RESUMO

Experimental infections have been used to better comprehend the immune system of organisms, and to probe for additives that generate greater resistance and help reduce antibiotic use in aquaculture. We compared the immune response of juveniles of the Caribbean spiny lobster, Panulirus argus, infected naturally with Panulirus argus virus 1 (PaV1) versus organisms infected experimentally, to determine the analogy between both infectious processes. The immunological response was measured by hemagglutination activity, hemocyte count, and total phenoloxidase activity in plasma and hemocytes in 211 individuals that were either naturally infected (110), or had been injected with viral inoculum and followed for six months (101). The samples were classified into the following four groups according to the severity of the infection: 0, uninfected; 1, lightly; 2, moderately; and 3, severely infected), which was determined on the basis of PCR and histological criteria. A permutational MANOVA showed that both the origin (natural and experimental), and the severity of the infection contributed significantly to explain the variation in the immune response of lobsters. The lack of significance of the interaction term indicated that the immunological response changed with the severity of the infection in a similar way, regardless of its origin. The results of the present study suggest that the experimental viral infection of PaV1 produces a defense response similar to the natural pathways of contagion, and provides the bases to validate an immunological challenge protocol for the first time in crustaceans. The discussion includes the perspective of the conceptual models of immune response within an ecological context.

RESUMO

The spiny lobster Panulirus argus (Latreille, 1804) is currently affected by an unenveloped, icosahedral, DNA virus termed Panulirus argus virus 1 (PaV1), a virulent and pathogenic virus that produces a long-lasting infection that alters the physiology and behaviour of heavily infected lobsters. Gut-associated microbiota is crucial for lobster homeostasis and well-being, but pathogens could change microbiota composition affecting its function. In PaV1 infection, the changes of gut-associated microbiota are yet to be elucidated. In the present study, we used high-throughput 16S rRNA sequencing technology to compare the bacterial microbiota in intestines of healthy and heavily PaV1-infected male and female juveniles of spiny lobsters P. argus captured in Puerto Morelos Reef lagoon, Quintana Roo, Mexico. We found that basal gut-associated microbiota composition showed a sex-dependent bias, with females being enriched in amplicon sequence variants (ASVs) assigned to Sphingomonas, while males were enriched in the genus Candidatus Hepatoplasma and Aliiroseovarius genera. Moreover, the alpha diversity of microbiota decreased in PaV1-infected lobsters. A significant increase of the genus Candidatus Bacilloplasma was observed in infected lobsters, as well as a significant decrease in Nesterenkonia, Caldalkalibacillus, Pseudomonas, Cetobacterium and Phyllobacterium. We also observed an alteration in the abundances of Vibrio species. Results from this study suggest that PaV1 infection impacts intestinal microbiota composition in Panulirus argus in a sex-dependent manner.

Assuntos

RESUMO

The Caribbean spiny lobster Panulirus argus (Latreille, 1084) sustains economically valuable fisheries throughout the wider Caribbean region. This species is currently affected by the pathogenic virus Panulirus argus Virus 1 (PaV1) that causes a systemic and chronic-degenerative infection in juvenile spiny lobsters P. argus. To date, there is no available information regarding the host alterations induced by this pathogen at the molecular level. In the present study, comparative proteomic analyses of the changes in the hepatopancreas between infected and non-infected juvenile lobsters were analyzed by isobaric tags for relative and absolute quantitation (iTRAQ) coupled to synchronous precursor selection (SPS)-based MS3. We identified a total of 636 proteins, being 68 down-regulated and 71 up-regulated proteins. Among the down-regulated proteins, we identified several enzymes involved in the metabolism of hormones and lipids, digestive proteases and glycosidases, while proteins associated with the histone core, protein synthesis, immune response and RNA regulation were up-regulated. Several misregulated enzymes involved in the regulation of neuromodulators were also identified. RT-qPCR assays were used to validate the expression of transcripts encoding for selected differential proteins that were in concordance to proteomic data, as well as the tendency observed in the enzymatic activities of trypsin, chymotrypsin, and glycosidase. In a similar way, we observed glycogen reduction in muscle, and an increase in plasma acylglycerides and glucose, which may be explained by proteomic data. This study provides the first insight into the molecular changes in the hepatopancreas of Caribbean spiny lobsters associated to PaV1 infection. Data provided herein would help to clarify the origin of the molecular misregulations observed at macroscopic level in this host-pathogen interaction.

