ABSTRACT
Shrimp trawling is considered a significant negative impact on the marine ecosystem, especially on the benthic community. Sea stars (Echinodermata: Asteroidea) are one of the most affected groups by unintentional catches. This study was performed at the Santana Archipelago, a Marine Protected Area in the northern region of Rio de Janeiro State, between 2008-2009. Sea stars accidentally caught by trawling were collected during open and closed season of the shrimp fisheries (Xiphopenaeus kroyeri) at depths of 5-60 m. A generalized linear zero-inflated model was applied to test for differences in capture between fishing seasons and depths. A total of 158 sea star specimens were captured. These specimens were identified as Asterina stellifera, Astropecten acutiradiatus, Astropecten brasiliensis, Astropecten cingulatus, Luidia alternata alternata, Luidia clathrata, Luidia ludwigi scotti, Luidia senegalensis. The sea stars A. brasiliensis and L. senegalensis are currently considered as vulnerable species in the Brazilian official list of threatened species. The higher capture of sea stars was shown in deepest areas, and there was no significant difference in the number of specimens between seasons. This is the first study about asteroids accidentally captured by shrimp trawling.(AU)
Subject(s)
Animals , Starfish , Ecosystem , Palaemonidae , Echinodermata , Fisheries , Endangered SpeciesABSTRACT
HIGHLIGHTS Fluoxetine increases the metabolic rate and excretion of ammonia in both species. O:N ratio in fish showed higher values in the highest concentrations of fluoxetine. The LC50 - 96 hour values of Palaemon pandaliformis represented greater toxicity. Both species are a good biological model for fluoxetine exposure studies.
Abstract Fluoxetine is an emerging pollutant that acts as a selective serotonin reuptake inhibitor (SSRI) and being a hydrolytic molecule that is photolytically stable and accumulaties in biological tissues, its disposal in the aquatic environment can interfere with the physiology of fish and shrimp. Thus, the objective of this study was to analyze the effects of fluoxetine on routine metabolism (metabolic rate, specific ammonia excretion and O:N ratio) of Deuterodon iguape and Palaemon pandaliformis. For this, five groups of each species, were exposed to different concentrations of fluoxetine for 24 hours (D. iguape) and 2 hours (P. pandaliformis). The results demonstrated that in D. iguape exposure to fluoxetine significantly increased both the metabolic rate by 75%, 85%, 55% and 50% for concentrations of 0.05; 0.1; 0.5 and 1.0 mgL-1, respectively, and the specific ammonia excretion by 40%, 48% and 20% for concentrations of 0.05; 0.1 and 0.5 mgL-1, respectively, when compared with their control. The O:N ratio was statistically greater in concentrations of 0.5 and 1.0 mgL-1. Concerning P. pandaliformis, exposure to fluoxetine increased metabolic rate at concentrations 30.0 and 60.0 µgL-1, and also increased specific ammonia excretion at concentrations 10.0, 30.0 and 60.0 µgL-1, when compared with the control group. It was concluded that exposure to fluoxetine increases the routine metabolism of both species and that at the concentration 1.0 mgL-1, Deuterodon iguape required different energy substrates.
Subject(s)
Fluoxetine/metabolism , Palaemonidae/drug effects , Ammonia/metabolism , Models, BiologicalABSTRACT
This study aimed to describe the Macrobrachium rosenbergii hepatopancreas histomorphology. The hepatopancreas is constituted by a set of blind end tubules, divided into proximal, middle, and distal regions, with the epithelium formed by E, F, B, R, and M cells differently of other species. Measurements of the length and width of the tubules were 419.64+69.09µm and 117.42+16.99µm, respectively. The percentage of each cell type per region was: proximal region (40%B, 20%F, 6.7%M, 33.3%R), middle region (45.4%B, 18.2%F, 9.1%M, and 27.3%R) and distal region (36.4%E, 27.2%B, 18.2%F, 9.1%M, 9.1%R). Cell B that stores glycogen and lipids, is the most commonly found cell in proximal and middle regions. In the distal region, the E, responsible for the mitosis, is the most prominent. M, responsible by nutrient storage, is numerically constant among the portions differently in the Macrobrachium amazonicum. The study for the first time also suggests that in addition to digestive enzymes, the F cell produces protective mucus. The present study generated for the first time a morphometric profile of M. rosenbergii hepatopancreas, demonstrating differences from other species, and can be an important tool for new studies in nutrition, reproduction, and production with the species.(AU)
O objetivo do presente estudo foi descrever a histomorfologia do hepatopâncreas do camarão-de-água-doce Macrobrachium rosenbergii. Observou-se que ele é constituído por um conjunto de túbulos de fundo cego, sendo cada túbulo dividido em regiões proximal, média e distal, com o epitélio formado por cinco tipos de células (E, F, B, R, M), diferentemente de outras espécies. As medidas de comprimento e largura dos túbulos foram de 419,64+69,09µm e 117,42+16,99µm, respectivamente. A porcentagem de cada tipo celular por região foi: região proximal (40%B, 20%F, 6,7%M, 33,3%R), região média (45,4%B, 18,2%F, 9,1%M e 27,3%R) e região distal (36,4%E, 27,2%B, 18,2%F, 9,1%M, 9,1%R). Assim, a B, que armazena glicogênio e lipídeos, é a célula mais encontrada nas regiões proximal e média. Na região distal, a célula E, responsável pela mitose, é a mais encontrada. A célula M, responsável pelo acúmulo de nutrientes, tem um número constante de células nas porções do túbulo, diferentemente do Macrobrachium amazonicum. O estudo também sugere, pela primeira vez, que a célula F produz, além de enzimas digestivas, um muco protetor para o túbulo hepatopancreático. O presente estudo foi o primeiro a gerar um perfil morfométrico do hepatopâncreas do M. rosenbergii e demonstrou diferenças em relação a outras espécies, bem como serviu de importante ferramenta para novos estudos que abranjam a produção, a nutrição e a reprodução para a espécie.(AU)
Subject(s)
Animals , Hepatopancreas , Palaemonidae/anatomy & histology , Digestive SystemABSTRACT
Abstract Macrobrachium surinamicum is a small shrimp that inhabits rivers of low salinity. It is mainly caught as bycatch in Amazon shrimp Macrobrachium amazonicum fisheries, which is widely exploited by artisanal fisheries for food and economic needs of the riverside population. This study aimed to characterize the spatial and temporal distribution of the freshwater shrimp M. surinamicum in the Guajará Bay and on Mosqueiro Island, correlating the abundance of this species with abiotic factors (temperature and salinity). Samples were taken from May 2006 to April 2007 in six locations: Mosqueiro Island (Furo das Marinhas and Porto do Pelé); Icoaraci district; Arapiranga Island, edge of the city of Belém; and Combu Island, using traps named 'matapis'. A total of 361 shrimps were caught. The abundance was higher in December and lower in July 2006. The biggest catch occurred on Arapiranga Island and the lowest on Mosqueiro Island. The abundance differed significantly in December 2006 and no variable studied had significant influence on M. surinamicum abundance. In Guajará Bay, particularly the more sheltered places, as Arapiranga and Combu islands, favor the development of M. surinamicum, indicating that this species has preference for less disturbed areas.
