Vibrio spp. from Macrobrachium amazonicum prawn farming are inhibited by Moringa oleifera extracts

OBJECTIVE@#To investigate the in vitro antimicrobial potential of extracts of stem, leaves, flowers, pods and seeds of Moringa oleifera (M. oleifera) against Vibrio spp. from hatchery water and the prawn Macrobrachium amazonicum.@*METHODS@#The ethanol extracts of stem, leaves, pods and seeds and chloroform extract of flowers of M. oleifera were tested against Vibrio cholerae (V. cholerae) serogroups non-O1/non-O139 (n = 4), Vibrio vulnificus (n = 1) and Vibrio mimicus (n = 1). Escherichia coli (E. coli) (ATCC(®) 25922) was used as quality control. Vibrio species were obtained from Macrobrachium amazonicum prawns and from hatchery water from prawn farming. The Minimum Inhibitory Concentration (MIC) was determined by broth microdilution method.@*RESULTS@#The best result was obtained with the ethanol extract of pods, which inhibited three strains of the V. cholerae, Vibrio vulnificus, Vibrio mimicus and E. coli (MIC range 0.312-5.000 mg/mL). The chloroform extract of flowers was effective against all V. cholerae strains and E. coli (MIC range 0.625-1.250 mg/mL). However, the ethanol extracts of stem and seeds showed low effectiveness in inhibiting the bacterial growth.@*CONCLUSIONS@#The extracts of pods, flowers and leaves of M. oleifera have potential for the control of Vibrio spp. Further studies are necessary to isolate the bioactive compounds responsible for this antimicrobial activity.

Vibrio spp. from Macrobrachium amazonicum prawn farming are inhibited by Moringa oleifera extracts

Objective: To investigate the in vitro antimicrobial potential of extracts of stem, leaves, flowers, pods and seeds of Moringa oleifera (M. oleifera) against Vibrio spp. from hatchery water and the prawn Macrobrachium amazonicum. Methods: The ethanol extracts of stem, leaves, pods and seeds and chloroform extract of flowers of M. oleifera were tested against Vibrio cholerae (V. cholerae) serogroups non-O1/non-O139 (n = 4), Vibrio vulnificus (n = 1) and Vibrio mimicus (n = 1). Escherichia coli (E. coli) (ATCC® 25922) was used as quality control. Vibrio species were obtained from Macrobrachium amazonicum prawns and from hatchery water from prawn farming. The Minimum Inhibitory Concentration (MIC) was determined by broth microdilution method. Results: The best result was obtained with the ethanol extract of pods, which inhibited three strains of the V. cholerae, Vibrio vulnificus, Vibrio mimicus and E. coli (MIC range 0.312-5.000 mg/mL). The chloroform extract of flowers was effective against all V. cholerae strains and E. coli (MIC range 0.625-1.250 mg/mL). However, the ethanol extracts of stem and seeds showed low effectiveness in inhibiting the bacterial growth. Conclusions: The extracts of pods, flowers and leaves of M. oleifera have potential for the control of Vibrio spp. Further studies are necessary to isolate the bioactive compounds responsible for this antimicrobial activity.

Macrobrachium amazonicum: an alternative for microbiological monitoring of aquatic environments in Brazil / Macrobrachium amazonicum uma alternativa para o monitoramento microbiológico de ambientes aquáticos no Brasil

This study aimed to evaluate the role of the Amazon River prawn, Macrobrachium amazonicum, as carrier of Candida spp., by analyzing the correlation between Candida spp. from these prawns and their environment (surface water and sediment), through M13-PCR fingerprinting and RAPD-PCR. For this purpose, 27 strains of Candida spp. were evaluated. These strains were recovered from the gastrointestinal tract of adult M. amazonicum (7/27) from Catú Lake, Ceará State, Brazil and from the aquatic environment (surface water and sediment) of this lake (20/27). Molecular comparison between the strains from prawns and the aquatic environment was conducted by M13-PCR fingerprinting and RAPD-PCR, utilizing the primers M13 and OPQ16, respectively. The molecular analysis revealed similarities between the band patterns of eight Candida isolates with the primer M13 and 11 isolates with the primer OPQ16, indicating that the same strains are present in the digestive tract of M. amazonicum and in the aquatic environment where these prawns inhabit. Therefore, these prawns can be used as sentinels for environmental monitoring through the recovery of Candida spp. from the aquatic environment in their gastrointestinal tract.

