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Efectos letales y subletales de dos plaguicidas sobre las especies Uca uruguayensis y Chasmagnathus granulata,(Cangrejal Bonaerense)
No full textFil: Rodriguez, Enrique Marcelo. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina
Efectos letales y subletales de dos plaguicidas sobre las especies Uca uruguayensis y Chasmagnathus granulata,(Cangrejal Bonaerense)
Get PDFFil: Rodriguez, Enrique Marcelo. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina
Endocrine disruption by pollutants and effects on progeny
No full textAs mentioned in Chapter 10, hormonally-regulated functions of crustaceans have been reviewed during the last years by several authors. Main endocrine-regulated processes of crustaceans involve moulting, reproduction, glycemia levels, and pigment migration, among others. Several pollutants, such as pesticides, alkylphenols, polychlorinated biphenyls, hydrocarbons, and heavy metals, can interfere with these processes, therefore acting as endocrine-disrupting compounds (ECDs) on crustaceans, as reviewed by several authors (LeBlanc 2007, Rodríguez et al. 2007, deFur et al. 1999). The hyperglycemic crustacean hormone (CHH) belongs to a highly diversified family of peptide hormones, secreted by the sinus gland at the eyestalks (Nagaraju 2011, Fingerman 1997). This hormone has been considered as the “stress hormone” of crustaceans (Chang et al. 1999). In some cases, a hyperglycemic response has been observed following exposure to cadmium (Reddy et al. 2009), but an eventual inhibition of the CHH synthesis has also been reported (Reddy et al. 1996). Hyperglycemia caused by heavy metals in shrimps also showed dependence on both the time of exposure and concentration (Lorenzon et al. 2000). An inhibition of moulting by several estrogenic compounds, as well as by testosterone, antiandrogens, antiestrogens, and some pesticides, has been reported in daphnids and copepods (LeBlanc 2007, Andersen et al. 2001, Zou and Fingerman 1997). Besides, evidence about a possible antagonism of these compounds with the transductional pathway of ecdysone at target tissues has been provided (Mu and LeBlanc 2002a). Juvenoid compounds, such as methoprene and JHIII have also inhibited moulting, perhaps interfering with the stimulating effect of the juvenoid hormone methyl farnesoate (Olmstead and LeBlanc 2001). Regarding reproduction, several estrogenic compounds, both natural and synthetic, as well as some juvenoids and ecdysteroids, have shown to exert an abnormal stimulation on several aspects of crustacean reproduction. Observed effects were mainly the abnormal development of secondary sexual characters in both sexes, and a shift to all-female or allmale broods. These effects were observed in daphnids (Dodson et al. 1999, Olmstead and LeBlanc 2000), copepods (Andersen et al. 1999), and amphipods (Brown et al. 1999, Watts et al. 2002).Fil: Rodriguez, Enrique Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; Argentina. Universidad de Buenos Aires. Facultad de Cs.exactas y Naturales. Departamento de Biodiversidad y Biologia Experimental. Laboratorio de Fisiologia de Crustáceos; ArgentinaFil: Medesani, Daniel Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; Argentina. Universidad de Buenos Aires. Facultad de Cs.exactas y Naturales. Departamento de Biodiversidad y Biologia Experimental. Laboratorio de Fisiologia de Crustáceos; ArgentinaFil: López Greco, Laura S.. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental. Laboratorio de Biología de la Reproducción y Crecimiento de Crustáceos Decápodos; Argentin
Endocrine disruption in crustaceans: New findings and perspectives
No full textA significant advance has been made, especially during the last two decades, in the knowledge of the effects on crustacean species of pollutants proven to be endocrine disruptors in vertebrates. Such effects have been also interpreted in the light of recent studies on crustacean endocrinology. Year after year, the increased number of reports refer to the effects of endocrine disruptors on several processes hormonally controlled. This review is aimed at summarizing and discussing the effects of several kinds of endocrine disruptors on the hormonal control of reproduction (including gonadal growth, sexual differentiation, and offspring development), molting, and intermediate metabolism of crustaceans. A final discussion about the state of the art, as well as the perspective of this toxicological research line is given.Fil: Rodriguez, Enrique Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; Argentin
Effect of protein source on growth of early juvenile redclaw crayfish Cherax quadricarinatus (Decapoda, Parastacidae)
Get PDFWe examined the effect of dietary protein sources on survival and growth of early juvenile C. quadricarinatus. Five isoproteic (35%) and isocaloric diets containing various proportions of fish meal:soybean meal as protein sources were assayed. Fishmeal was replaced by soybean meal as a protein source at 0, 25, 50, 75 or 100% of the protein content. Survival and weight gain were determined after 90 days. The content of protein and lipids in the hepatopancreas and abdominal muscle of surviving animals were determined. The highest weight gain was observed with the replacement of 50% of fish meal by soybean meal, this weight gain was significantly higher than that of diets having only one protein source. There were no significant differences in protein content for either the hepatopancreas and muscle among all diets. Diets with 50% or 25% soy meal produced higher lipid levels in the hepatopancreas, while the replacement of fish meal by soy meal in the 50% and 75% diets showed the highest lipid levels in muscle. Based on results of this study, for culture purposes, and considering the high cost of fish meal, replacing 50% of the protein content of a fish meal diet with soybean meal would yield the best growth at the lowest cost.Fil: Gutiérrez, María Laura. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Rodriguez, Enrique Marcelo. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