RESUMO

Panulirus argus virus 1 (PaV1) affects wild populations of Caribbean spiny lobsters. PaV1 can be lethal but shows predilection for juvenile lobsters. Because P. argus is one of the most valuable fisheries around the wider Caribbean region, monitoring disease prevalence in local populations is desirable. Diseased lobsters are easily recognized by their milky hemolymph, but this sign only becomes evident in advanced stages of infection. Other methods have been developed to detect PaV1, but are less practical for long-term monitoring of patterns of infection in populations. A previous study estimated the validity measures (sensitivity and specificity) of detection of PaV1 infection by observed clinical signs against endpoint PCR assays, using a representative sample of lobsters comprising mainly subadults and adults from a commercial fishing area. In the present study, these validity measures were estimated in a similar manner for a different population comprising mainly juveniles from a protected nursery area. We obtained virtually the same sensitivity and specificity values (0.48 and 1, respectively) for observed clinical signs as in the previous study (0.51 and 1, respectively), confirming the validity of applying a simple 2× correction factor to monitor the patterns of PaV1 infection over time based on more easily conducted visual assessments of a representative sample of the population.

Assuntos

RESUMO

Spiny lobsters have a protracted pelagic, oceanic larval phase. The final larval stage metamorphoses into a non-feeding postlarva (puerulus) that actively swims towards the coast to settle in shallow habitats and does not resume feeding until after the molt into the first-stage juvenile. Therefore, the body dimensions and nutritional condition of both settled pueruli and first juveniles are likely to vary over time, potentially playing a crucial role in the recruitment to the benthic population. We compared carapace length (CL), height (CH), and width (CW); total length (TL), and body weight (W) between pueruli and first juveniles of the Caribbean spiny lobster, Panulirus argus, as well as morphometric relationships between both developmental stages. Except for CL, all other dimensions were larger in first juveniles, but more markedly CH and W. The slopes of the CH vs CL, CW vs CL, and W vs CL regressions differed significantly between stages, and all log-transformed relationships showed isometry in both stages, except for the CH vs CL relationship, which showed positive allometry. These results reflect a morphological change from the flatter, more streamlined body of the puerulus, to the heavier, more cylindrical body of the juvenile. We also analyzed seasonal variations in CL, W, the W/CL index (a morphometric condition index), and a modified W/CL index (i.e. after controlling for a significant effect of CL) of both stages using individuals monthly collected over 12 consecutive seasons (Autumn 2010-Summer 2013). In both stages, all three variables exhibited significant seasonal variation. For pueruli, the modified W/CL index differed from average in only two seasons, winter 2011 (higher) and summer 2013 (lower), but showed great within-season variation (larger coefficients of variation, CV), potentially reflecting variability in nutritional condition of larvae prior to metamorphosis and in the distances swum by individual pueruli to the settlement habitats. For first juveniles, the modified W/CL index was higher than average in winter and spring 2011, and lower in autumn 2011 and winter 2012, but showed less within season variation (smaller CVs), suggesting a combination of carry-over effects of puerulus condition and effects of local conditions (e.g., food availability and predation risk). These findings warrant further investigation into factors potentially decoupling settlement from recruitment processes.