Este estudo teve como objetivo avaliar o papel do camarão Macrobrachium amazonicum como carreador de Candida spp. do ambiente aquático, por meio da análise da correlação entre Candida spp. isoladas desse camarão e do seu ambiente (água de superfície e sedimento) através das técnicas de M13-PCR fingerprinting e RAPD-PCR. Para tanto, 27 cepas de Candida spp. foram avaliadas. Essas cepas foram recuperadas a partir do trato gastrointestinal de M. amazonicum adultos (7/27), oriundos da lagoa do Catú, Ceará, Brasil, e do meio aquático (águas superficiais e sedimentos) desse lago (20/27). A comparação molecular entre as cepas de camarões e o ambiente aquático foi conduzida por M13-PCR fingerprinting e RAPD-PCR, utilizando os iniciadores M13 e OPQ16, respectivamente. A análise molecular revelou semelhanças entre os padrões de bandas de oito isolados de Candida com o iniciador M13 e 11 isolados com o primer OPQ16, indicando que elas estão presentes no trato digestivo de M. amazonicum e no ambiente aquático, onde esses camarões habitam. Portanto, essa espécie de camarão pode ser usada como sentinela para monitoramento ambiental através da recuperação de Candida spp. do ambiente aquático, a partir do seu trato gastrointestinal.

Temporal variation in the water quality of ponds and effluent of grow-out ponds of Amazon River prawn Macrobrachium amazonicum

This study was conducted in the Crustacean Sector of the Aquaculture Center (CAUNESP) at the São Paulo State University, Jaboticabal (21°1522”S and 48°1848”W) São Paulo, Brazil, from December 2003 to May 2004. The aim was to examine the water quality parameters of importance to freshwater prawn culture, operated in a semi-intensive system in Amazon River. Nine 0.01-ha earthen ponds were stocked with 20 juveniles.m-2. Prawns were fed commercial diet at a rate of 7 to 9% of biomass until the 14th week. After 145 days of stocking, all ponds were drained and harvested. The following water parameters were determined weekly: dissolved oxygen, oxygen biochemical demand, pH, total alkalinity, electrical conductivity, suspended total solids and turbidity, N-nitrate, N-nitrite, N-nitrogen ammonia, N- total, soluble ortophosphate, total phosphorus, chlorophyll and pheophytin. In the semi-intensive culture system of M. amazonicum, there was no clear pattern of temporal variation in the limnological variables studied. Dissolved oxygen, pH, BOD, ammonia nitrogen and nitrate increased in the afternoon period while, the other variables did not change. In general, water quality is more dependent on the biological processes that occur in the pond than on the characteristics of the renewal water for some variable

Este estudio se llevó a cabo en el Sector de Crustáceos del Centro de Acuicultura (CAUNESP) de la Universidad Estadual Paulista, Jaboticabal (21°15'22”S y 48°18'48”W) en São Paulo, Brasil; entre diciembre de 2003 y mayo de 2004. El objetivo fue evaluar los parámetros de calidad de agua con importancia para los cultivos de camarón de agua dulce, operado en un sistema semi-intensivo de estanques en río Amazonas. Nueve estanques de 0,01 ha, fueron sembrados a una densidad de 20 juveniles.m-2, y alimentados con una dieta comercial a una tasa de 7 a 9% de la biomassa, hasta la semana 14. Después de 145 días de crianza, todos los estanques fueron drenados y cosechados. Se determinaron semanalmente los siguientes: oxígeno disuelto, demanda bioquímica de oxígeno, pH, alcalinidad total, conductividad eléctrica, sólidos totales en suspensión y turbidez, nitrato-N, N-nitrito, amoníaco-nitrógeno N, N-total, ortofosfato soluble, total fósforo, clorofila y feofitina. En el sistema de cultivo semi-intensivo de M. amazonicum, no hubo un patrón claro de variación temporal en las variables limnológicas estudiadas. Oxígeno disuelto, pH, DBO, nitrógeno amoniacal y nitratos aumentaron durante las tardes, mientras que las otras variables no cambiaron. En general, la calidad del agua es más dependiente de los procesos biológicos que se producen en el estanque, que de las características de la renovación del agua para alguna variable

Respostas comportamentais do camarão de água doce Macrobrachium amazonicum à estimulação por cloreto de amônia / Behavioural responses of the freshwater prawn Macrobrachium amazonicum to chemical with ammonium chloride

O objetivo do presente estudo foi analisar as respostas comportamentais do camarão de água doce Macrobrachium amazonicum, mediante estimulação química com cloreto de amônia a 100mM. Espécimes desse crustáceo foram posicionados em um aquário com quatro litros de água doce desclorificada, e um pulso de solução estimulante foi injetado no recipiente na extremidade oposta em relação à posição do animal. Os animais estudados não apresentaram resposta aos estímulos utilizados. Isso pode sugerir que o limiar de resposta comportamental é maior do que o limiar fisiológico dos neurônios receptivos primários, ou que o cloreto de amônia precisa ser associado com outros compostos ou determinadas variáveis físicas para poder gerar uma resposta ecológica na espécie estudada.

