Assessment of crabs Callinectes danae as definitive biomonitors of metal emissions

O presente estudo teve como objetivo desenvolver uma nova proposta de uso de um biomonitor na identificação de fontes emissoras de metais no meio ambiente. Foi selecionada a espécie de siri Callinectes danae como biomonitor e o estuário de Santos como área de estudo. Numa primeira etapa e considerando que o siri é um organismo bentônico, foi realizada uma avaliação preliminar do teor de metais no sedimento do estuário. Em seguida, foi realizada uma avaliação preliminar do teor de metais nos diferentes tecidos de indivíduos coletados na região (brânquias, hepatopâncreas e músculos). Baseado nos experimentos anteriores, foi proposto um modelo de distribuição dos metais entre os tecidos e destes em relação aos sedimentos. A validação deste modelo de distribuição (assinatura química) foi realizada por meio de um conjunto de procedimentos que visaram testar: 1) a robustez em função do tempo; 2) a especificidade para a região de estudo; 3) a sensibilidade às alterações dos níveis de metais em cada tecido. A partir deste modelo, foram identificados indícios para atribuição de fontes emissoras de metais. Desta forma, concluiu-se que, para a região do estuário de Santos, o siri da espécie C. danae pode ser utilizado como um biomonitor. O modelo proposto foi eficaz, uma vez que foi capaz de responder de forma conclusiva-positiva a todos os testes realizados na sua validação, confirmando esta espécie como um biomonitor definitivo para região. A robustez do modelo irá aumentar com novas coletas e a realimentação do banco de dados.This study aimed to develop a new methodology for the use of a biomonitor in the identification of metal discharges in environmental evaluations. Crabs of Callinectes danae species were used in an evaluation conducted in the Santos Estuarine System. In the first experiment and since C. danae is a benthic species, a preliminary assessment of the metal concentrations in sediment samples collected in the Santos Estuarine System was performed. Subsequently, a preliminary assessment of metal concentrations in the C. danae tissues was also peformed. The last experiment aimed to identify a chemical fingerprint for the Santos Estuarine System.The development of validation procedures for this model (chemical fingerprint) was conducted and aimed to test: 1) the stability of this model through time; 2) its local specificity for the Santos Estuarine System; 3) the sensibility of this model due to modifications in the metal concentrations in each tissue (gills, hepatopancreas and muscles). By the use of this model, it was possible to identify the sources of metal emissions. According to the results, C. danae can be used as a biomonitor for the Santos Estuarine System. The established model was able to responde in a positive-conclusive way to all the tests performed in its validation, confirming this species as a definitive biomonitor for this area. Thus, the stability of this model will increase with new sampling campaings and consequently introduction of new information in the database

Influence of the rearing system on phagocytic indexes and weight gain of the silver catfish (Rhamdia quelen, Quoy & Gaimard, 1824)

