From egg to slaughter: monitoring the welfare of Nile tilapia, Oreochromis niloticus, throughout their entire life cycle in aquaculture.

The primary aim of this study was to comprehensively evaluate the welfare of Nile tilapia (Oreochromis niloticus) throughout their entire life cycle within aquaculture, spanning from reproduction to slaughter. The methodology was structured to identify welfare indicators closely aligned with the principles of animal freedoms defined by the Farm Animal Council, encompassing environmental, health, nutritional, behavioral, and psychological freedom. Notably, psychological freedom was inherently considered within the behavioral and physical analyses of the animals. To accomplish this, an integrative systematic literature review was conducted to define precise indicators and their corresponding reference values for each stage of tilapia cultivation. These reference values were subsequently categorized using a scoring system that assessed the deviation of each indicator from established ideal (score 1), tolerable (score 2), and critical (score 3) ranges for the welfare of the target species. Subsequently, a laboratory experiment was executed to validate the pre-selected health indicators, specifically tailored for the early life stages of tilapia. This test facilitated an assessment of the applicability of these indicators under operational conditions. Building on the insights gained from this experimentation, partial welfare indices (PWIs) were computed for each assessed freedom, culminating in the derivation of a general welfare index (GWI). Mathematical equations were employed to calculate these indices, offering a quantitative and standardized measure of welfare. This approach equips tilapia farmers and processors with the tools necessary for the continuous monitoring and enhancement of their production systems and stimulate the adoption of more sustainable and ethical practices within the tilapia farming.

Non-Invasive Methods for Assessing the Welfare of Farmed White-Leg Shrimp (Penaeus vannamei).

Gradually, concern for the welfare of aquatic invertebrates produced on a commercial/industrial scale is crossing the boundaries of science and becoming a demand of other societal actors. The objective of this paper is to propose protocols for assessing the Penaeus vannamei welfare during the stages of reproduction, larval rearing, transport, and growing-out in earthen ponds and to discuss, based on a literature review, the processes and perspectives associated with the development and application of on-farm shrimp welfare protocols. Protocols were developed based on four of the five domains of animal welfare: nutrition, environment, health, and behaviour. The indicators related to the psychology domain were not considered a separate category, and the other proposed indicators indirectly assessed this domain. For each indicator, the corresponding reference values were defined based on literature and field experience, apart from the three possible scores related to animal experience on a continuum from positive (score 1) to very negative (score 3). It is very likely that non-invasive methods for measuring the farmed shrimp welfare, such as those proposed here, will become a standard tool for farms and laboratories and that it will become increasingly challenging to produce shrimp without considering their welfare throughout the production cycle.

Evaluation of methods for reducing epibionts during farming of the mangrove oyster Crassostrea gasar (Adanson, 1757).

Due to the competition for food, space, oxygen and due to their role as diseases vector, epibionts can negatively affect oyster farming. We assessed the efficacy of six methods commonly used for the removal of epibionts from oyster shells during farming. The experiment was conducted at an oyster farm on the Paraná coast - South Brazil. Oysters (Crassostrea gasar) were acclimated for 90 d in the cultivation system and later exposed to cleaning treatments: i) freshwater; ii) hypersaline water; iii) sodium hypochlorite solution; iv) quaternary ammonia solution; v) exposure to air; vi) hydroblasting; and vii) no cleaning procedure (control). After treatment, oysters were kept in the cultivation system for 15 and 30 d - when the total incrustation and mortality were measured. Epibionts from nine phyla were identified. The most abundant were Arthropoda (Crustacea) (62.5%), Mollusca (33.8%) and Annelida (3.1%). Freshwater [15 (n = 2263 epibionts) and 30 days (n = 2822 epibionts)] and hydroblasting [15 (n = 1850 epibionts) and 30 days (n = 2389 epibionts)] treatments were the most efficient to reduce epibionts and caused lower rates of oyster mortality [15 (5.0 and 3.33%, respectively) and 30 days (1.67 and 6.67%, respectively)].

Monitoring fish communities through environmental DNA metabarcoding in the fish pass system of the second largest hydropower plant in the world.

The Itaipu Hydroelectric Power Plant is the second largest in the world in power generation. The artificial barrier created by its dam imposes an obstacle for fish migration. Thus, in 2002, a fish pass system, named Piracema Channel, was built to allow fish to access areas upstream of the reservoir. We tested the potential of environmental DNA metabarcoding to monitor the impact of both the dam and associated fish pass system in the Paraná River fish communities and to compare it with traditional monitoring methods. Using a fragment of the 12S gene, we characterized richness and community composition based on amplicon sequence variants, operational taxonomic units, and zero-radius OTUs. We combined GenBank and in-house data for taxonomic assignment. We found that different bioinformatics approaches showed similar results. Also, we found a decrease in fish diversity from 2019 to 2020 probably due to the recent extreme drought experienced in southeastern Brazil. The highest alpha diversity was recorded in the mouth of the fish pass system, located in a protected valley with the highest environmental heterogeneity. Despite the clear indication that the reference databases need to be continuously improved, our results demonstrate the analytical efficiency of the metabarcoding to monitor fish species.