Resumo Macrobrachium surinamicum é um camarão de pequeno porte que habita a foz de rios e águas de baixa salinidade. Sua captura na Amazônia ocorre principalmente como fauna associada à pesca do camarão-da-Amazônia Macrobrachium amazonicum que é largamente explorado pela pesca artesanal atendendo as necessidades alimentícias e econômicas da comunidade ribeirinha. O presente estudo teve como objetivo caracterizar a distribuição espaço-temporal do camarão dulcícola M. surinamicum na Baía do Guajará e Ilha de Mosqueiro, correlacionando a abundância desta espécie com fatores abióticos (temperatura e salinidade). Os exemplares foram capturados no período de maio/06 a abril/07 em seis locais: Ilha de Mosqueiro (Furo das Marinhas e Porto do Pelé), Distrito de Icoaraci, Ilha do Arapiranga, orla de Belém e Ilha do Combu com armadilhas (matapis). Um total de 361 camarões foi capturado, sendo a maior abundância em dezembro e a menor em julho de 2006. A maior captura foi na Ilha de Arapiranga e a menor na Ilha de Mosqueiro. A abundância diferiu significativamente em dezembro/06 e nenhuma variável estudada teve influência significativa na abundância de M. surinamicum. A Baía do Guajará, especialmente os locais mais abrigados como a Ilha de Arapiranga e do Combu, propiciam o desenvolvimento de M. surinamicum, o que indica que esta espécie tenha preferência para áreas menos antropizadas.
Subject(s)
Animals , Male , Female , Palaemonidae/physiology , Animal Distribution , Temperature , Brazil , Population Density , Estuaries , Palaemonidae/growth & development , SalinityABSTRACT
AbstractEcologists have been largely interested in the description and understanding of the power scaling relationships between body size and abundance of organisms. Many studies have focused on estimating the exponents of these functions across taxonomic groups and spatial scales, to draw inferences about the processes underlying this pattern. The exponents of these functions usually approximate -3/4 at geographical scales, but they deviate from this value when smaller spatial extensions are considered. This has led to propose that body size-abundance relationships at small spatial scales may reflect the impact of environmental changes. This study tests this hypothesis by examining body size spectra of benthic shrimps (Decapoda: Caridea) and snails (Gastropoda) in the Tamiahua lagoon, a brackish body water located in the Eastern coast of Mexico. We measured water quality parameters (dissolved oxygen, salinity, pH, water temperature, sediment organic matter and chemical oxygen demand) and sampled benthic macrofauna during three different climatic conditions of the year (cold, dry and rainy season). Given the small size of most individuals in the benthic macrofaunal samples, we used body volume, instead of weight, to estimate their body size. Body size-abundance relationships of both taxonomic groups were described by tabulating data from each season into base-2 logarithmic body size bins. In both taxonomic groups, observed frequencies per body size class in each season were standardized to yield densities (i.e., individuals/m3). Nonlinear regression analyses were separately performed for each taxonomic group at each season to assess whether body size spectra followed power scaling functions. Additionally, for each taxonomic group, multiple regression analyses were used to determine whether these relationships varied among seasons. Our results indicated that, while body size-abundance relationships in both taxonomic groups followed power functions, the parameters defining the shape of these relationships varied among seasons. These variations in the parameters of the body size-abundance relationships seems to be related to changes in the abundance of individuals within the different body size classes, which seems to follow the seasonal changes that occur in the environmental conditions of the lagoon. Thus, we propose that these body size-abundance relationships are influenced by the frequency and intensity of environmental changes affecting this ecosystem. Rev. Biol. Trop. 64 (1): 33-44. Epub 2016 March 01.
ResumenLos ecólogos han estado muy interesados en describir y comprender las relaciones escalares de potencia entre el tamaño corporal y la abundancia de los organismos. Muchos estudios se han centrado en la estimación de los exponentes de estas funciones a través de grupos taxonómicos y escalas espaciales, para sacar conclusiones acerca de los procesos que subyacen a este patrón. Los exponentes de estas funciones generalmente se aproximan -3/4 a escalas geográficas, pero se apartan de este valor cuando se consideran extensiones espaciales más pequeñas. Esto ha llevado a proponer que las relaciones tamaño corporal-abundancia en pequeñas escalas espaciales puede reflejar el impacto de cambios ambientales. Este estudio pone a prueba esta hipótesis mediante el examen de los espectros de tamaño corporal de camarones bentónicos (Decapoda: Caridea) y caracoles (Gastropoda) en la laguna de Tamiahua, un cuerpo de agua salobre situado en la costa oriental de México. Medimos parámetros de calidad del agua (oxígeno disuelto, salinidad, pH, temperatura del agua, materia orgánica en los sedimentos y demanda química de oxígeno) y muestreamos la macrofauna bentónica en tres momentos del año que difieren en sus condiciones climáticas (estaciones fría, seca y de lluvias). Dado el pequeño tamaño de la mayoría de los individuos en las muestras de macrofauna bentónica, se utilizó el volumen del cuerpo, en lugar de peso, para estimar su tamaño corporal. Las relaciones tamaño corporalabundancia de ambos grupos taxonómicos fueron descritas ordenando los datos de cada estación en clases de tamaño corporal cuya amplitud estaba establecida por una escala logarítmica de base 2. En ambos grupos taxonómicos, las frecuencias observadas por clase de tamaño corporal en cada estación se estandarizaron a densidades de captura (es decir, individuos/m3). Análisis de regresión no-lineal se realizaron separadamente para cada grupo taxonómico en cada estación del año para evaluar si los espectros de tamaño corporal seguían funciones escalares de potencia. Además, para cada grupo taxonómico, se utilizaron análisis de regresión múltiple para determinar si estas relaciones variaban entre estaciones. Nuestros resultados indicaron que, mientras las relaciones tamaño corporal-abundancia en ambos grupos taxonómicos siguieron funciones potenciales, los parámetros que definen la forma de estas relaciones variaron entre estaciones. Estas variaciones en los parámetros de las relaciones tamaño corporal-abundancia parecen estar relacionadas con cambios en la abundancia de los individuos dentro de las diferentes clases de tamaño corporal, que parece seguir los cambios estacionales que se producen en las condiciones ambientales de la laguna. Por lo tanto, proponemos que estas relaciones tamaño corporalabundancia se ven influidas por la frecuencia e intensidad de los cambios ambientales que afectan este ecosistema.
Subject(s)
Animals , Snails/anatomy & histology , Snails/classification , Water Quality , Palaemonidae/anatomy & histology , Palaemonidae/classification , Body Size , Seasons , MexicoABSTRACT
Current research analyzed the behavioral activities of Macrobrachium rosenbergii and its preference for colored shelters in male monosex, female monosex and mixed culture. Ten shrimps m-2 were maintained in eight 250-L aquaria. Three artificial shelters, colored red, black and orange, were placed in each aquarium. Four aquaria were maintained in light/dark photoperiod respectively between 6h00 am and 6h00 pm and between 6h00 pm and 6h00 am, whereas the other four aquaria were submitted to an inverted photoperiod. The animals were observed for 30 days by Focal Animal Method for 15 minutes, with instantaneous recording every 60 seconds, at six different instances within the light and dark phases. Preference for black shelters occurred in male monosex and mixed cultures, whereas red and orange shelters were the preference of female monosex. M. rosenbergii kept in the shelter mostly during the light phase in male monosex and mixed populations. Results suggest that black, red and orange shelters may improve the animals' well-being in the culture since aggressive encounters would decrease, especially during the light phase.
Esta pesquisa analisou as atividades comportamentais de Macrobrachium rosenbergii e a preferência pela coloração de abrigos em cultivos monosexo macho, monosexo femea e mistos. Dez camarões m-2 foram mantidos em oito aquários de 250 L. Três abrigos artificiais (vermelho, preto e laranja) foram disponibilizados em cada aquário. Quatro aquários foram submetidos à fase clara de 6h00 18h00 e à fase escura das 18h00 6h00, e quatro submetidos a fotoperíodo invertido. Os animais foram observados usando Método Animal Focal por 15 minutos, com registro instantâneo a cada 60 segundos, em seis diferentes momentos na fase clara e na fase escura, por 30 dias de observação. Nos cultivos monosexo macho e misto ocorreu uma forte preferência por abrigos de cor preta. No cultivo monosexo fêmea, os camarões preferiram abrigos vermelhos e laranja. M. rosenbergii entoca-se mais frequentemente na fase clara, em populacões monosexo macho e mistas. Estes resultados sugerem que a colocação de abrigos nas cores preto, vermelho e laranja, poderão contribuir com a melhoria do bem-estar dos animais em cultivo, uma vez que podem reduzir a ocorrência de encontros agressivos, principalmente na fase clara do dia.
