Reproducción y limitaciones de pesca recomendadas para el caracol marino Hexaplex princeps (Neogastropoda: Muricidae) en Guerrero, México / Reproduction and recommended fishing limitations for the marine snail Hexaplex princeps (Neogastropoda: Muricidae) in Guerrero, Mexico

Abstract Introduction: The snail Hexaplex princeps is the most important gastropod in the fishery of Guerrero, but capture is not legally regulated for lack of enough studies about its reproduction, growth and other fishing aspects. Objective: To assess fishery data for H. princeps in Guerrero. Methods: From October 2016 to December 2017, we analyzed histological samples of the gonads from 6 to 13 individuals per month. We also collected data on pre-reproductive organisms captured in Costa Chica (2013 and 2014), Costa Grande (2017) and Acapulco (2019 and 2020). Results: Both sexes have five stages of gonadal development; most reproductive activity was from December to July, related to sea surface temperatures of 26 to 28 °C. The LC M in females was 94.1 mm (males: 86.1 mm). There was a high percentage of juvenile organisms in the catches (88.6 %). Conclusions: To let these snails reproduce at least once, we recommend a fishing ban from December to July, and that the minimum size of commercial capture be set at 94.1 mm.

Resumen Introducción: El caracol Hexaplex princeps es el gasterópodo más importante en la pesquería de Guerrero, pero su captura no está regulada legalmente por falta de suficientes estudios sobre su reproducción, crecimiento y otros aspectos de la pesca. Objetivo: Evaluar los datos de pesca de H. princeps en Guerrero. Métodos: De octubre 2016 a diciembre 2017, analizamos muestras histológicas de las gónadas de 6 a 13 individuos por mes. También recolectamos datos sobre organismos pre-reproductivos capturados en Costa Chica (2013 y 2014), Costa Grande (2017) y Acapulco (2019 y 2020). Resultados: Ambos sexos tienen cinco etapas de desarrollo gonadal; la mayor actividad reproductiva fue de diciembre a julio, relacionada con las temperaturas superficiales del mar, que se encuentran entre 26 y 28 °C. El LC M en hembras fue de 94.1 mm (machos: 86.1 mm). Hubo un alto porcentaje de organismos juveniles en las capturas (88.6 %). Conclusiones: Para que estos caracoles se reproduzcan al menos una vez, se recomienda una veda de diciembre a julio y que la talla mínima de captura comercial se fije en 94.1 mm.

Actuotaphonomic model of the mollusk fauna of Laguna de Mandinga, Veracruz, Mexico / Modelo actuotafonómico de la fauna de moluscos de Laguna de Mandinga, Veracruz, México

Introduction: The taphonomic attributes of a faunal assemblage provide information about which agents affect the distribution and preservation of ancient or newly formed biogenic materials during depositional and post-depositional processes. Actuotaphonomy thus is a valuable tool for reconstructing fossil communities because it establishes analogies between observable processes in the present and those that happened in the past. Objective: The taphonomic attributes of a marginal marine environment were analyzed to assess the origin of fragmentation, bioerosion, and encrustation processes and the role of these characteristics in the deterioration of current sediment accumulations of mollusks (gastropods and bivalves). Methods: The material studied was collected from a shell-remain accumulation called "El Conchal" in the Laguna de Mandinga, Veracruz, a lagoonal complex located in the Gulf of México. Taphonomic analysis included fragmentation, bioerosion, and encrustation features on recent gastropods and bivalve's shells. The categories of each attribute were classified in three degrees: poor, regular and good. The analysis was performed only in complete shells. Results: A bulk sample of 1 697.9 g was processed, recovering 1 165 complete specimens, of which 5 genera of bivalves and 4 genera of gastropods were identified. The fragmentation and bioerosion were classified as regular (grade 1), this may be the results of the water energy in the environment, that permits a constant rework, and exhumation of the remains at the lagoon's water-sediment interface; meanwhile, three eroders were identified to ichnogenus level: Entobia, Oichnus, and Caulostrepsis, being Caulostrepsis the least abundant. The encrustation was classified as poor (grade 2); the result can be interpreted based on the ecosystem intrinsic conditions that do not allow many encrusting organisms to develop properly. The encrusters are represented by calcareous organisms including bryozoans, serpulids tubes, and barnacles. The results yielded an actuotaphonomic model that could be applicable to analogous ecosystems in Laguna de Mandinga (Mandinga Lagoon), in Veracruz, Mexico. Conclusions: In marine marginal environments as in lagoon areas the encrustation does not have an important role in the preservation or destruction of shelly assemblages, being taphonomically more important than fragmentation and bioerosion as potentially destructive agents that can be a source of loss of fidelity in the fossil record.

