Heavy Metals in Tissues of Blue Crabs Callinectes danae from a Subtropical Protected Estuary Influenced by Mining Residues.

This short note aims to report in detail a preliminary assessment of the concentrations of Cd, Hg and Pb in tissues of blue crabs Callinectes danae collected from the Cananéia-Iguape-Peruíbe estuarine complex (CIP), in the South of São Paulo State coast, Brazil. In October 2014, blue crabs were collected from CIP. Tissues were removed by dissection and metal determination was performed by GF-AAS and CV-AAS. According to statistical analysis, Pb and Cd concentrations in gills were significantly higher than those found in muscles and hepatopancreas, respectively. There were no significant differences in Hg concentrations between samples. Cd, Hg and Pb concentrations in gills and hepatopancreas were lower than those reported in a previous study performed at CIP. However, Cd concentration in hepatopancreas was higher than the Brazilian limit for consumption and new efforts to monitor Cd concentrations in C. danae tissues must be performed.

Acute metabolic responses of two marine brachyuran crabs to dilute seawater: The aerobic cost of hyper regulation.

Hepatus pudibundus ("flecked box crab") is a stenohaline osmoconfomer, and restricted to marine habitats. Callinectes danae ("swimming crab Dana") lives in coastal/estuarine waters and is a weak hyper regulator. There is no consensus on which strategy is more expensive metabolically face salinity challenges: conformation with higher dependence on cell volume regulation, or hyper regulation, alleviating the need for intense cell volume regulation. Crabs were probed for their acute response to dilute seawater through exposures to salinities 35‰, 30‰, 25‰, and 20‰ for 2, 4, and 6 h. Hemolymph osmolality, lactate, and ions (chloride, sodium, magnesium, potassium) were assayed, as well as muscle water content. Water dissolved oxygen, ammonia, and pH levels were also measured. H. pudibundus conformed for osmolality and displayed increase in muscle hydration along the decrease in salinity down to 25‰, while C. danae efficiently maintained hemolymph osmo ionic stability, consumed more oxygen, acidified more the water, and released more ammonia. In 25‰, both species spent energy: H. pudibundus putatively controlling cell volume, and C. danae regulating hemolymph concentrations. In 20‰, H. pudibundus closed itself, avoiding the contact of the interface epithelia with the external environment and producing much lactate, whereas C. danae spent more energy (aerobic) in extracellular osmo ionic stability. Under these conditions, anisosmotic extracellular regulation (together with additional cell volume regulation) is more oxygen consuming than osmoconformation with a putatively more intense challenge to cell volume. The exposure to hyposalinity limits the occupation of estuarine environments by H. pudibundus in short and middle term.

Differential effects of cobalt ions in vitro on gill (Na+, K+)-ATPase kinetics in the Blue crab Callinectes danae (Decapoda, Brachyura).

We used the gill (Na+, K+)-ATPase as a molecular marker to provide a comprehensive kinetic analysis of the effects of Co2+in vitro on the modulation of K+-phosphatase activity in the Blue crab Callinectes danae. Co2+ can stimulate or inhibit K+-phosphatase activity. With Mg2+, K+-phosphatase activity is almost completely inhibited by Co2+. Co2+ stimulates K+-phosphatase activity similarly to Mg2+ although with a ≈4.5-fold greater affinity. At saturating Mg2+ concentrations, Mg2+ displaces bound Co2+ from the Mg2+-binding site in a concentration dependent manner, but Co2+ cannot displace Mg2+ from its binding site even at millimolar concentrations. Saturation by Co2+ of the Mg2+ binding site does not affect pNPP recognition by the enzyme. Substitution of Mg2+ by Co2+ slightly increases enzyme affinity for K+ and NH4+. Independently of Mg2+, inhibition by ouabain or sodium ions is unaffected by Co2+. Investigation of gill (Na+, K+)-ATPase K+-phosphatase activity provides a reliable tool to examine the kinetic effects of Co2+ with and without Na+ and ATP. Given that the toxic effects of Co2+ at the molecular level are poorly understood, these findings advance our knowledge of the mechanism of action of Co2+ on the crustacean gill (Na+, K+)-ATPase.

Pate de siri com sal de ervas: uma nova alternativa de alimento saudável / Crab pate with herb salt: a new alternative of healthy food

O objetivo desta pesquisa foi investigar a aceitação sensorial de duas formulações de patê de siri com teor reduzido de cloreto de sódio e substituição por sal de ervas. Duas formulações foram desenvolvidas com os mesmos ingredientes básicos, mas diferentes quantidades de sais adicionados. A formulação F1 com sal de ervas e redução de 80% de cloreto de sódio, e a formulação F2 com sal marinho. A avaliação sensorial foi realizada para determinar a aceitabilidade geral, para isso, foram submetidos ao teste de aceitação global, perfil de características e intenção de compra. A substituição do cloreto de sódio pelo sal de ervas foi considerado uma alternativa viável, visto que apresentou uma boa aceitação global, além de ter apresentado intenção de compra de 30% entre provadores adultos não treinados.