Subject(s)
Ethology , Palaemonidae , ShelterABSTRACT
Probably as a function of their wide geographical distribution, the different population of Macrobrachium amazonicum shrimp may present distinct physiological, biochemical, reproductive, behavioral, and ecological patterns. These differences are so accentuated that the existence of allopatric speciation has been suggested, although initial studies indicate that the genetic variability of populations happen at an intraspecific level. Among the biological responses described for M. amazonicum populations, those regarding osmoregulation and metabolism play a key role for being related to the occupation of diverse habitats. To this effect, we investigated osmoregulation through the role of free amino acids in cell volume control and metabolism, through oxygen consumption in larvae (zoeae I, II, V and IX) and/or post-larvae of a M. amazonicum population from Amazon, kept in aquaculture fish hatcheries in the state of São Paulo. The results add information regarding the existence of distinct physiological responses among M. amazonicum populations and suggest that possible adjustments to metabolism and to the use of free amino acids as osmolytes of the regulation of the larvae and post-larvae cell volume depend on the appearance of structures responsible for hemolymph osmoregulation like, for example, the gills. In this respect, we verified that zoeae I do not alter their metabolism due to the exposition to fresh or brackish water, but they reduce intracellular concentration of free amino acids when exposed to fresh water, what may suggest the inexistence or inefficient performance of the structures responsible for volume regulation and hemolymph composition. On the other hand, in zoeae II and V exposed to fresh and brackish water, metabolism alterations were not followed by changes in free amino acids concentration. Thus it is possible, as the structures responsible for osmoregulation and ionic regulation become functional, that the role of free amino acids gets diminished and oxygen consumption elevated, probably due to greater energy expenditure with the active transportation of salts through epithelial membranes. Osmotic challenges also seem to alter throughout development, given that in zoeae II oxygen consumption is elevated on brackish water of 18, but in zoeae V it happens in fresh water. After M. amazonicum metamorphosis, free amino acids begin to play an important role as intracellular osmolytes, because we verified an increase of up to 40% in post-larvae exposed to brackish water of 18. The main free amino acids involved in cell volume regulation of ontogenetic stages evaluated were the non essential ones: glutamic acid, glycine, alanine, arginine, and proline. Interestingly, larvae from estuarine population studied here survived until the zoeae V stage in fresh water, but in some populations far from the sea, zoeae die right after eclosion in fresh water or they do not reach zoeae III stage. In addition, given that in favorable conditions caridean shrimp larvae shorten their development, we may infer that the cultivation environment, in which larvae developed in the present work, was appropriate, because almost all zoeae VIII kept on brackish water underwent metamorphosis directly to post-larvae and did not go through zoeae IX stage.
Provavelmente como função da sua ampla distribuição geográfica, as diferentes populações do camarão Macrobrachium amazonicum podem apresentar distintos padrões fisiológicos, bioquímicos, reprodutivos, comportamentais e ecológicos. Essas diferenças são tão acentuadas que tem sido sugerido a existência de especiação alopátrica embora estudos iniciais indiquem que a variabilidade genética das populações ocorre ao nível intraespecífico. Dentre as respostas biológicas descritas para as populações de M. amazonicum, aquelas relacionadas à osmorregulação e metabolismo têm papel central por estarem relacionadas à ocupação dos diversos habitats. Nesse sentido, investigou-se a osmorregulação, por meio do papel dos aminoácidos livres no controle do volume celular e o metabolismo, por meio do consumo de oxigênio, em larvas (zoeas I, II, V e IX) e/ou pós-larvas de uma população de M. amazonicum oriunda da Amazônia e mantida em viveiros de aquicultura no estado de São Paulo. Os resultados adicionam informações a respeito da existência de respostas fisiológicas distintas entre as populações de M. amazonicum e sugerem que possíveis ajustes no metabolismo e no uso de aminoácidos livres como osmólitos da regulação do volume celular das larvas e pós-larvas dependem do surgimento de estruturas responsáveis pela osmorregulação da hemolinfa como, por exemplo, as brânquias. Nesse sentido, verificou-se que as zoeas I não alteram seu metabolismo em função da exposição à água doce ou salobra, mas reduzem a concentração intracelular de aminoácidos livres quando expostas à água doce, o que pode sugerir a inexistência ou um desempenho ineficiente das estruturas responsáveis pela regulação do volume e composição da hemolinfa. Por outro lado, nas zoeas II e V expostas à água doce ou salobra alterações no metabolismo não foram acompanhadas por mudanças na concentração dos aminoácidos livres. Assim é possível que à medida que estruturas responsáveis pela osmo e ionorregulação tornam-se funcionais, o papel dos aminoácidos livres se torne reduzido e o consumo de oxigênio elevado, provavelmente em função do maior gasto energético com o transporte ativo de sais através das membranas epiteliais. Os desafios osmóticos também parecem se alterar ao longo do desenvolvimento visto que em zoeas II o consumo de oxigênio é elevado em água salobra de 18 mas em zoeas V essa resposta ocorre em água doce. Após a metamorfose de M. amazonicum, os aminoácidos livres passam a ter papel importante como osmólitos intracelulares, pois se verificou um aumento de até 40% nas pós-larvas expostas à água salobra de 18. Os principais aminoácidos livres envolvidos na regulação do volume celular dos estágios ontogenéticos avaliados foram os não essenciais ácido glutâmico, glicina, alanina, arginina e prolina. Interessantemente, as larvas da população estuarina aqui estudada sobrevivem até o estágio de zoea V em água doce mas em algumas populações distantes do mar as zoeas morrem logo após a eclosão em água doce ou não chegam ao estágio de zoea III. Adicionalmente, visto que em condições favoráveis as larvas de camarões carídeos abreviam o seu desenvolvimento pode ser inferido que o meio de cultivo em que as larvas se desenvolveram no presente trabalho foi adequado, pois quase todas as zoeas VIII mantidas em água salobra sofreram diretamente a metamorfose para pós-larvas e não passaram pelo estágio de zoeas IX.
Subject(s)
Animals , Adaptation, Physiological/physiology , Fresh Water , Larva/metabolism , Osmoregulation/physiology , Palaemonidae/metabolism , Salinity , Larva/growth & development , Larva/physiology , Palaemonidae/growth & development , Palaemonidae/physiologyABSTRACT
The aim of this study was to assess the feasibility of integrated multi-trophic culture of Nile tilapia (Oreochromis niloticus) and Amazon River prawn (Macrobrachium amazonicum) in brackish water by evaluating its limnological characteristics and economic performance. The experiment was completely randomized with four treatments and four repetitions: control treatment with Nile tilapia only, stocked with 2 tilapias/m² (P2C0) and three integrated multi-trophic culture treatments stocked with 2 tilapias/m² and prawns at densities of 4, 8 and 16 prawns/m² (P2C04, P2C08 and P2C16, respectively). The limnological variables of temperature, pH, dissolved oxygen, turbidity, ammonia, orthophosphate and chlorophyll "a" were evaluated and throughout the experiment remained within the limits recommended for culture. The experiment lasted 150 days with monthly animal sampling. No significant differences were observed for total fish biomass or for fish and prawn total survival rates. However, prawn individual weight decreased as stocking density increased. Gross revenue was not significantly different between treatments, as well as profitability. The profitability was 40.1% (P2C0), 36.7% (P2C04), 41.2% (P2C08) and 50.1% (P2C16). It is concluded that although feasible from the view point of husbandry, the integrated multi-tropic culture of M. amazonicum and O. niloticus did not influence significantly profitability compared to the monoculture system.