RESUMO

As other spiny lobsters, Panulirus argus is supposed to use preferentially proteins and lipids in energy metabolism, while carbohydrates are well digested but poorly utilized. The aim of this study was to evaluate the effect of dietary carbohydrate level on digestion and metabolism in the spiny lobster P. argus. We used complementary methodologies such as post-feeding flux of nutrients and metabolites, as well as measurements of α-amylase expression and activity in the digestive tract. Lobsters readily digested and absorbed carbohydrates with a time-course that is dependent on their content in diet. Lobster showed higher levels of free glucose and stored glycogen in different tissues as the inclusion of wheat flour increased. Modifications in intermediary metabolism revealed a decrease in amino acids catabolism coupled with a higher use of free glucose as carbohydrates rise up to 20%. However, this effect seems to be limited by the metabolic capacity of lobsters to use more than 20% of carbohydrates in diets. Lobsters were not able to tightly regulate α-amylase expression according to dietary carbohydrate level but exhibited a marked difference in secretion of this enzyme into the gut. Results are discussed to highlight the limitations to increasing carbohydrate utilization by lobsters. Further growout trials are needed to link the presented metabolic profiles with phenotypic outcomes.

RESUMO

Cymatocarpus solearis, a brachycoeliid trematode that parasitizes sea turtles, uses spiny lobsters Panulirus argus as second intermediate hosts. We examined variability in infection by C. solearis in Bahía de la Ascensión, Mexico, a tropical bay with a highly productive fishery for P. argus that is based on the extensive use of casitas (large artificial shelters), which can harbor multiple juveniles and adults of this gregarious lobster species. We sampled 3956 lobsters from 466 casitas distributed over three bay zones within two closed seasons and one fishing season. In these lobsters (9.5-115.2mm carapace length, CL), the average infection prevalence was 11.7% but the probability of infection increased significantly with size. Prevalence varied with season but was consistently higher in one zone than in the other two zones. Infection with C. solearis was negatively related with clinical infection with Panulirus argus Virus 1 (PaV1). We also sampled 405 lobsters from the commercial catch obtained throughout the bay at the onset of the fishing season. In these relatively larger lobsters (70.3-168.0mm CL), average prevalence of C. solearis was higher (23.5%) but was not affected by lobster size or sex. Encysted metacercariae occurred in both abdominal and cephalothoracic muscles. The effects of C. solearis on phenotypic traits of P. argus that may potentially impact the host population dynamics and fisheries remain to be investigated.

Assuntos

RESUMO

The objective of this work was to investigate the species composition and the catch rates of the lobster fishery with traps in Pernambuco. Besides the red (Panulirus argus) and the green (Panulirus laevicauda) spiny lobsters, six other species of crustacean, 34 fish species and two molluscs species were also caught. Catch rates of lobsters were higher when traps were deployed in shallow waters northward of Olinda coast. Catch rate of lobsters decreased from the beginning to the end of the harvest season, when catch rates of fishes surpassed that of lobsters. Catch rates of mollusks were low. The high diversity and the ecological and economic importance of the bycatch species highlight the need for monitoring the fishery with traps, as well as for studies on the potential production and vulnerability of those species caught together with lobsters.(AU)

O objetivo desse trabalho foi obter informações sobre a composição específica e as taxas de captura na pesca da lagosta com covos no litoral central de Pernambuco. Além das lagostas vermelha (Panulirus argus) e verde (Panulirus laevicauda), foram capturadas seis espécies de crustáceos, 34 espécies de peixes e duas espécies de moluscos. As taxas de captura das lagostas foram maiores nos lances de pesca realizados em águas mais rasas e posicionados mais ao norte do litoral de Olinda. Houve um decréscimo das taxas de captura das lagostas do início ao final da temporada de pesca, quando as taxas de captura de peixes foram maiores. As taxas de captura dos moluscos foram reduzidas. A grande diversidade e a importância econômica e ecológica da fauna acompanhante reforçam a necessidade de monitoramento da pescaria com covos e o estudo dos potenciais de produção e da vulnerabilidade das espécies capturadas junto com as lagostas.(AU)

Assuntos

RESUMO

The objective of this work was to investigate the species composition and the catch rates of the lobster fishery with traps in Pernambuco. Besides the red (Panulirus argus) and the green (Panulirus laevicauda) spiny lobsters, six other species of crustacean, 34 fish species and two molluscs species were also caught. Catch rates of lobsters were higher when traps were deployed in shallow waters northward of Olinda coast. Catch rate of lobsters decreased from the beginning to the end of the harvest season, when catch rates of fishes surpassed that of lobsters. Catch rates of mollusks were low. The high diversity and the ecological and economic importance of the bycatch species highlight the need for monitoring the fishery with traps, as well as for studies on the potential production and vulnerability of those species caught together with lobsters.