Introducción: Los atributos tafonómicos de los conchales proveen información acerca de cuáles agentes afectan la distribución y preservación de la acumulación de materiales biogénicos recientes o fósiles, especialmente durante las etapas deposiconales y postdeposicionales. La actuotafonomía es una herramienta valiosa para la reconstrucción de las comunidades fósiles, para establecer analogías entre los procesos observables en el presente con los que ocurrieron en el pasado. Objetivos: Evaluar el impacto de los rasgos tafonómicos y su papel en la formación de los conchales en ambientes de lagunas costeras. Métodos: El material estudiado fue recolectado en una acumulación de restos de conchas llamado "El Conchal" en la Laguna de Mandinga, Veracruz, un complejo lagunar ubicado en el Golfo de México. El análisis tafonómico incluye las características tafonómicas de fragmentación, bioerosión e incrustación en conchas de gasterópodos y bivalvos recientes. Las categorías de cada atributo se clasificaron en tres grados: pobre, medio y alto. El análisis fue realizado solo en conchas completas. Resultados: Se procesaron 1 697.9 g de sedimentos, recuperando 1 165 ejemplares completos, de los cuales se identificaron 5 géneros de bivalvos y 4 géneros de gasterópodos. La fragmentación y bioerosión se clasificaron como un "grado regular", esto puede ser el resultado de la energía del agua en el ambiente, que permite el constante retrabajo y la exhumación de los restos en la interfase agua-sedimento en la laguna; en tanto que, se identificaron tres erosionadores a nivel de género, estos corresponden a los icnogéneros: Entobia, Oichnus y Caulostrepsis, siendo Caulostrepsis el menos abundante. La incrustación mostró un "grado pobre"; el resultado puede interpretarse basado en las condiciones intrínsecas del ecosistema que no permiten que muchos incrustantes se desarrollen de la manera adecuada. Los incrustantes están representados por organismos calcáreos incluyendo briozoarios, tubos de serpúlidos y balanos. Se analizaron los atributos tafonómicos para generar un modelo actuotafonómico que pueda ser aplicable a ecosistemas análogos en el registro fósil. Conclusiones: En ambientes marino marginales como son las áreas lagunares la incrustación no tiene un papel importante en la preservación o destrucción de los conchales, siendo tafonómicamente más importante la fragmentación y bioerosión como agentes potencialmente destructivos que pueden ser un recurso de pérdida de la fidelidad en el registro fósil.

Growth Performance of the Mangrove Oyster Cultivated on the Amazon Coast

Abstract In the last decades the oyster faming stands out as the main mitigating measure to the decline of the fishery, as it presents socio-economic and environmental viability. However, for the success of the activity, it is necessary to understand the stages of cultivation, as well as the growth performance of the species to be cultivated. The present work aims to characterize the growth and survival of Crassostrea tulipa, cultivated on the Amazon coast. For this purpose, oysters were grouped by commercial size class (seed, juvenile, baby, average and masters) and compared the growth rates and their relationships with the abiotic variables. There was no difference in the average growth between the oyster classes, however, when comparing them in the total and percentage growth rates, a higher performance was observed in the oysters classified by juvenile and seed, respectively. The relationship of salinity to oyster growth was evidenced only in the class of juvenile oysters. The cultivation time required to obtain native oysters in the commercial size varied between four and seven months, being inferior to those found in other Brazilian regions.

Deep sequencing of small RNAs reveals the repertoire of miRNAs and piRNAs in Biomphalaria glabrata

BACKGROUND Biomphalaria glabrata snails are widely distributed in schistosomiasis endemic areas like America and Caribe, displaying high susceptibility to infection by Schistosoma mansoni. After the availability of B. glabrata genome and transcriptome data, studies focusing on genetic markers and small non-coding RNAs have become more relevant. The small RNAs have been considered important through their ability to finely regulate the gene expression in several organisms, thus controlling the functions like cell growth, metabolism, and susceptibility/resistance to infection. OBJECTIVE The present study aims on identification and characterisation of the repertoire of small non-coding RNAs in B. glabrata (Bgl-small RNAs). METHODS By using small RNA sequencing, bioinformatics tools and quantitative reverse transcription polymerase chain reaction (RT-qPCR), we identified, characterised, and validated the presence of small RNAs in B. glabrata. FINDINGS 89 mature miRNAs were identified and five of them were classified as Mollusk-specific. When compared to model organisms, sequences of B. glabrata miRNAs showed a high degree of conservation. In addition, several target genes were predicted for all the mature miRNAs identified. Furthermore, piRNAs were identified in the genome of B. glabrata for the first time. The B. glabrata piRNAs showed strong conservation of uridine as first nucleotide at 5' end, besides adenine at 10th position. Our results showed that B. glabrata has diverse repertoire of circulating ncRNAs, several which might be involved in mollusk susceptibility to infection, due to their potential roles in the regulation of S. mansoni development. MAIN CONCLUSIONS Further studies are necessary in order to confirm the role of the Bgl-small RNAs in the parasite/host relationship thus opening new perspectives on interference of small RNAs in the organism development and susceptibility to infection.