O objetivo deste estudo foi verificar a viabilidade do cultivo multitrófico integrado da tilápia-do-nilo (Oreochromis niloticus) e do camarão-da-amazônia (Macrobrachium amazonicum) em água salobra, mediante a avaliação de suas características limnológicas e de seu desempenho econômico. O experimento foi inteiramente ao acaso, com quatro tratamentos e quatro repetições: tratamento controle somente com tilápia-do-nilo, estocado com duas tilápias/m² (P2C0) e três tratamentos de cultivo multitrófico integrado, estocados com duas tilapias/m² e camarões nas densidades de quatro, oito e 16 camarões/m² (P2C04, P2C08 e P2C16, respectivamente). As variáveis limnológicas temperatura, pH, oxigênio dissolvido, turbidez, amônia, ortofosfato e clorofila "a" foram avaliadas e, durante todo o experimento, mantiveram-se dentro dos limites recomendados para o cultivo. O experimento durou 150 dias, com amostragem mensal dos animais. Diferenças significativas não foram observadas para a biomassa total de peixe nem para a taxa de sobrevivência total em peixes e camarões. Entretanto, o peso individual do camarão diminuiu à medida que a densidade de estocagem aumentou. A receita bruta não foi significativamente diferente entre os tratamentos, assim como a rentabilidade. A rentabilidade foi 40,1% (P2C0), 36,7% (P2C04), 41,2% (P2C08) e 50,1% (P2C16). Conclui-se que, apesar de viável do ponto de vista da larvicultura, o cultivo multitrófico integrado de M. amazonicum e O. niloticus não influenciou significativamente a rentabilidade quando comparado com o sistema de monocultura.
Subject(s)
Animals , Aquaculture/methods , Aquaculture/standards , Cichlids/growth & development , Palaemonidae/growth & developmentABSTRACT
In recent years, the use of new scientific techniques has effectively improved aquaculture production processes. Astaxanthin has various properties in aquacultureand its antioxidant benefits have been closely related to stress resistance; besides, it is an essential factor for growth in many crustaceans and fish. The objective of this study was to evaluate the resistance of prawn (Macrobrachium nipponense) fed diets containing different amounts of astaxanthin (AX) to the shock and stress of differentphysicochemical environments. A 70-day trial was conducted to evaluate the effect of supplementation of a source of astaxanthin (Carophyll Pink, 10% astaxanthin, w/w, Hoffman-La Roche, Switzerland) at various levels in the diet of M. nipponense juveniles. Four dry diets were prepared: AX0 without astaxanthin, AX50 with 50mg/kg, AX100 with 100mg/kg, and AX150 with 150mg/kg astaxanthin. The feeding trial was conducted in a recirculation water system consisting of 12 fiberglass tanks (1 000L) used for holding prawns. Three replicate aquaria were initially stocked with 36org/m² per tank. During the trial, prawns were maintained on a 12:12-h light:dark photoperiod with an ordinary incandescent lamp, and the water quality parameters were maintained as follows: water temperature, 25-26°C; salinity, 1g/L; pH, 8.5-8.8; dissolved oxygen, 6.0-6.5mg/L; and ammonia-nitrogen, 0.05mg/L. Incorporation of AX, production output, and physiological condition were recorded after 10 weeks of feeding. At the end of the growing period, the prawns were exposed to thermal shock (0°C), ammonia (0.75mg/L), and reduced oxygen (0.5mg/L). The time to lethargyand the time to complete death of the prawns were recorded. The results showed that control prawns had the shortest time to lethargy and death compared with prawns subjected to the other treatments. The results of this study have shown that the amount of muscle tissue and gill carotenoids in prawn fed with an AX150 diet showed greater reduction than those exposed to other treatments. It is possible that higher levels of astaxanthin in the body under oxygen reduction stress can be beneficial forprawns. These results suggest that male prawns showed lethargy earlier than females, and the percentage of carotenoid reduction in muscle and gill tissues was higher inmales. Rev. Biol. Trop. 62 (4): 1331-1341. Epub 2014 December 01.
En años recientes, la utilización de nuevas técnicas científicas ha tenido un efecto importante en mejorar los procesos de producción en acuicultura. La astaxantina tiene varias propiedades en la acuicultura y sus propiedades antioxidantes se encuentran estrechamente relacionadas con la resistencia al estrés. La astaxantina en muchos crustáceos y peces es un factor esencial para el crecimiento. El objetivo de este estudio fue evaluar la resistencia del langostino (Macrobrachium nipponense) alimentado con dietas conteniendo diferentes cantidades de astaxantina (AX), bajo diferentes condiciones de estrés ambiental. Un ensayo de 70 días fue llevado a cabo para evaluar el efecto de la suplementación de fuentes de astaxantina (Carophyll Pink, 10 % astaxanthin) en varios niveles en la dieta de jóvenes de M. nipponense. Cuatro dietas fueron preparadas: AX0 sin astaxantina, AX50 con 50mg/kg, AX100 con 100mg/kg y AX150 con 150mg/kg de astaxantina. Los ensayos de alimentación fueron conducidos en un sistema de recirculación de agua consistente en 12 estanques de fibra de vidrio (1 000L). Tres replicas fueron sembradas con 36org/m2 por tanque. Durante el experimento los langostinos fueron mantenidos con un fotoperiodo de 12:12 luz:oscuridad con lámparas incandescentes y los parámetros de la calidad del agua fueron mantenidos a 25-26°C la temperatura, 1 g/L la salinidad, 8.5-8.8 el pH, 6.0-6.5 mg/L el oxígeno y 0.05mg/L el nitrógeno amoniacal. La incorporación de la astaxantina, producción y condiciones fisicoquímicas fueron registradas después de 10 semanas de alimentación. Al final del periodo de crecimiento, los langostinos fueron expuestos a un shock térmico (0°C), amonio (0.75mg/L) y reducción de oxígeno 0.5 mg/L. El tiempo de letargia y el tiempo de muerte fueron registrados. Se encontró que la dieta con la mayor concentración de astaxantina (150mg/kg) presentó el mayor tiempo de letargia y la mayor concentración en branquias y músculo en el langostino M. nipponense.
Subject(s)
Animals , Female , Male , Animal Feed , Ammonia/pharmacology , Dietary Supplements , Palaemonidae/drug effects , Aquaculture , Heat-Shock Response/drug effects , Palaemonidae/physiology , Survival Analysis , Time Factors , Xanthophylls/administration & dosageABSTRACT
The efficiency of a series of wetland colonized with Eichhornia crassipes and Salvinia molesta to treat the effluent of a giant river prawn (Macrobrachium rosenbergii) broodstock pond was evaluated in this study. The experimental design was completely randomized and was performed in 9 rectangular tanks (1.6 m3) with three treatments (constructed wetlands) and three replicates. The treatment types included: a wetland colonized with E. crassipes and S. molesta (EcSm) arranged sequentially, a wetland with E. crassipes only (Ec) and a wetland with S. molesta only (Sm). The means of suspended particulate material (SPM), total inorganic nitrogen (TIN), total Kjeldahl nitrogen (TKN), P-orthophosphate (PO4-P) and total phosphorus (TP) of the treated effluents were compared using ANOVA followed by Tukey's test (P<0.05). The effluent treated in Ec and EcSm wetlands exhibited lower SPM concentrations. The Ec wetland reduced TIN, TKN, PO4-P and TP by 46.0, 43.7, 44.4 and 43.6%, respectively. In the EcSm wetland, the reduction of TIN (23.0%), TKN (33.7%) and PO4-P (26.7%) was similar to the Sm wetland (19.8% TIN, 30.9% TKN and 23.8% PO4-P). The Ec wetland was more efficient in treating pond effluent due likely to the higher root surface of E. crassipes, which forms an extensive area favorable to retention and adsorption of debris and absorption of nutrients.