Substrate selection and effect of different substrates on survival and growth of juveniles of the freshwater crayfish Cherax quadricarinatus (von Martens 1868) (Decapoda, Parastacidae)
Get PDFSurvival and growth of juveniles of the Australian freshwater crayfish Cherax quadricarinatus were evaluated in aquaria with four different substrates covering their bottom. The four substrates were plastic mesh, small stones, fine sand and bare glass without cover (control group). Two size classes of juveniles were evaluated: recently hatched or early (*0.02 g of body weight) and pre-fattening or advanced (*1 g of body weight). A group of twelve early or ten advanced juveniles were placed in each of the 24 aquaria. Each substrate had a total of six aquaria, three containing early juveniles and the other three containing advanced juveniles groups. Each aquarium had an excess small PVC pipes that served as shelters. After 12 weeks, early juveniles raised in small stones or fine sand had a statistically significant heavier body mass than the control group while the advanced juveniles did not show statistically significant differences in body weight. In a second experiment, ten early and ten advanced juveniles were individually placed in a circular glass aquarium divided into four sections each containing one of the same substrates used in the first experiment. Each individual was filmed for 24 h, and the time spent in each compartment was registered. Both sizes of juveniles showed a marked preference for the small stones. This experiment was repeated with animals used in the first experiment and observed the same selection pattern indicating that substrate selection is independent of body mass or previous acclimation to the different substrates.Fil: Viau, Veronica Elizabeth. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Rodriguez, Enrique Marcelo. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
Morphology of the male reproductive system and spermatophore formation in the freshwater “red claw” crayfish Cherax quadricarinatus (Von Martens, 1898) (Decapoda, Parastacidae)
Get PDFThe morphology of the male reproductive system was studied in Cherax quadricarinatus. The testes and vasa deferentia were dissected, fixed, cut and stained. Testes appear as two parallel and opalescent strands; they present many testicular lobes, each lobe containing cells in the same stage of the spermatogenic cycle. A vas deferens arises from the external side of each testis and three parts were clearly distinguished: proximal vas deferens (PVD), middle vas deferens (MVD) and distal vas deferens (DVD). The PVD is opalescent and highly convoluted, the MVD is pale white in colour and convoluted, but wider in diameter than the PVD, while the DVD shows the widest diameter, is straight and is white in colour. A single-layered epithelium is recognized in the vas deferens; with cylindrical cells in the PVD and cuboid cells in the MVD and DVD. The formation of the spermatophore starts at the PVD, while the secondary layer of the spermatophore seems to be added at the MVD. At the DVD, the highly coiled spermatophore is surrounded by the periodic acid Schiff-positive sticky components of the secondary layer. Many aspects of spermatophore formation in C. quadricarinatus differ from those of other Astacida. The applied aspects of this study for aquaculture purposes are discussed.Fil: Lopez, Laura Susana. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Vazquez, Fernanda Jimena. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario; ArgentinaFil: Rodriguez, Enrique Marcelo. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario; Argentin
Systemic and lymphatic heart performance during forced submersion, in the toad Bufo arenarum (Annura, Bufonidae)
No full textLa actividad bioeléctrica del corazón sistémico (SH) y de los corazones linfáticos (LH) posteriores fue estudiada durante la sumersión forzada en el sapo Bufo arenarum. Previo a la sumersión, la frecuencia cardiaca fue de 28.9 latidos por minuto y la de los LH fue de 50.5 latidos por minuto, y asincrónica. Al comienzo de la sumersión forzada, inmediatamente después que las narinas están bajo la superficie del agua, se registra una detención refleja de la bomba bucal y una lenta y gradual disminución de la frecuencia cardiaca, estabilizándose en 10 latidos por minuto después de 15 min. A los 10 min de sumersión, los LH se detuvieron completamente. La emersión implica una breve fase sin bombeo bucal, seguida por una activación de dicha bomba junto con el repentino incremento de la frecuencia del SH y la reactivación de los LH. Animales vagotomizados bilateralmente mostraron una alta frecuencia cardiaca, comparada con los controles, y bradicardia durante la sumersión. Varios mecanismos, nerviosos y no nerviosos, tales como estímulos químicos sanguíneos, permitirían mantener la bradicardia sistémica y la inactividad de los LH durante el proceso de sumersión. Los resultados no permiten establecer una conclusión definitiva acerca de los mecanismos responsables de la bradicardia y en la detención de la actividad de los LH durante la sumersión, pero la correlación entre la actividad de la bomba bucal y el establecimiento de profundos cambios en la fisiología de ambos corazones, sugiere que la primera es un factor necesario para que se produzcan las modificacionesFil: Cervino, Claudio O.. Universidad de Morón; ArgentinaFil: Castillo, Lilian Fedra. Universidad de Morón; ArgentinaFil: Rodriguez, Enrique Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentin
