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Fish is the main source of food for the population of Tabatinga, who have six points of sale in the municipality. Describing the hygienic and sanitary conditions, fish quality and commercialized species were the objectives of this study. The “in loco” visits took place between August 2016 and July 2018 through observations and periodic surveys. Five orders, 17 families and 86 species traded in Tabatinga were identified. It was found that 67% are sold in natura, 29% cooled, 2% frozen, 1% dry salted and 1% salted. Basic structure such as isothermal boxes, utensils, chlorinated water and ice by traders is a problem in terms of hygiene and sanitation. In two places they have poor hygienic and sanitary conditions and there is no recommendation for buying fish, in two places they are public, and improvements were observed, but there is a need for handling training for traders, there is a private point with farmed fish and another without physical structure, but with the option of a new indigenous fair. The most suitable fish for consumption were found in vendors who store in isothermal boxes with ice in a 1:1 ratio, using water to clean the environment and utensils. We recommend not buying fish at ambient temperatures, exposed to dust, sun and close to streets. There is a need to guide consumers on the choice of quality fish for consumption. Complementary studies are needed for a microbiological and physicochemical evaluation to determine the quality of the fish. El pescado es la principal fuente de alimentación de la población de Tabatinga, quienes cuentan con seis puntos de en el municipio. Describir las condiciones higiénicas y sanitarias, la calidad del pescado y las especies comercializadas fueron los objetivos de este estudio. Las visitas “in loco” se realizaron entre agosto de 2016 y julio de 2018 a través de observaciones y relevamientos periódicos. Se identificaron cinco órdenes, 17 familias y 86 especies comercializadas en Tabatinga. Se encontró que el 67% se comercializan al natural, 29% refrigeradas, 2% congeladas, 1% saladas secas y 1% saladas. La estructura básica como cajas isotérmicas, utensilios, agua clorada y hielo por parte de los comerciantes es un problema en términos de higiene y saneamiento. En dos lugares tienen malas condiciones higiénicas y sanitarias y no hay recomendación para comprar pescado, en dos lugares son públicos y se observaron mejoras, pero se necesita capacitación en manejo a los comerciantes, hay un punto privado con pescado de piscifactoría y otra sin estructura física, pero con la opción de una nueva feria indígena. Los pescados más aptos para el consumo se encontraron en vendedores que almacenan en cajas isotérmicas con hielo en proporción 1:1, utilizando agua para limpiar el ambiente y los utensilios. Recomendamos no comprar pescado a temperatura ambiente, expuesto al polvo, al sol y cerca de la calle. Es necesario orientar a los consumidores sobre la elección de pescado de calidad para el consumo. Se necesitan estudios complementarios de evaluación microbiológica y fisicoquímica para determinar la calidad del pescado. O pescado é a principal fonte de alimento da população tabatinguense, comercializados em seis pontos no município. Descrever as condições higiênicas e sanitárias, qualidade do pescado e as espécies comercializadas foram os objetivos deste estudo. As visitas “in loco” ocorreram entre agosto de 2016 a julho de 2018 por meio de observações e levantamentos periódicos. Foram identificados 5 ordens, 17 famílias e 86 espécies comercializadas em Tabatinga. Verificou-se que 67% são comercializados de forma in natura, 29% resfriado, 2% congelado, 1% salgado seco e 1% salmorado. Estrutura básica como caixas isotérmicas, utensílios, água clorada e gelo pelos comerciantes é uma problemática quanto a higiene e sanitária. Em dois locais possuem péssimas condições higiênicas sanitárias e sem recomendação para compra de pescados, em dois locais são de poder público e foram observados melhorias, mas há necessidade de uma capacitação de manipulação aos comerciantes, há um ponto privado com peixes de cultivo e outro sem estrutura física, mas com opção de uma nova feira indígena. Os peixes mais adequados para consumos foram encontrados em vendedores que armazenam em caixas isotérmicas com gelo na proporção 1:1, com uso de água para limpeza do ambiente e utensílios. Recomendamos não comprar pescado em temperaturas ambiente, exposto a poeiras, sol e próximo de ruas. Há necessidade de orientar consumidores quanto a escolha de um pescado com qualidade para consumo. São necessários estudos complementares para uma avaliação microbiológica e físico-química para determinar a qualidade do pescado.

This study evaluated the impact of transporting Nile tilapia at stocking densities of 250 kg/m³ and 500 kg/m³ for 1 h, with post-transport resting periods of 0, 2, 4, and 6 h, on biochemical parameters and fillet quality. A 2 × 4 factorial design was employed for the experiment, with 15 repetitions per treatment. The density of 500 kg/m³ resulted in a longer time to rigor mortis after 4 h of rest, while shorter rigor times were observed at 0 and 2 h. Fillets taken from fish transported at 250 kg/m³ for 4 h exhibited greater intensities of red and yellow color. The highest weight loss during cooking occurred in fish transported at 500 kg/m³ without rest. High-density stocking increased the pH of the fillets, reduced color intensity, and increased weight loss and drip loss. Resting periods of 4 and 6 h resulted in firmer fillets with improved water retention. Fish rested for 6 h at 250 kg/m³ recovered glycogen and glucose levels, indicating restored homeostasis. In contrast, fish subjected to high-density transport showed impaired metabolic recovery and compromised fillet quality. These results support the use of resting periods to improve fish welfare and product quality in aquaculture systems.