Neste estudo foi avaliada a eficiência de uma wetland povoada com Eichhornia crassipes e Salvinia molesta para o tratamento do efluente de um viveiro de manutenção de reprodutores do camarão-da-malásia (Macrobrachium rosenbergii). Um experimento totalmente casualizado foi realizado em 9 tanques retangulares (1,6 m3) com 3 tratamentos (wetlands construídas) e 3 repetições. Os tratamentos foram: wetland povoada com E. crassipes e S. molesta (EcSm) dispostas nesta sequência, wetland somente com E. crassipes (Ec) e wetland somente com S. molesta (Sm). Os valores de material particulado em suspensão (MPS), nitrogênio inorgânico total (NIT), nitrogênio Kjeldahl total (NKT), P-ortofosfato (P-PO4) e fósforo total (PT) dos efluentes tratados foram comparados pela ANOVA seguida do teste de Tukey (P<0,05). A wetland Ec reduziu a concentração de NIT, NKT, P-PO4 e PT em 46,0%, 43,7%, 44,4% e 43,6%. Na wetland EcSm a redução de NIT (23,0%), NKT (33,7%) e P-PO4 (26,7%) foi semelhante à observada na wetland Sm (19,8% para NIT, 30,9% para NKT e 23,8% para P-PO4). A wetland povoada com E. crassipes é mais eficiente no tratamento do efluente do viveiro, provavelmente devido a maior superfície radicular da macrófita que permite a formação de uma extensa área propícia à retenção e adsorção dos detritos e à absorção dos nutrientes.
Subject(s)
Animals , Nitrogen/analysis , Palaemonidae/physiology , Phosphorus/analysis , Wetlands , Aquaculture , Eichhornia , Palaemonidae/classificationABSTRACT
This study records, for the first time, the occurrence of all four male morphotypes in a population of Macrobrachium amazonicum from a continental environment, with an entirely freshwater life cycle. The specimens studied came from the Tietê River, state of São Paulo, Brazil, and were collected in a lotic environment downstream from Ibitinga Dam. This population was compared with other continental populations, including a population from the dam itself, collected in a previous study. Four samples of 30 minutes were taken monthly, using a trap, from January to April 2011. Each male specimen was measured with respect to seven body dimensions as follows: carapace length (CL), right cheliped length (RCL), dactyl length (DCL), propodus length (PPL), carpus length (CRL), merus length (ML) and ischium length (IL). The relative growth was analyzed based on the change in growth patterns of certain body parts in relation to the independent variable CL. The four male morphotypes proposed for the species were found using morphological and morphometric analyses. Different biological characteristics were found between the populations studied. The male population of the lake of Ibitinga and from Pantanal presented mean sizes and number of morphotypes lower than the population studied here. These differences seem to be closely related to ecological characteristics of the environments inhabited by these populations. Our results supported the hypothesis that coastal and continental populations of M. amazonicum belong to the same species.
Este estudo registra, pela primeira vez, a ocorrência dos quatro morfotipos de Macrobrachium amazonicum em uma população continental com ciclo de vida totalmente dulcícola. Os camarões são provenientes do Rio Tietê, estado de São Paulo, Brasil, e foram coletados em um ambiente lótico abaixo da Barragem de Ibitinga. Essa população foi comparada com outras populações provenientes de ambientes continentais, incluindo a de um estudo anterior na represa da barragem de Ibitinga. Quatro amostras de 30 minutos foram realizadas mensalmente, utilizando armadilhas, de janeiro a abril de 2011. Cada indivíduo macho foi mensurado em relação a sete dimensões corporais, sendo elas: comprimento da carapaça (CL), comprimento total do quelípodo direito (RCL), comprimento do dáctilo (DCL), comprimento do própodo (PPL), comprimento do carpo (CRL), comprimento do mero (ML) e comprimento do ísquio (IL). O crescimento relativo foi analisado de acordo com as mudanças nas taxas de crescimento de determinadas partes do corpo em relação à variável independente CL. Os quatro morfotipos descritos para a espécie foram encontrados, utilizando análises morfológicas e morfométricas. Diferentes características biológicas foram encontradas entre a população estudada e as demais, incluindo a proveniente do reservatório. A população de machos da represa de Ibitinga e do Pantanal apresentaram tamanhos médios e número de morfotipos inferiores aos da população estudada aqui. Essas diferenças parecem estar intimamente relacionadas às características ecológicas dos ambientes onde estas populações estão inseridas. A hipótese de que populações costeiras e continentais de M. amazonicum pertençam à mesma espécie é suportada por nossos resultados.
Subject(s)
Animals , Female , Male , Palaemonidae/anatomy & histology , Palaemonidae/classification , Brazil , Fresh Water , Life Cycle Stages/physiology , Palaemonidae/physiology , Reproduction/physiologyABSTRACT
El trabajo tuvo como objetivo evaluar la actividad antibacteriana in vitro de soluciones ácidas de quitosano obtenido a partir del exoesqueleto de camarón, sobre siete bacterias patógenas, cinco de las cuales corresponden a patógenas de humanos (Enterococcus faecalis ATCC 29212, Escherichia coli UDS, Pseudomonas aeruginosa ATCC 27853, Klebsiella oxytoca ATCC 43863 y K. oxytoca ATCC 43086) y las fitopatógenas (Pectobacterium sp UDS y Burkholderia glumae 320012-CIAT). Concentraciones de soluciones de quitosano de 1.0, 1.5, 2.0, 2.5, 3.0 y 3.5 % (v/v) disuelto en ácido acético de 1.0, 1.5, 2.0 % (v/v) fueron preparadas; a partir de estas concentraciones, mediante la técnica de Kirby-Bauer se evaluó la actividad antibacteriana in vitro. Los resultados de actividad antimicrobiana mostraron diferencias altamente significativas entre la especie de bacteria y los tratamientos de quitosano. Las bacterias P. aeruginosa, E. coli, K. oxytoca (ATCC 43086 y ATCC 43863) fueron las más susceptibles a los tratamientos, mientras que E. faecalis, Pectobacterium sp y B. glumae mostraron resistencia. Los tratamientos T3, T4, T5, T7, T8, T9 en donde las concentraciones de quitosano estuvieron por encima a las del ácido acético, se presentaron mayores valores medios de actividad de antimicrobiana en mm y aumentó este valor para los tratamientos T9 (5.8095 mm), T8 (6.00 mm) para y T9 (5.8095 mm), donde las concentraciones de quitosano de 2.5 y 3.5%, disuelta en ácido acético fueron igual a 2%. Los resultados de este estudio en el Caribe Colombiano permitirán a futuro el reaprovechamiento del exoesqueleto de camarón como fuente de quitosano como un compuesto potencial frente al manejo al problema de salud pública ocasionada por las enfermedades bacterianas.
The work was to evaluate the in vitro antibacterial activity of chitosan obtained from exoskeleton of shrimp, on seven pathogenic bacteria, five of which corresponded to human pathogenic strain (ATCC 29212 Enterococcus faecalis, Escherichia coli UDS, Pseudomonas aeruginosa ATCC 27853, Klebsiella oxytoca, K. oxytoca ATCC 43863 and ATCC 43086) and two phytopathogenic strain (Pectobacterium sp UDS and Burkholderia glumae 320012-CIAT). Solution of chitosan of 1.0, 1.5, 2.0, 2.5, 3.0 and 3.5% (v/v) dissolved in 1.0, 1.5, 2.0% (v / v) acetic acid was prepared and from these is by diffusion through the Kirby-Bauer technique was evaluated for antibacterial activity in vitro. The results of the antimicrobial activity showed significant differences between the species of bacteria and chitosan treatments evaluated. P. aeruginosa, E. coli and K. oxytoca (ATCC 43086 and ATCC 43863) were the most susceptible to the treatments, while E. faecalis, B. glumae and Pectobacterium sp were resistant. The treatments T3, T4, T5, T7, T8, T9, where chitosan concentrations were above the acetic acid, showed higher mean mm antimicrobial activity and this value increased to T9 treatments (5.8095 mm ), T8 (6.00 mm) and T9 (5.8095 mm), where chitosan concentrations 2.5 and 3.5% solution in acetic acid was equal to 2%. The results of this study in the Colombian Caribbean enable future reuse of the exoskeleton of shrimp as a source of chitosan as a potential compound against handling the public health problem caused by bacterial diseases.