Ocotea pulchellaas an alternative against schistosomiasis: chemical analysis, development of nanoemulsion and biological control activity / Ocotea pulchellacomo una alternativa ante esquistosomiasis: análisis químico, desarrollo de una nanoemulsión y actividad en control biológico

The aim of this work was to evaluate the potential of the essential oil (EO) from Ocotea pulchella leaves as an alternative in the control of schistosomiasis. It was tested O. pulchella EO nanoformulation to assess its activity against adult Biomphalaria glabrata, their spawning and Schistossoma mansoni cercariae. Additionally, the EO chemical composition was investigated by gas-chromatography. Nanoemulsion were elaborated by the low energy method. The adult mollusks, their spawning and cercariae were placed in contact with nanoemulsion to calculate lethal concentrations. Myristicin, bicyclogermacrene and α-Pinene were the main substances in the EO. Nanoemulsion caused mortality of adult B. glabrata, its egg embryos and S. mansoni. These results suggest the use of this nanoemulsion as an alternative in the control of the schistosomiasis cycle.

El objetivo de este trabajo fue evaluar el potencial de los aceites esenciales (AE) de las hojas de Ocotea pulchellacomo una alternativa en el control de esquistosomiasis. Se probó una nanoformulación de AE de O. pulchellapara evaluar su actividad ante adultos de Biomphalaria glabrata, sus huevos y cercarías de Schistossoma mansoni. La nanoemulsión fue elaborada por el método de baja energía. Los moluscos adultos, sus huevos y cercarías se colocaron en contacto con la nanoemulsión para calcular concentraciones letales. Los compuestos mayoritarios en el AE fueron miristicina, biciclogermacreno y α-pineno. La nanoemulsión causó mortalidad en adultos de B. glabrata, sus huevos y a S. mansoni. Los resultados sugieren el uso de esta nanoemulsión como una alternativa en el control del ciclo de esquistosomiasis.

First report of detection of Toxoplasma gondii DNA in oysters (Crassostrea sp.) in the state of Maranhão / Primeiro relato da detecção de DNA de Toxoplasma gondii em ostras (Crassostrea sp.) no Estado do Maranhão

Abstract The aim of this study was to report on detection of Toxoplasma gondii DNA in oysters (Crassostrea sp.) in the state of Maranhão. To conduct this study, 200 farmed oysters were acquired in the municipality of Raposa and 100 in Paço do Lumiar; and a further 100 oysters were taken from the natural stock in the municipality of Primeira Cruz. This total of 400 specimens sampled was divided into 80 pools composed of five animals each. The gills and visceral mass of each oyster were removed for DNA extraction (per pool of oysters), using a commercial kit. The nested PCR technique (with the primer SAG-1) was then used to investigate any presence of protozoa. This molecular technique demonstrated the presence of DNA of T. gondii in 2.5% of the pools of oysters (n = 2/80): these oysters were exclusively from farms. The results from this study allow the conclusion that oysters of the genus Crassostrea that are farmed in the state of Maranhão are capable of filtering oocysts of T. gondii and maintaining them in their tissues. They are therefore potential sources of contamination for humans and other animals.

Resumo: Objetivou-se com este estudo relatar a detecção do DNA de Toxoplasma gondii em ostras (Crassostrea sp.) no estado do Maranhão. Para a realização do estudo foram adquiridas 200 ostras de cultivo do município de Raposa, e 100 de Paço do Lumiar, além de 100 ostras extraídas de estoque natural do município de Primeira Cruz. Do total de 400 exemplares amostrados, formaram-se 80 pools em que cada pool foi constituído por cinco animais. De cada ostra foi procedida à retirada das brânquias e massa visceral, seguido da extração de DNA de cada pool de ostras, com a utilização de kit comercial. Posteriormente, realizou-se a pesquisa do protozoário por meio da técnica de nested PCR (primer SAG-1). Com a técnica molecular utilizada, foi diagnosticado o DNA do protozoário pesquisado em 2,5% (n=2/80) pools de ostras oriundas exclusivamente de cultivo. Com os resultados obtidos neste estudo, conclui-se que ostras do gênero Crassostrea sp., cultivadas no estado do Maranhão, são capazes de filtrar e manter nos seus tecidos oocistos de T. gondii, sendo, portanto, fontes potenciais de contaminação para seres humanos e outros animais.

Virulence genes in Escherichia coli isolates from commercialized saltwater mussels Mytella guyanensis (Lamarck, 1819) / Presença de genes de virulência em isolados de Escherichia coli provenientes de sururu Mytella guyanensis (Lamarck, 1819) comercializado

Abstract The isolation of Escherichia coli from food is a major concern. Pathogenic strains of these bacteria cause diseases which range from diarrhea to hemolytic-uremic syndrome. Therefore the virulence genes in E. coli isolates from the mussel ( Mytella guyanensis) commercialized in Cachoeira, Bahia, Brazil were investigated. Samples were purchased from four vendors: two from supermarkets and two from fair outlets. They were conditioned into isothermal boxes with reusable ice and transported to the laboratory for analysis. E. coli strains were isolated in eosin methylene blue agar, preserved in brain-heart infusion medium with 15% glycerol and stored at -20 °C, after microbiological analysis. Virulence genes in the isolated strains were identified by specific primers, with Polymerase Chain Reaction. Twenty-four isolates were obtained, with a prevalence of elt gene, typical from enterotoxigenic infection, in 75% of the isolates. The stx and bfpA genes, prevalent in enterohemorragic and enteropathogenic E. coli, respectively, were not detected. The occurrence of elt virulence-related gene in the E. coli isolates of Mytella guyanensis reveals urgent improvement in food processing, including good handling practices, adequate storage and cooking before consumption, to ensure consumer's health.

