fish feeds with distinct energetic levels.(AU)

Avaliou-se o desempenho da garoupa-verdadeira submetida à dieta comercial (8,8% de extrato etéreo) com incorporação de óleo de peixe em três diferentes proporções: dieta 1 = ração comercial sem acréscimo de óleo; dieta 2 = ração comercial acrescida com 4% de óleo e dieta 3 = ração comercial acrescida com 8% de óleo. Exemplares com 29,2 ± 1,3 g e 12,2 ± 0,7 cm foram distribuídos em nove tanques (150 L, 10 peixes tanque-1) e alimentados com as três dietas experimentais por 90 dias. As variáveis de qualidade de água (temperatura, oxigênio dissolvido, amônia total e salinidade) foram mantidas dentro da faixa recomendada para a espécie. O acréscimo de 4% de óleo de peixe na ração utilizada para a garoupa-verdadeira proporcionou resultados superiores de desempenho quando comparada à rações com distintos teores energéticos.(AU)

A incorporação de óleo de peixe na dieta pode melhorar o desempenho da garoupa-verdadeira Epinephelus marginatus? / Can fish oil incorporation in diet improve the growth performance of dusky grouper Epinephelus marginatus?

This study evaluated the growth performance of dusky grouper fed with different fish oil proportion incorporated in a commercial diet (CD) with 8.8% Crude Lipid (CL). Diet 1 = CD with 0% oil; diet 2 = CD with 4% oil; and diet 3 = CD with 8.8% oil. Ninety fishes ranging 29.2 ± 1.3 g and 12.2 ± 0.7 cm were divided in nine 40 gal tanks, with ten fishes in each tank, three replicates to each diet, along 90 days. Waters parameters (temperature, oxygen level, total ammonia and salinity) were maintained at specific ranges for the species. The 4% fish oil incorporation on dusky grouper diet provides better performance results comparing with fish feeds with distinct energetic levels.

Avaliou-se o desempenho da garoupa-verdadeira submetida à dieta comercial (8,8% de extrato etéreo) com incorporação de óleo de peixe em três diferentes proporções: dieta 1 = ração comercial sem acréscimo de óleo; dieta 2 = ração comercial acrescida com 4% de óleo e dieta 3 = ração comercial acrescida com 8% de óleo. Exemplares com 29,2 ± 1,3 g e 12,2 ± 0,7 cm foram distribuídos em nove tanques (150 L, 10 peixes tanque-1) e alimentados com as três dietas experimentais por 90 dias. As variáveis de qualidade de água (temperatura, oxigênio dissolvido, amônia total e salinidade) foram mantidas dentro da faixa recomendada para a espécie. O acréscimo de 4% de óleo de peixe na ração utilizada para a garoupa-verdadeira proporcionou resultados superiores de desempenho quando comparada à rações com distintos teores energéticos.

Influência da salinidade no desenvolvimento e relação peso-comprimento do robalo-peva / Salinity influence on development and weight-length relationship of the fat snook

Foi investigado se as mudanças sazonais na salinidade, temperatura, pH e transparência da água contribuem ao desenvolvimento de Centropomus parallelus em ambientes estuarinos. O trabalho foi realizado na Baía de Guaratuba, Paraná, em 2007 e 2008, onde, os indivíduos com comprimento de 15,0-214,0 mm ocupam, ao longo do ano, as áreas rasas e vegetadas. Constatou-se que a abundância da espécie não se associa à salinidade, temperatura, pH ou transparência da água, mas que o tamanho dos indivíduos relaciona-se a essas variáveis. Estima-se que são as oscilações nas variáveis abióticas que propiciam condições favoráveis ao crescimento, pois em cada faixa de salinidade alguma fase de desenvolvimento é contemplada. Associando-se dados de tamanho individual e época de ocorrência a resultados de crescimento de C. parallelus em cultivos experimentais, estima-se que, neste estuário, o robalo-peva desova no final do verão/início do outono, época de maior influência marinha na Baía; que a eclosão dos ovos ocorre sob salinidade alta; e que juvenis crescem durante a progressiva redução da salinidade, característica da proximidade do verão, sob forte aporte fluvial. Adicionando-se aos indivíduos coletados nas cabeceiras da Baía outros pré-adultos e adultos provenientes da pesca amadora, a relação peso/comprimento foi PT = 0,00002.CT2,85 (n = 1.125) com sexos reunidos; PT = 0,00001.CT2,97 (n = 185) apenas em machos adultos; e PT =0,000007.CT3,04 (n = 445) apenas em fêmeas adultas. A diferença entre coeficientes segundo o sexo deve-se à variação no peso dos ovários durante a maturação, maior que dos testículos.(AU)