Subject(s)
Animal Shells , Chitosan , Artemia , Decapoda , Host-Pathogen Interactions , PalaemonidaeABSTRACT
Objective. Evaluate the effects of varying dietary protein and lipid levels on the growth and body composition of adult freshwater prawns, Macrobrachium carcinus (Linnaeus 1758), in a recirculation system for 11 weeks (77 days). Materials and methods. The experimental treatments were assigned in triplicate. Six test diets were formulated with three different protein levels (35, 40 and 45%) and two lipid levels (8 and 13%). Results. The highest survival rate, growth indices and feed utilization were observed for M. carcinus adults fed protein:lipid diets of 35:13, 40:13 and 45:13, and the lowest values for these parameters were recorded for prawns fed diets with the lowest lipid levels; the differences in these parameters between these types of diets were significant (p<0.05). A non-significant tendency for an increased percentage of protein in the body with an increased dietary protein level was observed. The percentage of lipids decreased with an increasing dietary protein level, and no definite trends in ash content were found. Conclusions. The results suggest that a diet with 35% dietary crude protein and 13% lipids enhances the growth and body composition of adult M. carcinus.
Objetivo. Evaluar los efectos de diversos niveles dietéticos de proteína y lípidos en el crecimiento y composición corporal de reproductores del langostino de agua dulce Macrobrachium carcinus (Linnaeus 1758), en un sistema de recirculación durante 11 semanas (77 días). Materiales y métodos. Los tratamientos experimentales fueron asignados por triplicado. Seis dietas de prueba fueron formuladas con tres niveles diferentes de proteínas (35, 40 y 45%) y dos niveles de lípidos (8 y 13%). Resultados. Se observó la tasa más alta de supervivencia, índices de crecimiento y utilización del alimento para ejemplares adultos de M. carcinus alimentados con niveles dietarios de proteína: lípidos de 35:13, 40:13 y 45:13, mientras que el valor más bajo en estos parámetros se registró en langostinos alimentados con el nivel más bajo de lípidos; las diferencias en estos parámetros entre estos tipos de dietas fueron significativas (p<0.05). Se observó una tendencia no significativa en un aumento del porcentaje de proteína en el cuerpo con un nivel mayor de proteína dietética. El porcentaje de lípidos disminuyó con un nivel de proteína dietario creciente, y no se encontró ninguna tendencia definida en el contenido de cenizas. Conclusiones. Los resultados sugieren que una combinación de dieta de proteína cruda del 35% y 13% de lípidos mejora el crecimiento y composición corporal de M. carcinus adultos.
Subject(s)
Diet , Growth , Nutritional Sciences , PalaemonidaeABSTRACT
BACKGROUND: Acute toxicity testing were carried out the freshwater swamp shrimp, Macrobrachium nipponense, as the model animal for the semiconductor applied metals (gallium, antimony, indium, cadmium, and copper) to evaluate if the species is an suitable experimental animal of pollution in aquatic ecosystem. RESULTS: The static renewal test method of acute lethal concentrations determination was used, and water temperature was maintained at 24.0 ± 0.5°C. Data of individual metal obtained from acute toxicity tests were determined using probit analysis method. The median lethal concentration (96-h LC50) of gallium, antimony, indium, cadmium, and copper for M. nipponense were estimated as 2.7742, 1.9626, 6.8938, 0.0539, and 0.0313 mg/L, respectively. CONCLUSIONS: Comparing the toxicity tolerance of M. nipponense with other species which exposed to these metals, it is obviously that the M. nipponense is more sensitive than that of various other aquatic animals.
Subject(s)
Animals , Antimony/toxicity , Cadmium/toxicity , Copper/toxicity , Gallium/toxicity , Indium/toxicity , Palaemonidae/drug effects , Ecosystem , Fresh Water , Toxicity Tests, Acute , Water Pollution , Water QualityABSTRACT
White coloration of the muscle of the giant river prawn (Macrobrachium rosenbergii) is a serious problem in China. The Macrobrachium rosenbergii Nodavirus (MrNV) has been confirmed to be the pathogen that causes this disorder. To develop a rapid, sensitive and specific technology for the detection of Macrobrachium rosenbergii Nodavirus isolated from China (MrNV-China), a reverse-transcription loop- mediated isothermal amplification assay combined with a lateral flow dipstick (RT-LAMP-LFD) assay method is described. A set of four primers and a labeled probe were designed specifically to recognize six distinct regions of the MrNV RNA2 gene. Results showed the sensitivity of the RT-LAMP-LFD assay was ten-times higher than the reverse-transcription loop-mediated isothermal amplification assay (RT-LAMP) with agarose gel electrophoresis. The assay was conducted with one-step amplification at 61°C in a single tube within 45 min. No product was generated from shrimps infected with other viruses, including DNA viruses (infectious hypodermal and hematopoietic necrosis virus (IHHNV); white spot syndrome virus (WSSV)) and RNA viruses (Taura syndrome virus (TSV); infectious myonecrosis virus (IMNV); yellow head virus (YHV)). Results were visualized by the LFD method. Therefore, the described rapid and sensitive assay is potentially useful for MrNV detection.
Subject(s)
Animals , Nodaviridae , Nucleic Acid Amplification Techniques , Methods , Palaemonidae , Virology , Reverse TranscriptionABSTRACT
A invasão da água doce por crustáceos ocorreu repetidamente ao longo dos anos, pressionando um ajuste em seus processos fisiológicos. A habilidade de sobreviver aos diferentes ambientes foi encontrada em traços osmorregulatórios, e estão relacionadas à capacidade de regular o fluido extracelular. Portanto, o objetivo deste manuscrito é explorar os processos osmorregulatórios de camarões palemonídeos e peneídeos, visualizando um padrão na capacidade osmorregulatória em ambas as famílias e, em particular, tratar de assuntos pertinentes aos efeito no ciclo ontogenético e o efeito ocasionado pelo nitrito na hemolinfa de crustáceos. Comparando palemonídeos e peneídeos, percebe-se que o sucesso da conquista do ambiente dulcícola, e a não necessidade de hiporregulação, levou à perda dessa capacidade na maioria dos palemonídeos. Dessa forma, se supõem um ancestral com capacidade hiporregulatória, uma vez que invertebrados marinhos são, parcimoniosamente, osmoconformadores. Compara-se também que o nitrito apresenta efeito nas proteínas presentes na hemolinfa dos crustáceos quando submetidos à exposição natural ou induzida deste composto, e que a capacidade osmorregulatória é, portanto, variada de acordo com seus estágios...
The invasion of freshwater by crustaceans has occurred repeatedly over the years, pressing for an adjustment in their physiological processes. The ability to survive in different environments was found in osmoregulatory traits and is related to the ability to regulate the extracellular fluid. Therefore, the purpose of this manuscript is to explore the osmoregulatory processes in palaemonid and penaeid shrimps, which display a pattern of osmoregulatory capacity in both families and, in particular, to deal with matters related to the effects on ontogenetic cycle and the effect raised by nitrite in crustacean hemolymph. By comparing palaemonid and peneid shrimps, it is possible to note the success of conquering freshwater environment, and not the need for hypo-regulation, has led to the loss of this capability in most palaemonids. Thus, it is assumed that they share an ancestor with hypo-regulatory capacity, since marine invertebrates are sparsely osmoconformers. The article also compares that nitrite has effect on proteins present in the hemolymph of crustaceans when subjected to natural or induced exposure to these compound, and osmoregulatory capacity is therefore varied according to their stages...