Resumo O isolamento de Escherichia coli a partir de alimentos é uma grande preocupação, pois cepas patogênicas desta bactéria podem causar desde diarreia até síndrome hemolítico-urêmica. Diante do exposto, o objetivo do trabalho foi pesquisar genes de virulência em isolados de Escherichia coli provenientes do sururu Mytella guyanensis comercializado na cidade de Cachoeira, Bahia, Brasil. As amostras foram adquiridas de quatro comerciantes, sendo duas de mercados e duas em pontos de venda na feira livre da cidade de Cachoeira, acondicionadas em caixas isotérmicas com gelo reutilizável e transportadas até o laboratório para a análise. Após a análise microbiológica, as cepas de Escherichia coli foram isoladas em ágar Eosina Azul de Metileno e preservadas em caldo Brian Heart Infusion e glicerol a 15% e mantidas a - 20° C. A identificação dos genes de virulência nas cepas isoladas foi realizada utilizando primers específicos, por meio da Reação em Cadeia da Polimerase. Foram obtidos 24 isolados de Escherichia coli, destes a prevalência do gene elt , característico de Escherichia coli enterotoxigênica, foi de 75% dos isolados. Não houve a detecção dos genes stx e bfpA nos isolados, os quais são prevalentes nas cepas de Escherichia coli enterohemorrágica e Escherichia coli enteropatogênica, respectivamente. A presença do gene elt relacionado à virulência de Escherichia coli nos isolados de Mytella guyanensis revela a necessidade da melhoria no processamento, incluindo boas práticas de manipulação, armazenamento adequado e cocção previa ao consumo, visando a garantia da saúde do consumidor.

Growth parameters of the invasive gastropod Melanoides tuberculata (Müller, 1774) (Gastropoda, Thiaridae) in a semiarid region, Northeastern Brazil

Melanoides tuberculata has invaded several aquatic ecosystems in the Neotropical region. This species shows high adaptive capacity and plasticity, establishing itself in several basins, promoting negative impacts on environments and native species. Here, we determine the growth parameters and the population structure of this species, in a semi-arid environment, in Northeast Brazil (Pernambuco state). Monthly captures were conducted at three types of substrate: site 1: soft bottom with macrophytes, site 2: soft bottom without macrophytes, and site 3: gravel and rocks. Shells were classified as occupied or empty, and their shell length (SL) and opening width (SW) were measured. The growth parameters of the von Bertalanffy’s model were estimated from the size-length frequency distribution using the ELEFAN I. Also, the maturity was verified, through the size at onset of maturity (SOM - 14.85 mm SL) proposed in the literature. A total of 1,013 individuals were collected, with shells varying from 7 to 39 mm SL and mean density of 84.42 (± 3.86) individuals m-2. The substrate with the largest number of mollusks was the site 1. Largest amount of empty shells was detected at site 3. Growth of M. tuberculata indicates rapid increment, with k = 0.56, L∞ = 42 mm and t0 = -0.26 years. The mean estimated age for the species was 0.95 years. According to the SOM, 86% of individuals sampled were considered mature.

Progress of research on biologically invasive medical molluscs in China / 中国血吸虫病防治杂志

Invasion of alien species has increasingly become a major environmental problem that damages human health, economic development and ecological security in China, which has been paid much attention. Until now, there have been 753 invasive species reported in China, and invasive medical molluscs include Pomacea canaliculata, Achatina fulica, and Biomphalaria straminea. This review summarizes the status of biologically invasive species in China, describes the species and distribution of invasive medical molluscs, analyzes the damages of the invasive medical molluscs-transmitted diseases, and proposes the preventive and control measures.

Progress of research on biologically invasive medical molluscs in China / 中国血吸虫病防治杂志

Invasion of alien species has increasingly become a major environmental problem that damages human health, economic development and ecological security in China, which has been paid much attention. Until now, there have been 753 invasive species reported in China, and invasive medical molluscs include Pomacea canaliculata, Achatina fulica, and Biomphalaria straminea. This review summarizes the status of biologically invasive species in China, describes the species and distribution of invasive medical molluscs, analyzes the damages of the invasive medical molluscs-transmitted diseases, and proposes the preventive and control measures.

Snail transmitters of schistosomiasis and other mollusks of medical and economic importance at the simplício queda única hydroelectric plant, southeast Brazil

Abstract INTRODUCTION This paper presents the results of an extensive survey of freshwater mollusks in the Simplício Queda Única Hydroelectric Development area, Southeast Brazil. METHODS Mollusks were collected between 2008 and 2013. All specimens were examined for the presence of larval trematodes. RESULTS In total, 12,507 specimens classified into 16 genera were obtained. Known snail vectors of schistosomiasis and fascioliasis and exotic species were identified, and new records are reported. CONCLUSIONS No specimens parasitized by larval trematodes of medical interest were detected. However, the results reinforce the importance of surveillance in study areas vulnerable to the occurrence of schistosomiasis transmission.