The objective of the present study was to analyze the behavioral responses of the freshwater prawn Macrobrachium amazonicum, elicited by stimulation with ammonium chloride at 100mM. Specimens were positioned in a four liter dechlorinated freshwater tank and a 0.5ml pulse of stimulant was applied in the opposing corner of the recipient. The studied animals demonstrated no response to the stimuli applied. This may suggest that the behavioral response threshold is higher than the physiological response threshold of the primary chemoreceptor neurons or that the ammonium chloride must be associated with other compounds or certain physical attributes in order to evoke an ethological reaction from the studied species.

Histoarchitectural features of the hepatopancreas of the Amazon River prawn Macrobrachium amazonicum / Histoarquitectura del hepatopáncreas del camarón de la Amazonia Macrobrachium amazonicum

In decapod crustaceans, the digestive gland is concerned with the digestion, absorption of nutrients, the storage of reserves and excretion. The metabolism and the histological and histochemical changes of the hepatopancreas are observed in response to physiological demands as moult, reproduction, digestive process. Thus the hepatopancreas structure should be recognized to provide important morphological information to future studies involving the nutrition requirements of freshwater prawn culture. In this study, second-generation Macrobrachium amazonicum produced from wild broodstock collected in the state of Para in Brazil were used. Thirty adult male and female M. amazonicum were selected and randomly transferred to five experimental units for macroscopic and microscopic studies. The hepatopancreas of M. amazonicum is a large, yellowish-brown, compact organ, which occupies much of the cephalothoracic cavity. It has right and left halves that are enclosed together in a laminar connective tissue capsule, and at the same time they are separated by an interstitial connective tissue. The two halves are thereby called the right and left hepatopancreatic lobes. The principal tubule gives rise to four secondary tubules at each hepatopancreatic lobe. The morphological and functional unit consists of a blind-ended hepatopancreatic tubule, considered in the present study as the hepatopancreatic lobule. Each hepatopancreatic tubule can be subdivided into distal, medial and proximal zones. The hepatopancreatic tubule is lined by a pseudostratified epithelium that consists of five different cell types, which include the E-cell (embryonic), F-cell (fibrillar), B-cell (blister-like), R-cell (resorptive) and M-cell (midgut or basal). It is important to emphasize that the function of each cell type in the hepatopancreas during the digestive cycle is not yet established for decapods.

La glándula digestiva en los crustáceos decápodos asume las funciones de digestión, absorción de nutrientes, almacenamiento de las reservas energéticas y excreción de metabolitos. El metabolismo y las alteraciones histológicas e histoquímicas son observados como respuesta a necesidades fisiológicas, tales como: muda, reproducción y procesos digestivos. Por lo tanto, se requiere conocer la estructura histológica del hepatopancreas con el fin de reunir información morfológica para futuros estudios que consideren las necesidades nutricionales para el cultivo de los camarones de agua dulce. Fueran utilizados 30 animales, machos y hembras de Macrobrachium amazonicum, producidos a partir de reproductores colectados en el Estado de Para, Brasil. Las observaciones macro y microscópicas permitieron concluir que el hepatopancreas del M. amazonicum es un órgano grande y compacto de color amarillo tendiendo a marrón, que ocupa la mayor parte de la cavidad céfalo-torácica. El órgano presenta dos mitades, derecha y izquierda, las cuales están envueltas por una cápsula de tejido conjuntivo, y al mismo tiempo, separadas por tejido conectivo intersticial. Las dos mitades del órgano son identificadas como lobos derecho e izquierdo. Cada lobo presenta un túbulo principal que origina cuatro túbulos secundarios. Por lo tanto, la unidad morfofuncional del hepatopancreas consiste en un túbulo hepatopancreático de fondo ciego, considerado en esta investigación como lóbulo hepatopancreático. Cada lóbulo hepatopancreático puede ser dividido en 3 regiones: distal, media y proximal, y en su totalidad, se observa revestido por epitelio seudo estratificado que reúne cinco tipos celulares: célula E (embrionaria), célula F (fibrilar), célula B (globosa), célula R (reabsortiva) y célula M (basal). Es importante enfatizar que la función de cada tipo celular del hepatopancreas no está todavía aclarada para los decápodos.