O objetivo desse trabalho foi obter informações sobre a composição específica e as taxas de captura na pesca da lagosta com covos no litoral central de Pernambuco. Além das lagostas vermelha (Panulirus argus) e verde (Panulirus laevicauda), foram capturadas seis espécies de crustáceos, 34 espécies de peixes e duas espécies de moluscos. As taxas de captura das lagostas foram maiores nos lances de pesca realizados em águas mais rasas e posicionados mais ao norte do litoral de Olinda. Houve um decréscimo das taxas de captura das lagostas do início ao final da temporada de pesca, quando as taxas de captura de peixes foram maiores. As taxas de captura dos moluscos foram reduzidas. A grande diversidade e a importância econômica e ecológica da fauna acompanhante reforçam a necessidade de monitoramento da pescaria com covos e o estudo dos potenciais de produção e da vulnerabilidade das espécies capturadas junto com as lagostas.

Assuntos

RESUMO

A lagosta tem papel de destaque no setor pesqueiro nacional, sendo o principal recurso pesqueiro da região Nordeste e 95% desta produção destina-se ao mercado internacional. O grau de frescor do pescado é um dos aspectos mais importantes para determinar a qualidade do pescado, e frequentemente se recorre a métodos sensoriais, físicos, bioquímicos e microbiológicos. O objetivo deste trabalho foi avaliar a qualidade da lagosta inteira armazenada em gelo através do Método de Índice de Qualidade (MIQ), que permite a determinação rápida e eficiente do grau de frescor do pescado. Os pontos de deméritos foram designados aos atributos sensoriais selecionados de acordo com sua importância. Durante o armazenamento foram realizadas determinações do Nitrogênio das Bases Voláteis Totais (NBVT), pH e análises microbiológicas (Coliformes Termotolerantes, Salmonella spp. e Staphylococcus aureus). O Índice de Qualidade (IQ) variou de zero (máximo frescor) a 14 (perda total do frescor) atingindo o limite de aceitabilidade para consumo (IQ = 6,3), o que equivale a um período de 7 dias. O valor do N-BVT variou de 19,69 a 29,63 mg 100g-1, e o pH variou de 6,91 a 7,03 no primeiro e 17º dia de armazenamento, respectivamente. Os resultados microbiológicos atenderam aos padrões microbiológicos estabelecidos pela legislação brasileira.

The lobster has an important role in the national fisheries sector, the main fishing resourc e in the Northeast and 95% of this production is intended for the international market. The seafood freshness degree is one of the most important in determining the seafood quality, and often uses a sensorial, physical, biochemical and microbiological methods. The objective of this study was to evaluate the whole lobster quality stored on ice through the Quality Index Method (QIM), which allows rapid and efficient determination of the seafood freshness. The demerits points were assigned to the sensory attributes selected according to their importance. During storage the total volatile bases nitrogen (TVB - N), pH and microbiological (fecal coliform, Salmonella spp. and Staphylococcus aureus ) were made. The Quality Index (IQ) ranged from zero (maximum freshness) to 14 (total loss of freshness) reached the acceptable limit for consumption (IQ = 6.3), which corresponds to a period of 7 days. The value of the TVB - N ranged from 19.69 to 29.63 mg 100g - 1 , and the pH ranged from 6.91 to 7.03 in the first and 17th day of storage, respectively. The microbiological results met the microbiological standards e stablished by Brazilian legislation.