Metagenomic analysis of the bacterial microbiota associated with cultured oysters (Crassostrea sp.) in estuarine environments.

In this work, we identified the bacterial microbiota associated with farmed oystersin estuarine regions of four states in the north eastern region of Brazil. During the drought and rainy seasons, for eight months, twenty oysters were sampled seasonally from seven different marine farms. In the laboratory, DNA extraction, amplification, and sequencing of the 16S rRNA gene were performed to establish the taxonomic units. We identified 106 genera of bacteria belonging to 103 families, 70 orders, 39 classes, and 21 phyla. Out of the total, 40 of the genera represented bacteria potentially pathogenic to humans; of these, nine are known to cause foodborne diseases and six are potentially pathogenic to oysters. The most prevalent genera were Mycoplasma, Propionigenium, Psychrilyobacter, and Arcobacter. The results indicate the need for more systematic monitoring of bacteria of the genus Mycoplasma in oyster farming operations in the Brazilian north eastern region. Currently, Mycoplasma is not one of the microorganisms analysed and monitored by order of Brazilian legislation during the oyster production and/or commercialization process, even though this genus was the most prevalent at all sampling points and presents pathogenic potential both for oysters and for consumers.

Effects of salinity on the survival and histology of oysters crassostrea gasar (adanson, 1757) / Efeitos da salinidade na sobrevivência e histologia de ostras Crassostrea gasar (Adanson, 1757)

Water salinity is among the most important factors influencing the distribution, abundance, growth, and survival of Crassostrea gasar, an important aquaculture resource grown in estuarine environments in diverse regions of the world. The goal of the present work was to evaluate the effects of different salinities on survival and the tissues ofC. gasar under laboratory conditions. Two experiments were performed using adult oysters from five marine farms located in the bay of Guaratuba, Brazil. In Experiment 1, the daily survival rates were evaluated after the oysters were submitted to gradual acclimatization at salinities ranging from 0 to 65 gL-1 and maintained in the laboratory without feeding for up to 365 days. In Experiment 2, the oysters were exposed to salinity from 0 to 50 gL-1 for up to 30 days without feeding and possible histological alterations caused by salinity were assessed. Three tolerance ranges of C. gasar to salinity were identified: "Optimal" (between 4 and 40 gL-1), "Tolerable" (between 2.1 and 3.9 and between 41 and 50 gL-1) and "Intolerable" (less than 2 and greater than 50 gL-1). No evidence of histological alterations was observed in oysters exposed to the different salinities.

A salinidade da água está entre os fatores de maior influência na distribuição, abundância, crescimento e sobrevivência de Crassostrea gasar, um importante recurso aquícola cultivado em ambientes estuarinos em diversas regiões do mundo. O objetivo desse trabalho foi avaliar os efeitos da salinidade sobre a sobrevivência e nos tecidos de C. gasar exposta a diferentes salinidades, em condições laboratoriais. Foram realizados dois experimentos com ostras adultas provenientes de cinco fazendas marinhas localizadas na baía de Guaratuba, Brasil. No experimento 1, que foi realizado com o propósito de avaliar as taxas diárias de sobrevivência, as ostras foram submetidas à aclimatação gradual a salinidades variando de 0 a 65 gL-1 e mantidas em laboratório, sem alimentação, por até 365 dias. No experimento 2, as ostras foram expostas a salinidades de 0 a 50 gL-1 por até 30 dias, sem alimentação, para avaliação de possíveis alterações histológicas provocadas pela salinidade. Foram identificadas três faixas de tolerância de C. gasar à salinidade: Ótima (entre 4 e 40 gL-1), Tolerável (entre 2,1 e 3,9 e entre 41 e 50 gL-1) e Intolerável (menor que 2 e maior que 50 gL-1). Não foram encontradas evidências de alterações histológicas em função da exposição das ostras às diferentes salinidades.

Enlatamento do jundiá: caracterização centesimal, microbiológica e sensorial do produto final / Canning protocol of silver catfish and proximate, microbiological and sensorial characterization of the final product

This work aimed to develop the technical canning in order to increase the shelf life and aggregate value to the silver catfish and feature the final product by the chemical, microbiological and sensorial compositions. For the process, cans were sterilized at 120ºC during one hour and 20 minutes. The fisheries was cut and left in saturated brine for 10 min. The cover sauces were placed in cans at temperature of 80ºC. The physical and chemical compositions of the product were: moisture to Flitch in Tomato Sauce (JPT) 83.07%; Flitch in Vegetal Oil (JPO) 60.15%; Fillet in Tomato Sauce (JFT) 80.41% and Fillet in Vegetal Oil (JFO) 60.00%; protein: 4.73% for JPT; 17.89% for JPO; 5.24% for JFT and 16.54% for JFO; lipids: 7.47% for JPT; 24.17% for JPO; 11.07% for JFT and 25.47% for JFO; ash: 2.00% for JPT; 0.49% for JPO; 0.24% for JFT and 0.36% for JFO. For microbiological analysis, the results are presented within the standards required by the current legislation. The sensory analysis showed better acceptance for the JPT with average 7.83 (appearance), 7.73 (aroma), 7.73 (flavor), 7.60 (texture) and 7.67 (overall). The canning can offer one year of shelf life provided by the present experiment without compromising organoleptic and microbiological characteristics.(AU)