It was investigated if the seasonal changes in salinity, temperature, pH and water transparency contribute to Centropomus parallelus development in estuaries. The study was performed in 2007 and 2008 at the Guaratuba Bay, Southern Brazil, where individuals 15.0-214.0 mm occupy shallow waters along the year. No relationship between fish abundance and the salinity, temperature, pH or water transparency levels was observed, however salinity was related to the individual size. Because each level of salinity coincides with a particular length of fish, it is concluded that both temporal and spatial environmental changes are favorable to the C. parallelus growth in the headwaters of the estuary. Comparing the seasonal distribution of individual sizes with data on the C. parallelus growth in aquaculture it is estimated that in Guaratuba the fat snook spawns in late summer/early autumn, when the marine influence is stronger; their eggs hatch in high salinity; and juveniles develop simultaneously to the summer salinity decline, during the rainy season, when the rivers influence increases. Data on juveniles added to those coming from recreational fishing performed around the Bay, males plus females, originated the weight/length relationship TW = 0.00002.TL2.85 (n = 1,125); considering males only, TW = 0.00001.TL2.97 (n = 185); and considering females only, TW = 0.000007.TL3.04 (n = 445). Different coefficients between sexes are due to the gonads weight changes, higher in females than in males.(AU)

Rendimento de carcaça, composição do filé e análise sensorial do robalo-peva de rio e de mar / Body yield, fillet composition and sensory evaluation of river and sea fat snook

O robalo-peva é um peixe nativo do Brasil com alto valor comercial, encontrado em águas marinhas e em água doce. O presente estudo foi realizado para avaliar características de rendimento, composição e análise sensorial do robalo-peva de rio e de marna região do Vale do Ribeira, SP. Foram coletados nove peixes de cada ambiente e utilizados para análise do rendimento de carcaça, análise de composição do filé e avaliação sensorial pelo teste de diferença triangular (P<0,05). Não houve diferença para rendimento do peixe eviscerado, tronco limpo ou filé, entretanto, os peixes de rio apresentaram maior fator de condição que os de mar. O rendimento de filé foi alto, com média geral de 43,88 ± 2,47%. Na análise de composição centesimal do filé verificou-se maior valor de lipídios para os peixes de rio e maior valor de proteína para os de mar. Os valores de lipídios foram 2,51 ± 0,50% e 0,20 ± 0,14%, respectivamente, para os peixes de rio e de mar. O perfil de ácidos graxos do filé foi semelhante entre exemplares dos dois locais, com exceção de dois ácidos graxos saturados. Foi possível diferenciar o filé dos robalos dos dois ambientes pela análise sensorial. Conclui-se que o robalo-peva coletado no rio e no mar, no Vale do Ribeira, possui similar rendimento de carcaça e perfil de ácidos graxos do filé, mas diferenças na composição centesimal, principalmente no teor de lipídios, o que pode ter contribuído para a diferenciação dos robalos na análise sensorial.(AU)