Assuntos

RESUMO

Variations of the nutritional condition of lobsters Panulirus argus (Decapoda: Palinuridae) in Eastern region of the Gulf of Batabanó, Cuba. Nutritional condition can affect survival and growth rate of crustaceans, and this is mostly affected by habitat conditions. This study describes the space-temporary nutritional changes in this commercially important species. With this aim, the variations in the nutritional condition (K) of lobsters from four zones (1, 2, 4 and 5) in the Gulf of Batabanó, Cuba, were determined. For this, the weight/length ratio (K=Pt/Lt) was calculated using animals captured in 1981 and 2010. The nutritional condition between areas and sexes, and years and sexes, was contrasted by a bifactorial ANOVA, and the overall length and weight of lobsters were compared using a t-Test for independent samples and unifactorial ANOVA. It was found that the nutritional condition was significantly greater in males than in females. In addition, significant variations between zones were detected for both years. Nutritional condition of lobsters from Zone five was the highest for 1981, while it was Zone two for 2010. Lobsters nutritional state showed significant variations between years, being greater in 1981 (2.34±0.84g/mm) than in 2010 (1.96±0.49g/mm). The inter-zones variations as well as the inter-annual ones seem to be related to the reported variations of the bottom type and the vegetation cover. Seasonal variations in the abundance and distribution of benthic organisms, that constitute food for lobsters, could also be influencing. The differences between sexes, however, were assumed as a consequence of the methodology used and the sexual dimorphism of the species. Due to other K estimation methods, that do not include morphometric measurements, these differences were not detected. We suggested that the P. argus nutritional condition is a good estimator of the habitat condition. Besides, according to the applied K estimation methodology, it was found that different groups of lobsters that have resemblant nutritional condition, did not necessarily observe similarities in the overall mean length or weight, so they could exist under different habitat conditions.

En Cuba, la región del Golfo de Batabanó es la más importante zona de pesca de langosta debido a que de ella se extrae anualmente alrededor del 70% de la captura nacional. Con el objetivo de determinar variaciones espacio-temporales en la condición nutricional (K) de langostas Panulirus argus del Golfo de Batabanó, Cuba, se calculó dicha condición mediante una relación pesolargo (K=Pt/Lt), para lo que se utilizaron ejemplares de cuatro zonas (uno, dos, cuatro y cinco) del este del golfo, capturados en los años 1981 y 2010. Se encontró que en todos los casos analizados la condición nutricional fue significativamente mayor en machos que en hembras. Se detectaron variaciones significativas entre zonas en 1981 y 2010. También entre años el estado nutricional de las langostas presenta variaciones significativas, de manera que en 1981 (2.34±0.84g/mm) fue mayor que en 2010 (1.96±0.49g/mm). Tanto las variaciones interzonales como las interanuales parecen estar relacionadas con variaciones reportadas en el tipo de fondo y la cobertura vegetal. Variaciones estacionales en la abundancia y distribución de organismos bentónicos que constituyen alimento para las langostas también podrían estar influyendo. Las diferencias entre sexos en cambio, se suponen consecuencia de la metodología utilizada y del dimorfismo sexual característico de esta especie, por cuanto otros métodos de estimación de K que no involucran mediciones morfométricas, no detectan estas diferencias.

Assuntos

RESUMO

Influence of lunar cycle on catches of spiny lobster Panulirus argus (Decapoda: Palinuridae) in the Gulf of Batabanó, Cuba. Many biological processes such as reproductive and migratory behaviours have been associated with moon cycles. In this study, the nocturnal light levels associated with lunar cycle (INT) were correlated with daily catch rate of lobster P. argus, during seven lunar months of 2002 fishing period, to determine a possible relationship between these variables. The lobster catches were obtained from three fishing companies that develop their activities in the Gulf of Batabanó: EPICOL that fishes in Coloma area; PESCAHABANA in Batabanó area and PESCAISLA in Isla area. Daily catch per boat (CDB) was used as a measurement of daily catch variations (catch rate). The correlation was analyzed showing it in chronological graphs based on average of CDB per lunar phases, comparing lobster catch rate per lunar phases -with the Kruskal-Wallis test-. Spearman rank correlation coefficient and cross correlation techniques were also applied. Similarities between lobster catch rate and the lunar cycle were not found. Spearman rank correlation coefficient was modularly smaller than 0.1 in all cases and demonstrated quantitatively that correlation between CDB and INT does not exist. Kruskal-Wallis test detected differences only in Batabanó area but not when making the analyses for the whole Gulf of Batabanó. Finally, the cross correlations do not detected significance in any zone, as well. It is concluded that, in opposition to what other authors have reported, the catch rates of P. argus and the lunar cycle did not show significant correlation in the Gulf of Batabanó. This trend was independent of the fishing art, which varied according to the time of the year that was analyzed. Rev. Biol. Trop. 59 (1): 207-216. Epub 2011 March 01.