Reproductive cycle of Macrobrachium amazonicum females (Crustacea, Palaemonidae)

Macrobrachium amazonicum is considered a favorite Brazilian species of freshwater prawn for cultivation as a result of its quick development and because it is easy to maintain in captivity. The aim of this work is to describe the sexual cycle stages and determine maturation age of the female M. amazonicum, which was collected monthly from June, 2002 to May, 2003 in the Jaguaribe River, Itaiçaba, Ceará. A monthly sample of water was also collected to determine the following parameters: temperature, dissolved oxygen, pH and salinity. A monthly sample of females was selected among the individuals caught, to determine the total weight (W T), carapace length (L C) and abdomen+telson length (L A+T) and to register the number of non-ovigerous females (NOF) and ovigerous females (OF). Determining ovarian maturation stages of M. amazonicum was done in a laboratory by observing macroscopic characters such as coloring, size, location and appearance of ovarians examined by transparent carapace. The first maturation age was determined from the relative frequency of the total length (L T) of young and adult females. The environmental parameters of the Jaguaribe River did not hold any influence in the number of individuals collected. A total of 1,337 prawns were sampled, 513 males (38.4 percent) and 824 females (61.6 percent). The proportion between males and females in the studied population was of 1:1.6. Among the collected females, 492 (50.7 percent) did not carry eggs in their abdomens (NOF) and 332 (40.3 percent) carried eggs in their abdomens (OF). There was no record of intact females. Non-ovigerous females with mature ovaries were recorded throughout all the months of collection. The female ovaries were classified as immature (IM), rudimentary (RU), intermediary (IN) and mature (M). M. amazonicum females reach their first sexual maturity between 4.5 and 5.5 cm of total length.

Das espécies de camarão de água doce brasileiras, Macrobrachium amazonicum é a preferida para cultivo, devido ao seu rápido desenvolvimento e fácil manutenção em cativeiro. Este trabalho teve como objetivos caracterizar as fases do ciclo sexual e determinar a idade da primeira maturação de fêmeas de M. amazonicum, coletadas mensalmente, de junho de 2002 a maio de 2003, no Rio Jaguaribe, Itaiçaba, Ceará. Uma amostra de água do local foi coletada mensalmente para determinação dos seguintes parâmetros: temperatura, oxigênio dissolvido, pH e salinidade. Do total de indivíduos capturados mensalmente, uma amostra de fêmeas foi selecionada para determinação do peso total (W T), do comprimento do cefalotórax (L C) e do abdômen+telson (L A+T), e para registro de fêmeas não ovígeras (FNO) e ovígeras (FO). A determinação macroscópica dos estágios de maturação ovariana de M. amazonicum foi realizada pela observação da coloração, do tamanho, da posição e da aparência dos ovários observados por transparência da carapaça. A idade da primeira maturação foi determinada a partir da freqüência relativa de comprimento total (L T) de fêmeas jovens e adultas. Os parâmetros ambientais do Rio Jaguaribe não influenciaram no número de indivíduos coletados. Foram amostrados um total de 1.337 camarões, sendo 513 machos (38,4 por cento) e 824 fêmeas (61,6 por cento). A proporção entre machos e fêmeas na população foi de 1:1,6. Entre as fêmeas coletadas, 492 (50,7 por cento) não carregavam ovos no abdômen e 332 (40,3 por cento) carregavam ovos no abdômen. Não foram observadas fêmeas intactas. Foram registradas fêmeas não ovígeras com ovários maduros durante todo o período de coleta. Os ovários das fêmeas foram classificados como: imaturo (IM), rudimentar (RU), intermediário (IN) e maduro (M). Fêmeas de M. amazonicum atingem a primeira maturação sexual com comprimento total variando entre 4,5 e 5,5 cm.

Fecundity and fertility of Macrobrachium amazonicum (Crustacea, Palaemonidae)