Distribution and density of the bivalve Anomalocardia brasiliana in the estuarine region of Northeastern Brazil / Distribuição e densidade do bivalve Anomalocardia brasiliana em região estuarina do semiárido do Nordeste do Brasil

Abstract The objective of this study was to analyze the density and distribution of the bivalve Anomalocardia brasiliana in beaches in the estuarine region of the semiarid in Rio Grande do Norte State, Barra and Pernambuquinho (04°56.978'S and 37°08.961'W and 04°56.792'S and 37°09.375'W, respectively). Samples were collected monthly during 37 months using five transects (300 m long and 400 m apart) laid perpendicularly to the beach line toward the sea. Seven collection points, 50 m apart, were set in each transect, and shellfish and sediment samples were collected. Temperature and salinity were measured in each transect. The results showed a temperature variation of average values ​​of 3 °C; the greatest variation (33.2 °C) was observed in May of 2009. The lowest average salinity values were observed between April and June of 2009 (5, 8.7, and 7.8, respectively). This fact was due to an atypical rainfall in the region, which resulted in a large freshwater inflow into the estuary; the average salinity values ​​were about 40 in the remaining months. The highest precipitation values were observed in April/09, April/10, and April/11; the highest precipitation occurred in April/09 (316.3 mm). The lower average densities of A. brasiliana were observed in April and May/09 when compared to the other months; the lowest value was observed in April/09 (26 ind/m2). The highest densities occurred between November/10 and July/11, with values ​​ranging from 70 to 322 ind/m2. The highest inflow of young individuals (lengths from 2 to 5 mm) was observed between April and June of 2010 and on September/10 while the highest frequency of adults (from 20 to 25 mm) occurred between December of 2010 and April of 2011. Hence, the results of this study show that in the months with the greatest rainfall, salinity and the average density of A. brasiliana showed the lowest values.

Resumo O objetivo do trabalho foi analisar a densidade e distribuição do bivalve Anomalocardia brasiliana em praias de uma região estuarina do semiárido do Rio Grande do N (Barra - 04°56,978'S, 37°08,961'O e Pernambuquinho - 04°56,792'S, 37°09,375'O). As coletas foram realizadas durante 37 meses (abril/09 a abril/12). Mensamente foram dispostos cinco transectos (300 m de comprimento e distanciando 400 m entre si, perpendicularmente à linha da praia em direção ao mar. Em cada transecto foram definidos sete pontos de coletas com distância de 50 m entre si e coletadas amostras de moluscos e sedimento. Em cada transecto aferiu-se a temperatura e salinidade da água. Os resultados mostraram que houve uma variação dos valores médios de temperatura de 3°C, sendo o mês de maio/09 ocorreu o maior valor dessa variável (33,2 °C). Quanto aos valores médios de salinidade, o período de abril a junho/09 apresentou-se os menores valores médio da salinidade (5, 8,7 e 7,8, respectivamente), tal fato ocorreu, devido a um período de chuvas atípicas na região, que resultou em um grande aporte de água doce no estuário, nos demais meses os valores médios da salinidade foram cerca de 40. Ao analisar a precipitação observou-se, que os maiores valores ocorreram nos meses de abril/09, abril/10 e abril/11, sendo que o maior valor da precipitação ocorreu no mês de abril/09 (316,3 mm). As densidades médias de A. brasiliana nos meses de abril e maio/09 foram menores quando comparadas as densidades médias dos demais meses, sendo que o menor valor foi observado no mês de abril/09 (26 ind/m2). As maiores densidades ocorreram no período de novembro/2010 a julho/2011, com valores variando de 70 a 322 ind/m2. No período de abril a junho de 2010 e no mês de setembro/10 foi observada uma maior entrada de indivíduos jovens (comprimentos entre 2 a 5 mm), enquanto que durante o período de dezembro/2010 a abril/2011 ocorreu uma maior frequência de indivíduos adultos (entre 20 a 25 mm). Assim verificou-se com o presente estudo que, nos meses que ocorreram maior precipitação, salinidade e densidade média de A. brasiliana foi menor.

Desempenho do polvo Octopus vulgaris alimentado com monodieta de mexilhão (Perna perna) / Performance of the Octopus vulgaris octopus fed on mussel (Perna perna) as monodiet

The octopus Octopus cf. vulgaris is a potential species to diversify aquaculture. Due to absence of balanced commercial diet, growth of the O. cf. vulgaris is based on natural diet with local and low-cost inputs. In Brazil, studies on experimental octopus ongrowing are recent and there is little available data. We evaluated the performance, survival and food consumption of O. vulgaris fed on mussel Perna perna for 20 days. Six octopuses with initial weight of 415±12.73g (mean±standard deviation) were divided into two groups (n=3 octopuses/group) according to the diet: MC Group (frozen mussels) and MV Group (live mussels). The Weight Gain of octopuses was 273.33±94.52g and 340.00±26.46g; the Absolute Growth Rate was 13.67±4.73 and 17.00±1.32g.dia-1 and the Specific Growth Rate of 2.95±0.58 and 2.64±0.37%.day-1 to MC and MV groups, respectively. There was no significant difference in performance between groups and the survival rate was 100%. Octopuses well accepted both diets and despite the amount of frozen mussels (129±31) was higher than in live mussels (100±19), there was no significant difference regarding the consumption between groups. Our results demonstrate that the mussel Perna perna can be used frozen or live as monodiet in O. cf. vulgaris ongrowing.(AU)