El consumo de pescado ha estado creciendo desde 1961. De hecho, el sector pesquero es esencial para prevenir el hambre y la desnutrición. Sin embargo, este sector tiene sus desafíos. Las poblaciones de peces se están agotando más allá de la sostenibilidad biológica, con enfermedades y riesgos de bioseguridad para la producción y daños al medio ambiente y los ecosistemas. Existe una clara necesidad de mejorar la piscicultura con la mínima ocupación e impacto ambiental. Los sistemas biofloc y acuapónicos se están utilizando y modificando para abordar estas necesidades. Sin embargo, los factores ambientales pueden afectar la inmunidad innata de los peces criados en estos sistemas. Comprender cómo estos sistemas afectan la inmunidad de los peces es fundamental para prevenir posibles peligros y fallas en estos métodos de producción. El objetivo de esta investigación fue evaluar el rendimiento, crecimiento e índices fagocíticos de juveniles de bagre (Rhamdia quelen) criados en sistemas de recirculación de agua, biofloc y acuaponía en consorcio con plántulas de berro (Nasturtium officinale). En cada sistema, 12 juveniles con un peso de 15,2 g±7,6 se dividieron aleatoriamente en tres repeticiones, alimentados con alimento comercial. Diariamente se evaluaron los siguientes parámetros físico-químicos: temperatura, amoníaco total y tóxico, nitrito y pH del agua. Los peces se pesaron mensualmente durante seis meses. Se observó que los juveniles de R. quelen criados en el sistema acuapónico alcanzaron un mayor peso promedio, pero no se detectó significancia estadística (p>0.05) en comparación con los criados en los sistemas de recirculación y biofloc. Al final del experimento, el índice fagocítico fue menor solo en el sistema de recirculación. La capacidad fagocítica fue menor en todos los sistemas. Aunque el sistema acuapónico presentó una baja ganancia de peso promedio/animal, el desempeño de este sistema fue efectivo en la reducción de las concentraciones de amoníaco total y nitrito en el agua, en consorcio con la producción de hortalizas.Fish consumption has been growing since 1961. Indeed, the fisheries sector is essential to prevent hunger and malnutrition. However, this sector has its challenges. Fish stocks are being depleted beyond biological sustainability, with diseases and biosecurity risks to production and harm to the environment and ecosystems. There is a clear need to improve fish farming with minimum occupation and environmental impact. Heterotrophic and aquaponics systems are being utilized and modified to address these needs. However, environmental factors can affect the innate immunity of fish raised in these systems. Understanding how these systems affect fish’s immunity is critical to prevent potential hazards and the breakdown of these production methods. The goal of this research was to evaluate the performance, growth, and phagocytic indexes of silver catfish (Rhamdia quelen) juveniles reared in water recirculation, biofloc, and aquaponics systems in consortium with watercress seedlings (Nasturtium officinale). In each system, 12 juveniles weighing 15.2 g±7,6 were randomly divided into three replicates, fed with commercial feed. The following physical-chemical parameters - temperature, total and toxic ammonia, nitrite, and water pH - were daily assessed. Fishes were weighed monthly for six months. It was observed that R. quelen juveniles reared in the aquaponic system achieved higher average weight, but no statistical significance was detected (p>0.05) when compared to those reared in the recirculated and biofloc systems. At the end of the experiment, the phagocytic index was lower only in the recirculating system. The phagocytic capacity was lower in all systems. Although the aquaponic system presented low average weight gain/animal the performance of this system was effective in reducing the concentrations of total ammonia and nitrite in the water, in consortium with the production of vegetables

Effect of dietary supplements in American bullfrogs reared in low and high stocking densities

The aim of this study was to evaluate the effect of the probiotic Bacillus subtillis and beta-glucan from the fungus Agaricus blazei on survival, growth and immunological capacity in bullfrogs (Lithobates catesbeianus) cultured in low and high stocking densities. Animals weighing 24.3 ± 2.38 g were randomly distributed into four treatments with four simultaneous replicates: D100: 100 frogs/m2 (control); D236: 236 frogs/m2; D236 + Prob.: 236 frogs/m2 supplemented with probiotic; and D236 + BG: 236 frogs/m2 supplemented with beta-glucan. The parameters evaluated were weight gain, survival, plasma corticosterone (CORT), phagocytic capacity (PC) and phagocytic index (PI), at 24 h and 15 and 30 days. There is significant interaction between treatments and time for CORT levels. At 30 days, these values were very close for the D100 (control) and D236 + BG groups. Meanwhile, no statistical differences were observed between treatments for PC and PI. These results indicate that beta-glucan reduced the effects of stress caused by high density in bullfrogs, but the probiotic did not reduce these effects. Both compounds are not efficient at increasing survival rates, weight gain and neither immune response of animals. Thus, the use of commercial food additives may not have the favorable impact desired by the farmer. Their use in aquaculture should be further studied in experiments involving a longer trial period and taking into account the cost of their use

Position paper sulle politiche per la cronicità e sugli interventi per la gestione dello scompenso cardiaco

The work represents a position paper on chronic diseases policies and management models. It is the result of a Consensus Conference with 14 stakeholders that took place between October and November 2018. After an analysis of chronic diseases policies in 10 Italian regions, the paper focuses on management models for one specific chronic disease, heart failure, around which the regional intervention has centred. This paper aims at: 1) ascertain the state of the art of Italian policies on chronic diseases by mapping regional plans, programs and projects; 2) understand the main trends affecting policies on chronic diseases and heart failure, through a compared analysis of the mapped legislation; 3) identify the characteristics of regional projects related to chronic disease management and, where available, to hearth failure management through the selection of those representing regional tendencies. Our findings show that chronic diseases are developing according to some trends including demand management, comorbidity and frailty management and management of service usage. The paper ends with 8 statements representing the point of view of the expert panel group who took part to the Consensus Conference