Muchos procesos biológicos tales como los comportamientos reproductivos y migratorios se han asociado con los ciclos de la luna. Con el objetivo de determinar la relación entre las capturas de langosta espinosa Panulirus argus (Decapoda: Palinuridae) y el ciclo lunar, en la zona del Golfo de Batabanó, se correlacionaron los niveles de iluminación nocturna del ciclo lunar (INT) con la captura diaria por barco (CDB) durante siete meses lunares correspondientes al período de pesca del 2002. Los datos de captura provinieron de las tres empresas pesqueras que realizan su actividad en la zona del Golfo de Batabanó. La relación entre el ciclo lunar y las capturas de langostas fue examinada mediante varios procedimientos estadísticos. Los primeros gráficos realizados, cualitativos, mostraron que no existe relación entre las tasas de captura y el ciclo lunar. Los coeficientes de Spearman calculados, modularmente menores que 0.1 en todos los casos, demostraron cuantitativamente que no existe correlación entre las mencionadas variables. La prueba de Kruskal-Wallis detectó diferencias sólo en una de las tres áreas estudiadas. Las correlaciones cruzadas no detectaron significación en ninguna de las zonas, con coeficientes de correlación cruzada modularmente inferiores a 0.1. A diferencia de lo reportado por otros autores, las capturas de P. argus y el ciclo lunar no presentan correlación significativa en el Golfo de Batabanó.

Assuntos

RESUMO

Puerulus of Panulirus argus settlement is generally in the shallows and typically reside solitary in branched red algae Amansia sp. This type of habitat may be found in many areas of the  Ceara State Coast,  where macroalgae Amansia sp. with associated other genera of macroalgae and crevice shelters function as habitat for young juvenile spiny lobster. The objective of this work was to help to explain the settlement of puerulus and juvenile of P. argus in the coast of Ceará, Brazil and their behaviour.

Puerulus de Panulirus argus assentam geralmente em locais rasos, tipicamente e solitariamente em ramos de algas vermelhas como a Amansia sp. Este tipo de habitat pode ser encontrado em muitas áreas da Costa do Estado do Ceará, onde a macroalga Amansia sp. associado com outros gêneros de macroalgas e fendas nas rochas funcionam como habitat para juvenis. O objetivo desse trabalho foi contribuir no conhecimento do comportamento e habitat de puerulus e juvenil de P. argus no Brasil.  

RESUMO

Puerulus of Panulirus argus settlement is generally in the shallows and typically reside solitary in branched red algae Amansia sp. This type of habitat may be found in many areas of the  Ceara State Coast,  where macroalgae Amansia sp. with associated other genera of macroalgae and crevice shelters function as habitat for young juvenile spiny lobster. The objective of this work was to help to explain the settlement of puerulus and juvenile of P. argus in the coast of Ceará, Brazil and their behaviour.

Puerulus de Panulirus argus assentam geralmente em locais rasos, tipicamente e solitariamente em ramos de algas vermelhas como a Amansia sp. Este tipo de habitat pode ser encontrado em muitas áreas da Costa do Estado do Ceará, onde a macroalga Amansia sp. associado com outros gêneros de macroalgas e fendas nas rochas funcionam como habitat para juvenis. O objetivo desse trabalho foi contribuir no conhecimento do comportamento e habitat de puerulus e juvenil de P. argus no Brasil.

Assuntos