Population fluctuation and food preference of African snail by horticulture crops / Flutuação populacional e preferência alimentar do caramujo-africano por culturas hortícolas

The African snail Achatina fulica (Bowdich, 1822), originally from Africa, was introduced in Brazil and since then became an important pest, because of its resistance to abiotic conditions, hermaphroditism, polyphagia and absence of natural enemies. Considered as one of the 100 worst pests in the world, with the record of establishment in almost all Brazilian states, it causes sanitary, ecological and economic losses. In this context, the objective of this study was to determine the population dynamics and food preference of the giant snail in three areas of lettuce, located in Alagoas, Brazil. There was no statistical difference between food preference tests with and without choice among the varieties offered. To the fluctuation of the population of A. fulica, the Pearson correlation coefficients were negative only for temperature, and there was no correlation with precipitation and relative humidity.(AU)

O caramujo-africano Achatina fulica (Bowdich, 1822), originário da África, foi introduzido no Brasil e desde então se tornou uma praga importante, por sua resistência a condições abióticas, hermafroditismo, polifagia e ausência de inimigos naturais. Considerada uma das cem piores pragas do mundo, com registro de implantação em quase todos os estados brasileiros, causa perdas sanitárias, ecológicas e econômicas. Nesse contexto, o objetivo deste estudo foi determinar a dinâmica populacional e a preferência alimentar do caramujo-africano em três áreas de alface localizadas em Alagoas, Brasil. Não houve diferença estatística entre os testes de preferência alimentar com e sem escolha em meio às variedades oferecidas. Para a flutuação da população de A. fulica, os coeficientes de correlação de Pearson foram negativos apenas para a temperatura, não havendo correlação com a precipitação nem com a umidade relativa.(AU)

Determination of the antiangiogenic activity of Telescopium telescopium (Horn snail) extract using in ovo chorioallantoic membrane (CAM) assay

OBJECTIVE: To determine the antiangiogenic activity of Telescopium telescopium (Horn snail) extract using in ovo chorioallantoic membrane (CAM) assay.METHODS: Methanolic extract of Telescopium telescopium was subjected to modified Kupchan partitioning. Four treatment groups - negative control, positive control (quercetin), test samples, and blanks - were used for the in ovo chorioallantoic membrane (CAM) assay. ImageJ software was used to measure average vessel diameter (DV) and total length (LT) to determine the degree of vascularization, percent inhibition, and antiangiogenic activity. Biochemical screening was done for the crude extract and the fraction with the highest percent inhibition.RESULTS: Butanol fraction showed the highest percent inhibition in both average vessel diameter (DV) (417.30% ± 300.83) and total length (L T) (44.21% ± 8.11). There was no significant difference in the antiangiogenic activity of both crude and butanol fraction compared with quercetin. Biochemical screening confirmed the presence of sterols and carbohydrates in both fractions.CONCLUSION: Crude extract and butanol fraction resulted in positive percent inhibition values, indicating inhibition of angiogenesis. They were found to have no significant difference with quercetin in regard to their antiangiogenic activity. Sterols were assumed as the biochemical class of the antiangiogenic compound of interest.

Determination of the antiangiogenic activity of Telescopium telescopium (Horn snail) extract using in ovo chorioallantoic membrane (CAM) assay

Objective@#To determine the antiangiogenic activity of Telescopium telescopium (Horn snail) extract using in ovo chorioallantoic membrane (CAM) assay.@*Methods@#Methanolic extract of Telescopium telescopium was subjected to modified Kupchan partitioning. Four treatment groups – negative control, positive control (quercetin), test samples, and blanks – were used for the in ovo chorioallantoic membrane (CAM) assay. ImageJ software was used to measure average vessel diameter (DV) and total length (LT) to determine the degree of vascularization, percent inhibition, and antiangiogenic activity. Biochemical screening was done for the crude extract and the fraction with the highest percent inhibition.

Giant african snail, Achatina fulica (Férussac, 1821): an environmental and public health problem in the northwestern of Paraná State, Brazil / Caramujo africano, Achatina fulica (Férussac, 1821): um problema ambiental e de saúde pública no Noroeste do Paraná, Brasil

Achatina fulica, known as Giant African Snail (GAS), was introduced in Brazil as a substitute for the European escargot, Helix aspersa maxima. However, its cultivation was abandoned and the mollusk became an invasive species, found throughout Brazil and causing damage to health and the environment. In this context, this study analyzed the knowledge of the population about the damage caused by GAS, seeking to reveal a regional scenario on this issue. This exploratory and cross-sectional study was conducted by means of a questionnaire applied to 150 people, which obtained sociodemographic characteristics of respondents and specific responses about the knowledge and handling of GAS. The results showed that most of the respondents know the snail and are concerned about the transmission of diseases and losses in agricultural crops, but few recognize this pest as the basis of environmental imbalance. It is suggested to implement actions seeking the dissemination of such knowledge and the awareness of the population about the impact of this mollusk on the environment.