Redução de cloreto de sódio em patê de siri utilizando sal de ervas / Reduction of sodium chloride in siri patê using herbal salt

O objetivo deste estudo foi desenvolver um patê de siri utilizando sal de ervas como alternativa para a redução do cloreto de sódio. Para isso, foram preparadas duas formulações, a formulação F1 com sal de ervas, com redução de 80% de cloreto de sódio e a formulação F2 com sal marinho. Para caracterização do produto, foram determinados a composição centesimal, inocuidade e a composição nutricional. Os resultados obtidos mostraram que a formulação F1 apresentou menores teores de sódio e potássio, bem como, menor valor calórico. Com relação a composição nutricional, o patê de siri oferecerá ao consumidor uma alternativa de produto com elevado teor de proteína e baixa caloria, característico de um alimento saudável. Quanto aos padrões microbiológicos, ambas as formulações se encontraram dentro dos parâmetros estabelecidos pela legislação vigente. De fato, a substituição de cloreto de sódio por "sal de ervas", é uma excelente alternativa para a redução do teor de sal nos alimentos.

Crecimiento del cangrejo Callinectes danae (Decapoda: Portunidae) de la Isla de Margarita, Venezuela

Dana Swimming crab growth Callinectes danae (Decapoda: Portunidae) from Margarita Island, Venezuela. Callinectes danae is a common species captured with crab traps in nearby areas of coastal lagoons in Margarita Island. Although its considerable economic importance as a fishery resource, few studies have been done on population dynamics and its fishery potential in local coastal environments to support decision making in fishery administration. We present growth pattern details of Callinectes danae to better estimate its population size and exploitation feasibility. For this, we analyzed a total of 3 623 specimens that were Wonthly captured in crab pots by artisanal fishermen in Las Marites lagoon, from October 2007 to September 2008. The length-weight ratio was determined, and growth parameters estimated from both length and weight curves of the von Bertalanffy model. The general sex ratio showed no significant difference between males and females (χ2=0.04, p>0.05). However, values of slopes b between males and females were significantly different (ts=2.75, p<0.05), as well as intercepts a (ts=2.44, p<0.05). Thus, the length-weight ratio was determined separately: W=7.48e-5*L2.98 for males and W=1.21e-4*L2.87 for females, indicating a negative allometric growth in both sexes. Growth parameters were established as: L∞=134.80mm, W∞=166.04g and k=0.86/yr for males; L∞=122.35mm, W∞=118.45g and k=0.63/yr for females. Lifespan was estimated at 3.05 years for males and 4.24 years for females. We concluded that Callinectes danae is a species with short lifespan and moderately rapid growth. The coefficient of variation values (CV), of the phi-prime growth performance index (ؒ), showed a different growth pattern compared to those obtained in other regions. We propose that a management strategy will be the periodical review of the minimum capture size for fishing area, after the great variability found in growth parameters. Rev. Biol. Trop. 59 (4): 1525-1535. Epub 2011 December 01.

Las especies del género Callinectes sostienen pesquerías importantes en varias partes del mundo. En el occidente de Venezuela, Callinectes sapidus es capturado con palangre y sostiene una pesquería artesanal importante en el Lago de Maracaibo; mientras que en la Isla de Margarita, Callinectes danae es capturado con nasa en zonas cercanas a lagunas costeras y su pesca está limitada por la oferta y la demanda. Estos recursos son de considerable importancia económica entre los crustáceos comestibles; sin embargo, pocos estudios han sido reportados sobre la dinámica poblacional y potencialidad pesquera en ambientes costeros de Venezuela que contribuyan a la toma de decisiones en la administración pesquera. En este documento se presenta información de los parámetros de crecimiento del cangrejo Callinectes danae Smith, 1869, con el fin de obtener un conocimiento detallado del patrón de crecimiento y lograr estimaciones más precisas sobre el tamaño de la población y su disponibilidad para la explotación. Se analizó una muestra constituida por 3 623 ejemplares capturados con nasa cangrejera por la flota artesanal, entre octubre 2007 y septiembre 2008. Se estableció la relación longitud-peso y se estimaron los parámetros de crecimiento de las curvas en longitud y peso del modelo de von Bertalanffy. La proporción sexual global mostró que no existe diferencia significativa entre machos y hembras (χ2=0.04, p>0.05). Los valores de las pendientes b entre machos y hembras presentaron diferencias significativas (ts=2.75, p<0.05) igualmente los interceptos a (ts=2.44, p<0.05); por lo que se estableció la relación longitud-peso por separado: P=7.48e-5*L2.98 para machos y P=1.21e-4*L2.87 para hembras, evidenciándose un crecimiento alométrico negativo en ambos sexos. Los parámetros de crecimiento quedaron establecidos en: L∞=134.80mm, P∞=166.04g y k=0.86/año para machos; L∞=122.35mm, P∞=118.45g y k=0.63/año para hembras. La longevidad fue de 3.05 años para machos y 4.24 años para hembras. Se concluye que Callinectes danae es una especie de vida corta con crecimiento moderadamente rápido, y los valores del coeficiente de variación (CV) del índice de crecimiento phi prima (ؒ) demostraron diferencia de los patrones de crecimiento obtenidos en otras regiones. Como medida de manejo se recomienda considerar la talla mínima de captura por zona de pesca y revisar periódicamente las normativas, debido a la gran variabilidad en el crecimiento.