In Brazil, studies with native freshwater prawn species were discontinued due to great importance of Macrobrachium rosenbergii. Therefore, it is necessary to continue investigations about our species, in order to develop technology adequate to our reality and in a future allow prawn farmers to culture other species. The aim of this study was to determine the fecundity and fertility of Macrobrachium amazonicum captured monthly from June 1999 to June 2001 from Jaguaribe River, Itaiçaba, Ceará, Brazil. Prawns were collected using fishing net and transferred at Biological Science Laboratory, Ceará State University (Fortaleza, Ceará, Brazil). Among the ovigerous M. amazonicum females, 60 were randomly selected to determine fecundity. The eggs adhered to the pleopods were taken out and they were then placed in a Gilson solution, and then stored in alcohol 70%. Individual fecundity was determined from the total egg counting, using a stereoscopic microscope. To determine fertility, ovigerous M. amazonicum females were stored in individual 10 L-glass tanks maintained under strong aeration. After the hatching, the larvae were siphoned and counted. The data referring to total length and weight of all the females, storage date, coloration and number of eggs, weight and coloration of gonad and number of hatched larvae were noted. With respect to average fecundity (F) by length classes, the lowest and highest number of eggs observed was 696 and 1,554, respectively. As for fecundity by weight classes, the lowest number of eggs observed was 760 and the highest, 1,690. The highest number of eggs observed individually per hatching was 2,193. Average fecundity/total length (L) and average fecundity/total weight (W) may be expressed by a linear relationship. The adjusted equations are: F = -411.6 + 203.1 L (p 0.0001) and F = 566.4 + 157.3 W (p 0.0001), respectively. In the analysis of average fertility (N) per length classes, the lowest and highest number of larvae observed was 374 and 1,301, respectively. With respect to fertility per weight classes, the lowest number of larvae was 581 and the highest, 1,391. In this work, the maximum number of larvae observed per hatching for females kept in laboratory was 2,594. Average fertility/total length and average fertility/total weight may be expressed by a linear relationship. The adjusted equations are: N = -1042.7 + 264.9 L (p 0.0002); N = 384.1 + 160.3 W (p 0.003). From these results we can deduced that fecundity and fertility of M. amazonicum are lower than ones commercial species, nevertheless it can be captured during all year long. The number of captured prawns was large in the months whose level of water was low; the inverse was observed in the months that the river was with a high volume of water.

No Brasil, os estudos com espécies nativas de camarões de água doce foram interrompidos em decorrência da importação de Macrobrachium rosenbergii. Entretanto, é necessário continuar as investigações com nossas espécies, com o objetivo de desenvolver tecnologia adequada à nossa realidade e, em um futuro próximo, de permitir aos carcinicultores outras opções para cultivo. O objetivo deste estudo foi determinar a fecundidade e a fertilidade de Macrobrachium amazonicum, capturado mensalmente de junho de 1999 a junho de 2001, no Rio Jaguaribe, em Itaiçaba, Ceará, Brasil. Após a coleta, os camarões foram transportados para o Laboratório de Ciências Biológicas, na Universidade Estadual do Ceará (Fortaleza, Ceará, Brasil). Foram selecionadas, aleatoriamente, 60 fêmeas ovígeras para a determinação da fecundidade. Os ovos aderidos aos pleópodes foram retirados, colocados em Solução de Gilson e estocados em álcool 70%. A fecundidade individual foi determinada a partir da contagem total dos ovos de cada fêmea. Para determinar a fertilidade, fêmeas ovígeras de M. amazonicum foram estocadas individualmente em aquários de vidro de 10 L. Após a eclosão, as larvas foram sifonadas e contadas. Os dados referentes ao comprimento e peso total de todas as fêmeas, à data de estocagem, à coloração e número de ovos, ao peso e coloração das gônadas e ao número de larvas eclodidas foram registrados. O menor e o maior número de ovos observados por classes de comprimento foram de 696 e 1.554, respectivamente. Para a fecundidade por classes de peso, o menor número de ovos observados foi de 760 e o maior, de 1.690. O número mais elevado de ovos observados individualmente por desova foi 2.193. Fecundidade média/comprimento total (L) e fecundidade média/peso total (W) podem ser expressas por relação linear. As equações ajustadas são F = -411,6 + 203,1 L (p 0,0001) and F = 566,4 + 157,3 W (p 0,0001), respectivamente. Na análise da fertilidade (N) por classes de comprimento, o menor e o maior número de larvas observados foram 374 e 1.301, respectivamente. Quanto à fertilidade por classes de peso, o menor número de larvas foi de 401 e o maior, de 1.231. Neste trabalho, o número máximo de larvas observado por desova para fêmeas mantidas em laboratório foi de 2.594. Fertilidade média/comprimento total e fertilidade média/peso total podem ser expressos por relação linear. As equações ajustadas são: N = -1042,7 + 264,9 L (p 0,0002); N = 384,1 + 160,3 W (p 0,003). A partir desses resultados, podemos deduzir que M. amazonicum apresenta menor fecundidade e fertilidade que outras espécies comercializadas, podendo ser capturado durante todo o ano. O número de camarões foi variável, a maior quantidade foi observada nos meses em que o rio apresentou menor nível, e vice-versa.