Achatina fulica, conhecida como caramujo gigante africano, foi introduzida no Brasil como um substituto do escargot europeu, Helix aspersa maxima. Contudo, seu cultivo foi abandonado e o molusco transformou-se numa espécie invasora, presente em todo o território brasileiro, provocando danos à saúde e ao meio ambiente. Assim, objetivou-se, com este trabalho, analisar o conhecimento da população sobre os danos causados pelo caramujo gigante africano, buscando evidenciar um cenário regional sobre esta problemática. A pesquisa teve caráter exploratório e transversal e foi realizada por meio da aplicação de um questionário para 150 pessoas, por meio do qual foram obtidas as características sociodemográficas dos respondentes e respostas específicas sobre o conhecimento e o manuseio do caramujo africano. Os resultados deste estudo mostraram que a maioria dos respondentes conhece o caramujo africano e se preocupa com a transmissão de doenças e com os prejuízos em culturas agrícolas, porém poucos reconhecem essa praga como base de desequilíbrios ambientais. Sugere-se que ações sejam implementadas, buscando a disseminação desses conhecimentos e a conscientização da população sobre o impacto desse molusco no meio ambiente.

Relaxing effect of eugenol and essential oils in Pomacea canaliculata / Efeito relaxante de eugenol e óleos essenciais em Pomacea canaliculata

ABSTRACT: This study evaluated the potential relaxing and/or molluscicidal effects of eugenol and essential oils of Origanum majorana, Ocimum americanum, Hesperozygis ringens, and Piper gaudichaudianum in the gastropod Pomacea canaliculata. Compounds were tested at concentrations of 100, 250, 500, and 750µL L-1 to evaluate the relaxing effects. In the second experiment, animals were exposed to 10, 25, and 50µL L-1 of essential oils of H. ringens and P. gaudichaudianum for a period of 24h for the evaluation of molluscicidal effects. Eugenol and essential oils of O. majorana and O. americanum showed relaxing effects at ≥250µL L-1, but the essential oils of H. ringens and P. gaudichaudianum did not promote relaxing or molluscicidal effects within the times and concentrations studied. Therefore, only eugenol and the essential oils of O. majorana and O. americanum can be used for relaxation purposes in P. canaliculata.

RESUMO: Este estudo teve como objetivo avaliar os possíveis efeitos relaxantes e/ou moluscicidas do eugenol e óleos essenciais de Origanum majorana, Ocimum americanum, Hesperozygis ringens e Piper gaudichaudianum no gastrópode Pomacea canaliculata. Os compostos foram testados nas concentrações de 100, 250, 500 e 750µL L-1 para avaliar os efeitos relaxantes. Em um segundo experimento, os animais foram expostos a 10, 25 e 50µL L-1 por 24 horas aos óleos essenciais de H. ringens e P. gaudichaudianum para avaliação dos efeitos moluscicida. O eugenol e os óleos essenciais de O. majorana e O. americanum apresentaram efeito relaxante nas concentrações ≥250µL L-1, mas os óleos essenciais de H. ringens e P. gaudichaudianum não promoveram efeito relaxante ou moluscicida no tempo e concentrações estudadas. Portanto, apenas o eugenol e os óleos essenciais de O. majorana e O. americanum podem serem usados para fins de relaxamento em P. canaliculata.

Distribution and density of the bivalve Anomalocardia brasiliana in the estuarine region of Northeastern Brazil

Abstract The objective of this study was to analyze the density and distribution of the bivalve Anomalocardia brasiliana in beaches in the estuarine region of the semiarid in Rio Grande do Norte State, Barra and Pernambuquinho (04°56.978S and 37°08.961W and 04°56.792S and 37°09.375W, respectively). Samples were collected monthly during 37 months using five transects (300 m long and 400 m apart) laid perpendicularly to the beach line toward the sea. Seven collection points, 50 m apart, were set in each transect, and shellfish and sediment samples were collected. Temperature and salinity were measured in each transect. The results showed a temperature variation of average values of 3 °C; the greatest variation (33.2 °C) was observed in May of 2009. The lowest average salinity values were observed between April and June of 2009 (5, 8.7, and 7.8, respectively). This fact was due to an atypical rainfall in the region, which resulted in a large freshwater inflow into the estuary; the average salinity values were about 40 in the remaining months. The highest precipitation values were observed in April/09, April/10, and April/11; the highest precipitation occurred in April/09 (316.3 mm). The lower average densities of A. brasiliana were observed in April and May/09 when compared to the other months; the lowest value was observed in April/09 (26 ind/m2). The highest densities occurred between November/10 and July/11, with values ranging from 70 to 322 ind/m2. The highest inflow of young individuals (lengths from 2 to 5 mm) was observed between April and June of 2010 and on September/10 while the highest frequency of adults (from 20 to 25 mm) occurred between December of 2010 and April of 2011. Hence, the results of this study show that in the months with the greatest rainfall, salinity and the average density of A. brasiliana showed the lowest values.