La invasión del agua dulce por crustáceos ocurre repetidamente a lo largo de los años, pulsando un ajuste en sus procesos fisiológicos. La capacidad de sobrevivir en diferentes ambientes se ha encontrado en rasgos osmorregulatorios y están relacionados a la capacidad de regular el fluido extracelular. Por lo tanto, el objetivo de este manuscrito es el de explotar los procesos osmorregulatorios de camarones palemonídeos y peneídeos, se muestra un estándar en la capacidad osmorregulatoria en ambas las familias y, en especial, trata de cuestiones relativas a los efectos sobre los ciclo ontogenético y el efecto causado por nitrito en la hemolinfa de crustáceos. Comparando palemonídeos y peneídeos, se da cuenta de que el éxito de la conquista del ambiente dulcícola, y sin necesidad de hipo regulación, condujo a la pérdida de esa capacidad en la mayoría de los palemonídeos. Así, se supone un ancestral con capacidad hipo regulatoria, una vez que los invertebrados marinos son, parsimoniosamente, osmoconformadores. Se compara también que el nitrito presenta efectos en las proteínas presentes en la hemolinfa de los crustáceos cuando sometidos a la exposición natural o inducida por estes compuesto, y que la capacidad osmorregulatoria es, por lo tanto, variada de acuerdo con sus etapas...
Subject(s)
Animals , Decapoda/growth & development , Decapoda/physiology , Palaemonidae/genetics , Penaeidae/genetics , ToxicologyABSTRACT
The aim of this study was to describe the population structure and reproduction of Macrobrachium jelskii from a stream in the central region of São Paulo State. A total of 1,215 specimens was collected monthly during one year (February 2008 to January 2009), being 535 males, 578 females and 102 juveniles. The overall sex-ratio was not significantly different from the expected 1:1, but has significantly differed in some months. A total of 136 ovigerous females were collected and the reproductive period was continuous with peak of occurrence on the hottest months. An increase in juveniles following the highest frequency of ovigerous females was observed and characterized the recruitment period. The fecundity was low and varied from 1 to 56 eggs per female. The biological profile observed here matched, in general aspects, with the pattern developed by tropical and subtropical inland populations, with some particularities related with environmental characteristics.
O objetivo deste estudo foi descrever a estrutura populacional e a reprodução de Macrobrachium jelskii de um ribeirão na região central do Estado de São Paulo. Um total de 1215 espécimes foi coletado mensalmente durante o período de um ano (fevereiro de 2008 a janeiro de 2009), sendo 535 machos, 578 fêmeas e 102 juvenis. A razão sexual total não foi significantemente diferente da esperada 1:1, mas diferiu significativamente em alguns dos meses coletados. Um total de 136 fêmeas ovígeras foi coletado e o período reprodutivo foi considerado contínuo com pico de ocorrência nos meses mais quentes. Um aumento no número de juvenis foi identificado após a mais alta frequência de fêmeas ovígeras e caracterizou o período de recrutamento. A fecundidade foi baixa e variou de 1 a 56 ovos por fêmea. O perfil biológico observado aqui correspondeu, em aspectos gerais, com o padrão desenvolvido por populações continentais tropicais e subtropicais, com algumas particularidades relacionadas com as características do ambiente.
Subject(s)
Crustacea , Decapoda , Fertility , Palaemonidae , ReproductionABSTRACT
The palaemonid shrimp Macrobrachium amazonicum shows an unusually large geographic range (ca. 4 000km across) living in coastal, estuarine, and limnic inland habitats of the upper Amazon, Orinoco, and La Plata basins. This raises doubts whether allopatric, ecologically diverse populations belong to the same species. While shrimps from estuarine and Amazonian habitats have been studied in great detail, very little is known about hololimnetic inland populations. In the present study, biological traits related to growth (maximum body size, fresh weight, morphometric relationships) and reproduction (sex ratio; occurrence of male morphotypes; minimum sexable size; minimum size of ovigerous females; fecundity; egg size), were studied in M. amazonicum collected from a pond culture and two natural freshwater habitats (Rio Miranda; Lagoa Baiazinha) in the Pantanal of Mato Grosso do Sul, Brazil. In total, 2 270 shrimps were examined (603 males; 1 667 females, 157 of these ovigerous). Sex ratio (males:females) was at all sampling sites strongly female-biased, ranging from 0.2-0.6. Maximum body size was larger in natural habitats compared to the pond culture, suggesting reduced growth or a shorter life span under artificial mass rearing conditions. Maximum fecundity observed in our material was 676 eggs, reached by the largest female (TL=65mm; Lagoa Baiazinha). A significant difference between slope parameters of linear regressions describing fecundity, either in terms of numbers of eggs laid or of larvae released, in relation to female fresh weight, indicates egg losses. This may be due in part to a 2.4-fold increase in egg volume occurring during the course of embryonic development, while the available space under the abdomen remains limited. Size-weight relationships differed significantly between males and females, indicating sexspecific morphometric differences. Males appear to have a more slender body shape than females, reaching thus lower weight at equal TL. When reproductive and morphometric traits are compared with literature data from estuarine and inland populations living in the Amazon and Orinoco plains, shrimps from the Pantanal show conspicuous peculiarities differing from other populations: (1) maximum body size is far smaller, suggesting shorter longevity; (2) females are consistently larger than males; (3) different male morphotypes are absent; (4) minimum sexable size and (5) minimum size of ovigerous females are smaller. These traits suggest a heterochronic shift (predisplacement) of sexual maturation and r-selection. In summary, our data show biologically relevant differences in life-history traits of shrimps from the Pantanal compared to M. amazonicum populations in other regions. All these differences persist also in long-term cultures maintained under constant conditions. Altogether, our data support the hypothesis that M. amazonicum in the Paraná-Paraguay drainage basin has phylogenetically diverged from allopatric populations that are hydrologically separated by continental watersheds, implying an at least incipient vicariant speciation.