The objective of the work was to evaluate the effects of adding lemongrass essential oil on growth and oxidative stress in the rearing phase of Oreochromis niloticus. Two hundred Nile tilapia fingerlings (0.974±0.007g) were used, at a density of 10 fish per aquarium (70 L). The treatments consisted of five levels of lemongrass essential oil (EO) (0.00; 0.89; 1.78; 2.67; and 3.56mg kg-1) added to the feed, with four replicates. The animals were fed ad libitum, four times a day, for 37 days, at low temperatures. At the end of the experiment, the fish were anesthetized, weighed, euthanized, and dissected to obtain vicerosomatic and hepatosomatic index parameters. Liver samples from five animals from each experimental unit were collected for biochemical analysis of lipoperoxidation, catalase, glutathione S-transferase, superoxide dismutase, and protein carbonylation. The feeding with lemongrass essential oil influenced fish survival, and the other productive performance parameters did not show significant differences. At redox equilibrium, a decrease in glutathione S-transferase and increased superoxide dismutase activity were observed. It is concluded that the addition of up to 3.56mg kg-1 of lemongrass EO does not interfere with the productive performance improves survival and influences the redox balance of the animals.

Different anesthetic agents are commonly used during procedures performed in aquaculture to minimize stress and maximize fish welfare during handling. A Kinguio fish was treated with a history of a mass near the left eye. In the clinical evaluation, a pedunculated neoformation was found in the periocular region. The fish was submitted to anesthesia for surgical removal of the mass, which was later referred to histopathological evaluation, revealing myxoma. The anesthesia protocol used 1% propofol at a concentration of 5 mg/liter of water and morphine at a dose of 5 mg/kg, intramuscularly. Immediately after the end of the procedure, the fish was returned to the aquarium and its anesthetic recovery was observed. The objective of this report is to describe a surgical procedure in kinguio fish and to determine the efficacy of propofol associated with morphine in this species. As a result, complete immobilization of the fish was obtained with propofol, reaching the fourth stage of anesthesia and the administration of morphine suggested being able to provide effective and long-lasting analgesia. It is concluded that despite the positive results obtained, anesthesia in fish still needs to be extensively investigated to refine analgesia protocols during procedures that cause pain and stress.

The study’s aim was to evaluate the sperm movement in the semen of Rhamdia quelen, cryopreserved at different times of exposure to nitrogen vapor, besides different equilibration times and with different concentrations of methanol, and in thawed semen kept at 25ºC for different periods of time. Three distinct experiments were carried out. In the first experiment, fresh semen aliquots were diluted in a solution containing 5% D-Fructose, 5% milk powder (Nestle®, Ninho Fortificado®) and 10% methanol, filled into 0.25 mL straws and immediately kept in nitrogen vapor by 0,5; 1.0; 4.0; 8.0; 12.0 and 18.0h. After these times, the straws were transferred to the liquid nitrogen (-196°C). After 72 h, the semen was thawed by immersing the straws in water at (25 ° C) for 10 seconds. The sperm activation was evaluated by diluting the thawed semen in distilled water in the proportion of 1:250 (semen:activating solution; v/v). Motility and spermatic velocity in thawed semen were measured using the CASA system. In the second experiment, the fresh semen was diluted in solutions with glucose and powdered milk (Nestle®, Ninho Fortificado®) and 5.0; 7.5; 10.0; 12.5% methanol. Immediately after, it was filled into 0.25mL straws and kept at 25ºC by equilibrium times corresponding to 0, 20, 40 and 60 minutes. Subsequently, part of the straws was used for spermatic evaluation before cryopreservation and others were submitted to cryopreservation in nitrogen vapor for 30 minutes and after transferred to liquid nitrogen (-196°C). The processes of thawing and sperm evaluation were performed as described above. In the third experiment, the cryopreserved semen was thawed and kept at 25°C for 0.0; 7,5; 15,0; 22.5 and 30.0 minutes. After each time, the spermatic movement was evaluated as described above. The exposure time of straws to nitrogen vapor and the kept time of the thawed semen at 25ºC did not affect (p > 0.05) the sperm movement. On the other hand, methanol concentrations and equilibrium time (p < 0.05) influenced the spermatic movement interactively both, before and after cryopreservation. The best results were achieved when the semen was cryopreserved immediately after dilution. The cryopreservation of Rhamdia quelen semen can be successfully performed when the semen is diluted in a solution containing 5% D-Fructose, 5% milk powder and 11.66% of methanol and immediately filled into 0.25 mL straws and kept in nitrogen vapor by 30 min before being transferred to liquid nitrogen. In addition, after thawing, the semen can be kept at 25ºC for up to 30 minutes without damage to spermatic movement.