The fat snook is a brazilian native fish with high market value, found in marine water and in fresh water. The present study was carried out to evaluate river and sea fat snook characteristics of yield, composition and sensory evaluation, in Vale do Ribeira region, SP. Nine fish was collected from each environment and employed for body yield analysis, fillet composition analysis and sensory evaluation by the difference triangle test (P<0.05). There was no difference for yield of gutted fish, fish clean trunk or fillet, however river fish presented higher condition factor than sea fish. Fillet yield was high with overall average of 43.88 ± 2.47%. In the analyses of fillet proximate composition, it was observed higher lipid value for river fish and higher protein value for marine fish. Lipid value was 2.51 ± 0.50% and 0.20 ± 0.14%, respectively, for river and sea fish. Fillet fat acid profile was similar among individuals of the two places, with exception of two saturated fatty acids. It was possible to differentiate fillet of snook from the two environments by sensory analysis. It is concluded that fat snook collected in the river and in the sea, in Vale do Ribeira, have same body yield and fillet fatty acid profile, but differences in proximal composition, mainlyin the lipid content, what may have contributed for the differentiation of snook in sensory analysis.(AU)

Uma revisão sobre os principais aspectos no cultivo do robalo / A review of major aspects of snook breeding

A piscicultura marinha é uma atividade que apresenta grande tendência de crescimento, sendo que um dos grupos de peixes com grande interesse comercial são os robalos, pertencentes ao gênero Centropomus. Duas espécies desse gênero apresentam características favoráveis para produção em cativeiro, o robalo-peva, C. parallelus, e o robalo flecha, C. undecimalis. Esta revisão tem como objetivo abordar os principais aspectos sobre o cultivo de robalos e suas perspectivas futuras para ampliação da atividade. A tecnologia de criação dos robalos está mais avançada em relação a outras espécies marinhas, entretanto ainda existem alguns gargalos e são necessários mais estudos para a obtenção de melhores índices de desempenho em cativeiro, principalmente durante a fase de engorda. O robalo-peva é a espécie com maior interesse econômico, por apresentar uma boa adaptação ao cultivo em cativeiro e possuir tecnologia de cultivo mais avançada. No caso robalo-flecha a reprodução ainda precisa ser dominada.

Marine fish breeding is an activity that presents great growth trend, in which one of the groups of fish with high commercial interest are the snooks of the genus Centropomus. Two species of this genus show favorable characteristics for captive breeding, the fat snook, C. parallelus, and common snook, C. undecimalis. This review has the objective of approaching the main aspects of snook breeding and their future prospects for the expansion of this activity. The technology for snook breeding is more advanced when compared to other marine species, however there are still some bottlenecks and further studies are necessary to obtain better performance levels in captivity, particularly during the fattening phase. The fat snook is the species with greater economic interest because it shows good adaptation to captive breeding and has more advanced breeding technology. Regarding the common snook, its reproduction has yet to be dominated.

Uma revisão sobre os principais aspectos no cultivo do robalo / A review of major aspects of snook breeding

A piscicultura marinha é uma atividade que apresenta grande tendência de crescimento, sendo que um dos grupos de peixes com grande interesse comercial são os robalos, pertencentes ao gênero Centropomus. Duas espécies desse gênero apresentam características favoráveis para produção em cativeiro, o robalo-peva, C. parallelus, e o robalo flecha, C. undecimalis. Esta revisão tem como objetivo abordar os principais aspectos sobre o cultivo de robalos e suas perspectivas futuras para ampliação da atividade. A tecnologia de criação dos robalos está mais avançada em relação a outras espécies marinhas, entretanto ainda existem alguns gargalos e são necessários mais estudos para a obtenção de melhores índices de desempenho em cativeiro, principalmente durante a fase de engorda. O robalo-peva é a espécie com maior interesse econômico, por apresentar uma boa adaptação ao cultivo em cativeiro e possuir tecnologia de cultivo mais avançada. No caso robalo-flecha a reprodução ainda precisa ser dominada.(AU)

Marine fish breeding is an activity that presents great growth trend, in which one of the groups of fish with high commercial interest are the snooks of the genus Centropomus. Two species of this genus show favorable characteristics for captive breeding, the fat snook, C. parallelus, and common snook, C. undecimalis. This review has the objective of approaching the main aspects of snook breeding and their future prospects for the expansion of this activity. The technology for snook breeding is more advanced when compared to other marine species, however there are still some bottlenecks and further studies are necessary to obtain better performance levels in captivity, particularly during the fattening phase. The fat snook is the species with greater economic interest because it shows good adaptation to captive breeding and has more advanced breeding technology. Regarding the common snook, its reproduction has yet to be dominated.(AU)

Genetic variation and balancing selection at MHC class II exon 2 in cultured stocks and wild populations of orange-spotted grouper (Epinephelus coioides).