Resumo O objetivo do trabalho foi analisar a densidade e distribuição do bivalve Anomalocardia brasiliana em praias de uma região estuarina do semiárido do Rio Grande do N (Barra - 04°56,978S, 37°08,961O e Pernambuquinho - 04°56,792S, 37°09,375O). As coletas foram realizadas durante 37 meses (abril/09 a abril/12). Mensamente foram dispostos cinco transectos (300 m de comprimento e distanciando 400 m entre si, perpendicularmente à linha da praia em direção ao mar. Em cada transecto foram definidos sete pontos de coletas com distância de 50 m entre si e coletadas amostras de moluscos e sedimento. Em cada transecto aferiu-se a temperatura e salinidade da água. Os resultados mostraram que houve uma variação dos valores médios de temperatura de 3°C, sendo o mês de maio/09 ocorreu o maior valor dessa variável (33,2 °C). Quanto aos valores médios de salinidade, o período de abril a junho/09 apresentou-se os menores valores médio da salinidade (5, 8,7 e 7,8, respectivamente), tal fato ocorreu, devido a um período de chuvas atípicas na região, que resultou em um grande aporte de água doce no estuário, nos demais meses os valores médios da salinidade foram cerca de 40. Ao analisar a precipitação observou-se, que os maiores valores ocorreram nos meses de abril/09, abril/10 e abril/11, sendo que o maior valor da precipitação ocorreu no mês de abril/09 (316,3 mm). As densidades médias de A. brasiliana nos meses de abril e maio/09 foram menores quando comparadas as densidades médias dos demais meses, sendo que o menor valor foi observado no mês de abril/09 (26 ind/m2). As maiores densidades ocorreram no período de novembro/2010 a julho/2011, com valores variando de 70 a 322 ind/m2. No período de abril a junho de 2010 e no mês de setembro/10 foi observada uma maior entrada de indivíduos jovens (comprimentos entre 2 a 5 mm), enquanto que durante o período de dezembro/2010 a abril/2011 ocorreu uma maior frequência de indivíduos adultos (entre 20 a 25 mm). Assim verificou-se com o presente estudo que, nos meses que ocorreram maior precipitação, salinidade e densidade média de A. brasiliana foi menor.

Virulence genes in Escherichia coli isolates from commercialized saltwater mussels Mytella guyanensis (Lamarck, 1819)

Abstract The isolation of Escherichia coli from food is a major concern. Pathogenic strains of these bacteria cause diseases which range from diarrhea to hemolytic-uremic syndrome. Therefore the virulence genes in E. coli isolates from the mussel ( Mytella guyanensis) commercialized in Cachoeira, Bahia, Brazil were investigated. Samples were purchased from four vendors: two from supermarkets and two from fair outlets. They were conditioned into isothermal boxes with reusable ice and transported to the laboratory for analysis. E. coli strains were isolated in eosin methylene blue agar, preserved in brain-heart infusion medium with 15% glycerol and stored at -20 °C, after microbiological analysis. Virulence genes in the isolated strains were identified by specific primers, with Polymerase Chain Reaction. Twenty-four isolates were obtained, with a prevalence of elt gene, typical from enterotoxigenic infection, in 75% of the isolates. The stx and bfpA genes, prevalent in enterohemorragic and enteropathogenic E. coli, respectively, were not detected. The occurrence of elt virulence-related gene in the E. coli isolates of Mytella guyanensis reveals urgent improvement in food processing, including good handling practices, adequate storage and cooking before consumption, to ensure consumers health.

Resumo O isolamento de Escherichia coli a partir de alimentos é uma grande preocupação, pois cepas patogênicas desta bactéria podem causar desde diarreia até síndrome hemolítico-urêmica. Diante do exposto, o objetivo do trabalho foi pesquisar genes de virulência em isolados de Escherichia coli provenientes do sururu Mytella guyanensis comercializado na cidade de Cachoeira, Bahia, Brasil. As amostras foram adquiridas de quatro comerciantes, sendo duas de mercados e duas em pontos de venda na feira livre da cidade de Cachoeira, acondicionadas em caixas isotérmicas com gelo reutilizável e transportadas até o laboratório para a análise. Após a análise microbiológica, as cepas de Escherichia coli foram isoladas em ágar Eosina Azul de Metileno e preservadas em caldo Brian Heart Infusion e glicerol a 15% e mantidas a - 20° C. A identificação dos genes de virulência nas cepas isoladas foi realizada utilizando primers específicos, por meio da Reação em Cadeia da Polimerase. Foram obtidos 24 isolados de Escherichia coli, destes a prevalência do gene elt , característico de Escherichia coli enterotoxigênica, foi de 75% dos isolados. Não houve a detecção dos genes stx e bfpA nos isolados, os quais são prevalentes nas cepas de Escherichia coli enterohemorrágica e Escherichia coli enteropatogênica, respectivamente. A presença do gene elt relacionado à virulência de Escherichia coli nos isolados de Mytella guyanensis revela a necessidade da melhoria no processamento, incluindo boas práticas de manipulação, armazenamento adequado e cocção previa ao consumo, visando a garantia da saúde do consumidor.