Este trabalho teve como objetivo desenvolver a técnica de enlatamento para aumentar o tempo de prateleira e agregar valor ao jundiá (Rhamdia quelen), além de caracterizar o produto final quanto à composição centesimal, microbiológica e sensorial. No processo, as latas foram esterilizadas a 120º C durante 1h 20 min. O pescado foi processando na forma de filé e posta e mantido em salmoura saturada durante 10 min. Os molhos de cobertura foram acondicionados à temperatura de 80ºC. Os valores de composição centesimal dos produtos foram: umidade: para a Posta em Molho com Tomates (JPT) 83,07%, Posta com Óleo Vegetal (JPO) 60,15%, Filé em Molho de Tomate (JFT) 80,41%, Filé em Óleo Vegetal (JFO) 60,00%; proteína bruta: JPT 4,73%, JPO 17,89%, JFT 5,24%, JFO 16,54%; lipídeos: JPT 7,47%, JPO 24,17%, JFT 11,07%, JFO 25,47%; e matéria mineral: JPT 2,00%, JPO 0,49%, JFT 0,24% e JFO 0,36%. Para análises microbiológicas, os resultados apresentam-se dentro dos padrões exigidos na legislação vigente. A análise sensorial demonstrou melhor aceitação para Posta em Molho com Tomates (JPT) com médias de 7,83 (aparência), 7,73 (aroma), 7,73 (sabor), 7,60 (textura) e 7,67 (impressão global). O enlatamento pode proporcionar um tempo de prateleira com validade de pelo menos 1 ano, como atestado pelo presente estudo, sem comprometer as características organolépticas e microbiológicas.(AU)

Enlatamento do jundiá: caracterização centesimal, microbiológica e sensorial do produto final / Canning protocol of silver catfish and proximate, microbiological and sensorial characterization of the final product

This work aimed to develop the technical canning in order to increase the shelf life and aggregate value to the silver catfish and feature the final product by the chemical, microbiological and sensorial compositions. For the process, cans were sterilized at 120ºC during one hour and 20 minutes. The fisheries was cut and left in saturated brine for 10 min. The cover sauces were placed in cans at temperature of 80ºC. The physical and chemical compositions of the product were: moisture to Flitch in Tomato Sauce (JPT) 83.07%; Flitch in Vegetal Oil (JPO) 60.15%; Fillet in Tomato Sauce (JFT) 80.41% and Fillet in Vegetal Oil (JFO) 60.00%; protein: 4.73% for JPT; 17.89% for JPO; 5.24% for JFT and 16.54% for JFO; lipids: 7.47% for JPT; 24.17% for JPO; 11.07% for JFT and 25.47% for JFO; ash: 2.00% for JPT; 0.49% for JPO; 0.24% for JFT and 0.36% for JFO. For microbiological analysis, the results are presented within the standards required by the current legislation. The sensory analysis showed better acceptance for the JPT with average 7.83 (appearance), 7.73 (aroma), 7.73 (flavor), 7.60 (texture) and 7.67 (overall). The canning can offer one year of shelf life provided by the present experiment without compromising organoleptic and microbiological characteristics.

Este trabalho teve como objetivo desenvolver a técnica de enlatamento para aumentar o tempo de prateleira e agregar valor ao jundiá (Rhamdia quelen), além de caracterizar o produto final quanto à composição centesimal, microbiológica e sensorial. No processo, as latas foram esterilizadas a 120º C durante 1h 20 min. O pescado foi processando na forma de filé e posta e mantido em salmoura saturada durante 10 min. Os molhos de cobertura foram acondicionados à temperatura de 80ºC. Os valores de composição centesimal dos produtos foram: umidade: para a Posta em Molho com Tomates (JPT) 83,07%, Posta com Óleo Vegetal (JPO) 60,15%, Filé em Molho de Tomate (JFT) 80,41%, Filé em Óleo Vegetal (JFO) 60,00%; proteína bruta: JPT 4,73%, JPO 17,89%, JFT 5,24%, JFO 16,54%; lipídeos: JPT 7,47%, JPO 24,17%, JFT 11,07%, JFO 25,47%; e matéria mineral: JPT 2,00%, JPO 0,49%, JFT 0,24% e JFO 0,36%. Para análises microbiológicas, os resultados apresentam-se dentro dos padrões exigidos na legislação vigente. A análise sensorial demonstrou melhor aceitação para Posta em Molho com Tomates (JPT) com médias de 7,83 (aparência), 7,73 (aroma), 7,73 (sabor), 7,60 (textura) e 7,67 (impressão global). O enlatamento pode proporcionar um tempo de prateleira com validade de pelo menos 1 ano, como atestado pelo presente estudo, sem comprometer as características organolépticas e microbiológicas.