Major histocompatibility complex (MHC) molecules play vital roles in triggering adaptive immune responses and are considered the most variable molecules in vertebrates. Recently, many studies have focused on the polymorphism and evolution mode of MHC in both model and non-model organisms. Here, we analyzed the MHC class II exon 2-encoding ß chain in comparison with the mitochondrial Cytb gene and our previously published microsatellite data set in three cultured stocks and four wild populations of the orange-spotted grouper (Epinephelus coioides) in order to investigate its genetic variation and mechanism of evolution. We detected one to four alleles in one individual, suggesting that at least two loci exist in the orange-spotted grouper, as well as a particularly high level of allelic diversity at the MHC loci. Furthermore, the cultured stocks exhibited reduced allelic diversity compared to the wild counterparts. We found evidence of balancing selection at MHC class II exon 2, and codon sites under positive selection were largely correspondent to the protein-binding region. In addition, MHC class II exon 2 revealed significant differences between population differentiation patterns from the neutral mitochondrial Cytb and microsatellites, which may indicate local adaptation at MHC loci in orange-spotted grouper originating from the South China Sea and Southeast Asia.

Spatial distribution and diet of Cephalopholis fulva (Ephinephelidae) at Trindade Island, Brazil

In this study we analyze the population structure and diet of the coney Cephalopholis fulva at Trindade Island, Brazil, through direct observation with SCUBA diving in 11 reef sites around the Island, up to 50 m deep. Diet was based on 77 individuals collected with speargun. Mean population density and biomass were estimated at 29 individuals/100 m² and 13 kg/100 m², respectively. This species is regularly distributed along the costal environments of the Trindade Island, with no significant differences in densities and biomass detected among the different collection habitats (reef crest, reef slope, and reef plateau). However, significantly higher densities were observed micro-habitats with greater structural complexity, which may offer more shelter and food to C. fulva. Four food item groups were identified from the gut contents of C. fulva: Annelida, Crustacea, Teleostei, and Testudinata. It is the first record of predation of the green turtle Chelonia mydas hatchlings by the coney. Trindade Island seems to present the densest concentration of C. fulva in all Brazilian and Caribbean ecosystems inhabited by this species. Scarcity of competitors, predators, and fishing pressure may explain the high densities observed in the Island.

Foram analisadas a estrutura populacional e a dieta do catuá Cephalopholis fulva na Ilha da Trindade, Brasil. Os dados foram obtidos através de censos visuais com mergulho autônomo em 11 locais no entorno da ilha, em profundidades de até 50 m. A dieta e a proporção sexual foram baseadas na análise de 77 indivíduos coletados com arpão. A densidade populacional e biomassa foram estimados em 29 indivíduos/m² e 13 kg/100 m², respectivamente. A espécie apresentou distribuição uniforme nos ambientes costeiros da ilha, não tendo sido registradas diferenças significativa em sua densidade e biomassa entre os diferentes habitats estudados (crista, talude e platô recifal). Entretanto, foi observado preferência por micro-habitats de alta complexidade estrutural. Foram registrados quatro grupos de itens alimentares no conteúdo estomacal de C. fulva: Annelida, Crustacea, Teleostei e Testudinata. É feito aqui o primeiro registro de predação de juvenis da tartaruga-verde (Chelonia mydas) por C. fulva. Trindade parece apresentar os maiores valores de densidade para o catuá, quando comparada a outras localidades do Brasil e Caribe. A escassez de competidores, predadores e a pressão pesqueira são possíveis fatores que podem explicar as altas densidades observadas para C. fulva na Ilha da Trindade.