Effects of glyphosate and polyoxyethylene amine on metabolic rate and energy reserves of Procambarus clarkii juveniles
Get PDFP. clarkii juvenile crayfish were exposed during 60 days to sublethal concentrations of glyphosate (G), polyoxyehtylene amine (P) or a combination of both (G+P), together with a control group of aged tap water (C). At the end of the experiment, the following statistical differences were noted, with respect to control: 1) a lower metabolic rate in both G and G+P groups, 2) a higher glycemia in G group with no differences in hemolymphatic lactate levels, 3) a lower muscle glycogen levels in both P and G+P groups, 4) a lower level of protein muscle in the P group. Taken together, these results suggest that glyphosate may cause a metabolic arrest. Additionally, under chronic exposure conditions, polyoxyehtylene amine acts as a strong stressor, leading to the utilization of both muscle carbohydrate and protein reserves.Fil: Frontera, Jimena Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; ArgentinaFil: Gilette, N.. Widener University; Estados UnidosFil: Hull, B.. Widener University; Estados UnidosFil: Korang, J.. Widener University; Estados UnidosFil: Amorin, C.. Widener University; Estados UnidosFil: Vatnick, I.. Widener University; Estados UnidosFil: Rodriguez, Enrique Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; Argentin
Efectos de ecdisona y de la aclimatación a baja temperatura, sobre el crecimiento y la tasa metabólica de juveniles de la langosta de agua dulce Cherax quadricarinatus (Decapoda, Parastacidae)
Get PDFGrowth, metabolic rate, and energy reserves of Cherax quadricarinatus (von Martens, 1868) juveniles were evaluated in crayfish acclimated for 16 weeks to either 25 ºC (temperature near optimum) or 20 ºC (marginal for the species). Additionally, the modulating effect of ecdsyone on acclimation was studied. After 12 weeks of exposure, weight gain of both experimental groups acclimated to 25 ºC (control: C25, and ecdysone treated: E25) was significantly higher than that of those groups acclimated to 20 ºC (C20 and E20). A total compensation in metabolic rate was seen after acclimation from 25 ºC to 20 ºC; for both the control group and the group treated with ecdysone. A Q10 value significantly higher was only observed in the group acclimated to 20 ºC and treated with ecdysone. A reduction of glycogen reserves in both hepatopancreas and muscle, as well as a lower protein content in muscle, was seen in both groups acclimated to 20 ºC. Correspondingly, glycemia was always higher in these groups. Increased lipid levels were seen in the hepatopancreas of animals acclimated to 20 ºC, while a higher lipid level was also observed in muscle at 20 ºC, but only in ecdysone-treated crayfish.RESUMEN. Efectos de ecdisona y de la aclimatación a baja temperatura, sobre el crecimiento y la tasa metabólica de juveniles de la langosta de agua dulce Cherax quadricarinatus (Decapoda, Parastacidae). Se evaluaron las reservas energéticas, el crecimiento y la tasa metabólica de langostas juveniles de agua dulce Cherax quadricarinatus (von Martens, 1868), aclimatadas durante 16 semanas tanto a 25°C (temperatura cercana al óptimo) como a 20°C (temperatura marginal para la especie). Adicionalmente, se evaluó el efecto modulador de la ecdisona sobre la aclimatación. Luego de 12 semanas de exposición, la ganancia en peso de ambos grupos experimentales aclimatados a 25°C (control: C25, y tratados con ecdisona: E25) fue significativamente mayor que la de los grupos aclimatados a 20°C (C20 and E20). Se verificó una compensación total en la tasa metabólica, luego de la aclimatación desde 25 a 20°C, tanto para el grupo control como para el tratado con ecdisona. Solamente se observó un valor de Q10 significativamente mayor en el grupo aclimatado a 20°C y tratado con ecdisona. En ambos grupos aclimatados a 20°C, se determinó un reducción en la reservas de glucógeno, tanto en hepatopancreas como en músculo, así como un
menor contenido de proteína en músculo. Correspondiente, la glucemia resultó siempre más elevada en esos grupos, que también mostraron un mayor nivel de lípidos en el hepatopancreas, siendo mayor el nivel de lípidos en músculo sólo para los juveniles aclimatados a 20°C y tratados con ecdisona.Fil: Chaulet, Anouk. Consejo Nacional de Invest.cientif.y Tecnicas. Oficina de Coordinacion Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biologia Experimental y Aplicada; Argentina;Fil: Vatnick, Itzick. Widener University Department of Biology; Estados Unidos de América;Fil: Rodriguez, Enrique Marcelo. Presidencia/directorio - Conicet. Gerencia de Des.cient.y Tec.. Oficina de Coordinacion Administrativa Cdad. Universitaria. Instituto de Biodiversidad y Biologia Experimental y Aplicada; Argentina
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