El camarón palaemónido Macrobrachium amazonicum muestra una distribución geográfica inusualmente grande (aprox. 4 000km de diámetro), vive en las zonas costeras, estuarios y hábitats interiores límnicos del alto Amazonas, Orinoco y las cuencas de La Plata. Esto plantea dudas sobre sí poblaciones alopátricas y ecológicamente diversas pertenecen a la misma especie. Mientras que los camarones de estuarios y de hábitats Amazónicos se han estudiado con gran detalle, se sabe muy poco acerca de las poblaciones holo-limnéticas del interior. En el presente estudio, los rasgos biológicos relacionados con el crecimiento (tamaño máximo del cuerpo, peso fresco, relaciones morfométricas) y la reproducción (proporción de sexos; ocurrencia de morfotipos masculinos; tamaño mínimo sexable; tamaño mínimo de las hembras ovígeras; fecundidad; tamaño del huevo), fueron estudiados en M. amazonicum recolectados en un estanque de cultivo y dos hábitats naturales de agua dulce (Río Miranda; Baiazinha Lagoa) en el Pantanal de Mato Grosso do Sul, Brasil. En total, 2 270 camarones fueron examinados (603 machos, 1 667 hembras, 157 de estas ovígeras). La proporción de sexos (machos:hembras) fue en todos los sitios de muestreo fuertemente sesgada por hembras, desde 0.2 hasta 0.6. El tamaño corporal máximo fue mayor en los hábitats naturales comparado con el estanque de cultivo, sugeriendo un crecimiento reducido o un lapso de vida más corto en condiciones artificiales de crianza masiva. La fecundidad máxima observada en nuestro material fue 676 huevos, alcanzado por la hembra de mayor tamaño (largo total, LT=65mm). Una diferencia significativa entre los parámetros de pendiente de regresiones lineales que describen la fecundidad, comparando el número de huevos puestos o de larvas liberadas, en relación con el peso de la hembra, indican pérdida de huevos. Esto puede ser debido a un aumento de 2.4 veces en el volumen del huevo que ocurre durante el desarrollo embrionario, mientras que el espacio disponible bajo el abdomen sigue siendo limitado. Relaciones de tamaño-peso diferían significativamente entre machos y hembras, lo que indica diferencias morfométricas sexoespecíficas. Los machos parecen tener una forma de cuerpo más delgado que las hembras, alcanzando por lo tanto el peso más bajo en la igualdad de LT. Cuando los rasgos reproductivos y morfométricos son comparados con datos de la literatura de poblaciones estuarinas y poblaciones del interior que viven en el Amazonas y en los llanos del Orinoco, los camarones del Pantanal muestran peculiaridades diferentes: (1) el tamaño máximo del cuerpo es mucho más pequeño, lo que sugiere menor longevidad; (2) las hembras son más grandes que los machos; (3) diferentes morfotipos masculinos están ausentes; (4) el tamaño mínimo sexable y (5) el tamaño mínimo de hembras ovígeras son más pequeños. Estas características sugieren un cambio heterocrónico (pre-desplazamiento) de la maduración sexual y la selección-r. En resumen, nuestros datos muestran diferencias biológicamente relevantes en los rasgos de la historia de vida de los camarones del Pantanal comparados con M. amazonicum en otras regiones. Todas estas diferencias persisten también en cultivos a largo plazo mantenidos bajo condiciones constantes. En conjunto, nuestros datos apoyan la hipótesis que M. amazonicum en la desembocadura de la cuenca Paraná-Paraguay ha divergido filogenéticamente de poblaciones alopátricas que están hidrológicamente separadas por cuencas continentales, lo que implica al menos una incipiente especiación vicariante.
Subject(s)
Animals , Female , Male , Palaemonidae/physiology , Body Size , Brazil , Fertility/physiology , Oviposition/physiology , Palaemonidae/anatomy & histology , Palaemonidae/growth & development , Reproduction/physiology , Sex RatioABSTRACT
Se determinó la presencia de Giardia intestinalis y Cryptospodidium parvum, bacteriófagos de Escherichia coli y organismos indicadores de contaminación (OIC), en muestras de camarones para el consumo humano comercializados en el estado Zulia. Los parásitos se concentraron a partir de sistemas digestivos de pools de camarones por la técnica de formol-éter y se cuantificaron por inmunofluorescencia directa. La concentración de los bacteriófagos de E. coli F+ y los OIC se evaluó por técnicas estándar. En este trabajo se detectó la presencia de G. intestinalis, C. parvum, bacteriófagos y E. coli en camarones comercializados en el estado Zulia que cumplían los criterios de la normativa venezolana de calidad sanitaria e inocuidad. Del total de muestras analizadas el 91,5% fueron positivas para G. intestinalis (promedio: 36,6 quistes/100g), 95,3% para C. parvum (promedio: 32,8 ooquistes/100g), 100% para los bacteriófagos de E coli F+ (promedio de 2,8 x 103 UFP/100 g) y 71,5% para E. coli (promedio de 4,3 x 104 NMP/g). Los resultados obtenidos indican que los camarones pueden convertirse en un vehículo para la transmisión de patógenos al hombre y dejan en evidencia la necesidad de la inclusión de un parámetro parasitológico y viral en el control de la calidad microbiológica de estos productos alimenticios.
The presence of G. intestinalis and C. parvum, E. coli F+ bacteriophages and fecal pollution indicator organisms was determined in shrimp for human consumption marketed in the State of Zulia. Parasites were concentrated from the digestive systems of shrimp pools, detected by formalin-ether and quantified by direct immunofluorescence. E. coli F + bacteriophage and pollution indicator organism concentrations were determined by standard techniques. In this work, G. intestinalis, C. parvum, E. coli F + bacteriophages and E. coli were detected in shrimp for human consumption marketed in the State of Zulia that met the quality criteria of Venezuelan health and safety regulations. 91.5% of the samples analyzed were positive for G. intestinalis (average: 36.6 cyst/100g), 95.3% for C parvum (average: 32.8 oocyst/100g), 100% for E coli F + bacteriophages (average: 2.8 x 103 FPFU/100g) and 71.5% for E. coli (average: 4.3 x 104 MPN/g). Results of this research indicate that shrimp can become a vehicle for transmitting pathogens to humans and demonstrate the need for including a parasitic and viral parameter in microbiological quality control for seafood.
Subject(s)
Animals , Bacteriophages/pathogenicity , Food Contamination/analysis , Giardia lamblia/parasitology , Palaemonidae/microbiology , Palaemonidae/parasitology , Pandalidae/microbiology , Pandalidae/parasitology , Penaeidae/microbiology , Penaeidae/parasitology , Seafood/analysis , Commerce , Pollution Indicators/analysis , Pollution Indicators/methodsABSTRACT
Objetivo.Evaluar el efecto de cinco niveles de proteína cruda (PC) en alimentos balanceados sobre el crecimiento, sobrevivencia y tasa de conversión alimenticia (FCA) en juveniles de Macrobrachium tenellum. Materiales y métodos. Se alimentó por 60 días a juveniles de M. tenellum (0.31±0.01 g y 32.62±1.10 mm) con niveles de 20, 25, 30, 35 y 40% de PC en el alimento. Los organismos fueron distribuidos al azar en 15 tinas experimentales de 64 L (15 org./tina) bajo condiciones controladas (5.95±0.41 ppm de oxígeno, 29.89±0.72°C, y pH 8.44±0.15) y alimentados con el 10% de su peso vivo. Resultados. El porcentaje de sobrevivencia fue del 98.22±3.96% sin diferencias significativas entre los tratamientos (p>0.05). Los organismos alimentados con un 40% de PC tuvieron un peso significativamente mayor (p<0.05) respecto a los demás tratamientos (cambio de peso de 0.54±0.02g; incremento de peso de 173.60±12.99%; y tasa de crecimiento específico de 1.68±0.08). El FCA fue significativamente mejor (p<0.05) en los organismos alimentados con 35 y 40% de PC (2.85±0.18 y 2.40±0.05, respectivamente) que los demás tratamientos. Conclusiones. Los organismos juveniles de M. tenellum alimentados con niveles altos de proteína (40%), se desarrollaron más rápido que organismos que recibieron una menor concentración de proteína bajo las condiciones experimentales establecidas en este estudio.
Objective. To evaluate the effect of five levels of crude protein (CP) in balanced feed on the survival, growth and feed conversion ratio (FCA) in juveniles of Macrobrachium tenellum. Materials and methods. Juveniles of M. tenellum (0.31±0.01g and 32.62±1.10mm) were fed for 60 days with 20, 25, 30, 35 and 40% of CP in feed. The organisms were randomly distributed in 15 experimental tanks (15 org /tank) under controlled conditions (5.95±0.41 ppm of oxygen, 29.89 ± 0.72 °C, and pH 8.44±0.15) and fed with 10% of its live weight. Results. The survival percentage was 98.22±3.96% with no statistical difference between treatments (p>0.05). The organisms fed with 40% CP in their diet had a significantly higher weight (p<0.05) compared to the other treatments (weight change of 0.54±0.02g; weight increase 173.60±12.99%, and specific growth rate of 1.68±0.08). The FCA was significantly better (p<0.05) in organisms fed with 35 and 40% CP (2.85±0.18 and 2.40±0.05, respectively) than other treatments. Conclusions. Juveniles of M. tenellum fed with high protein levels (40%) developed faster than organisms which received a lower concentration of the protein under the experimental conditions established for this study.