ABSTRACT This study aimed to evaluate the yields of by-products and residues and the morphometry of juvenile tambaqui Colossoma macropomum undernutrition with different levels of lysine. Diets were elaborated containing 6.60, 9.72, 12.84, 15.96, 19.08, and 22.20 g kg−1 of total lysine, and these were fed to fish distributed in 18 tanks (310 L each one) for 90 days. Morphometric analysis, measurements of whole fish, by-products, and residues were taken and compared to each other. All variables were validated using ANOVA, Tukey's test, and quadratic regression analysis (P < 0.05). No differences were found for the morphometric variables (P > 0.05). The ratio between morphometric data for the standard and total length showed significance at levels of 9.72 and 15.96 g kg−1 (P = 0.03). The gutted fish and fillets, the protein and lipid contents of the fillets, and the weights and lengths of the intestines did not change (P > 0.05). Moisture was modified with lysine at levels of 22.20 g kg−1 (P = 0.00), and minerals, between 6.60 and 22.20 g kg−1 (P = 0.01). The increase in lysine levels in the diet led to an increase in fin weight (P = 0.00). It was concluded that the addition of lysine in the diet did not directly influence the morphometry and yields of the fish in the juvenile phase, but it did affect the fin waste and the skin by-product.

RESUMEN La determinación de valores hematológicos se ha utilizado para conocer las condiciones sanitarias de algunas especies animales. La tortuga cabezona del río Amazonas, Peltocephalus dumerilianus, se considera una de las especies de testudines menos conocidas en relación a su biología y estado de salud. Aquí, determinamos los parámetros bioquímicos hematológicos y plasmáticos de 17 adultos (ocho machos y nueve hembras) de P. dumerilianus con el fin de proporcionar valores de intervalo de referencia sobre los individuos clínicamente sanos. Recolectamos las muestras de sangre perforando la vena femoral con jeringas hipodérmicas largas heparinizadas. El dimorfismo sexual de los individuos se determinó mediante la observación externa de la forma del plastrón. Los valores medios obtenidos para los diez parámetros hematológicos y bioquímicos analizados fueron: recuento de glóbulos rojos = 0,32 millones μL-1; hematocrito = 20,6 %; hemoglobina = 8,5 g dL-1; volumen corpuscular medio = 681,6 fL; hemoglobina corpuscular media = 267,8 pg; concentración media de hemoglobina corpuscular = 41,9 g dL-1; glucosa = 80,6 mg dL-1, proteína total = 4,1 g dL-1, triglicéridos = 388,9 mg dL-1 y colesterol total = 79,3 mg dL-1. A pesar del dimorfismo sexual evidente para la especie, no hubo diferencia estadística significativa entre machos y hembras para los parámetros hematológicos y bioquímicos analizados aquí. Con base en estos resultados, la población se considera saludable y los valores de los parámetros coinciden con los rangos de referencia reportados previamente de las especies de testudines en la región. Los resultados obtenidos en este estudio pueden utilizarse en la evaluación del estado de salud de otras poblaciones de tortugas amazónicas, considerando especialmente aquellas acciones dirigidas al manejo, conservación y estrategias de cultivo de la especie.

ABSTRACT The determination of hematological values is used to obtain knowledge about the health conditions of animal species. The big-headed Amazon River turtles, (Peltocephalus dumerilianus) are considered one of the least known testudine species concerning their biology and health status. Herein, we determined the hematological and plasma biochemical parameters of17 (eight males and nine females) adult P. dumerilianus to provide reference interval values for clinically healthy individuals. We collected the blood samples by puncturing the femoral vein using long heparinized hypodermic syringes. Sexual dimorphism for individuals was determined by external observation of the shape of the plastron. The average values obtained for the ten hematological and biochemical parameters analyzed were red blood cell count = 0.32 million μL-1; hematocrit = 20.6 %; hemoglobin = 8.5 g dL-1; mean corpuscular volume = 681.6 fL; mean corpuscular hemoglobin = 267.8 pg; mean corpuscular hemoglobin concentration = 41.9 g dL-1; glucose = 80.6 mg dL-1, total protein = 4.1 g dL-1, triglycerides = 388.9 mg dL-1, and total cholesterol = 79.3 mg dL-1. Despite the sexual dimorphism evidenced for the species, there was no significant statistical difference between males and females for both hematological and biochemical parameters analyzed herein. Based on these results, the population is considered healthy, with parameter values coinciding with previously reported reference ranges for testudines species in the region. The results obtained in this study can be used for assessing the health status of other Amazonian turtle populations, especially in actions aimed at cultivation strategies, management, and species conservation.

ABSTRACT. The objective of the present study was to determine the apparent digestibility of juveniles of matrinxã Brycon amazonicus fed diets with different levels of protein. The experimental design was completely randomized, where the treatments consisted of four levels of protein in the diets (28, 32, 36 and 40%) and five replicates (water boxes) with 10 juveniles of matrinxã each. Diets were offered four times a day, and feces were collected twice a week, along 28 days, for digestibility analysis. Data collected were subjected to polynomial regression at 5% significance. Differences (p<0.05) were observed in dry matter digestibility, with higher digestibility according to increasing levels of protein in the diets. This behavior was directly expressed in the digestibility of nutrients by juveniles of matrinxã, such as % ash, % crude protein, apparent digestible energy, % digestibility of apparent digestible energy and energy: protein ratio. However, this was not observed (p > 0.05) in the digestibility of % ether extract. Digestibility of N, P, Ca, Mg, Cu and Zn presented linear positive (p < 0.05) behavior, in which the use of these minerals increased with the increase in the level of protein in the diets. However, the digestibility of K, Fe and Mn reduced (p < 0.05) with increasing protein levels in the diets. Thus, it can be concluded that the rise in protein level in diets for juveniles of matrinxã improves nutrient digestibility. The results of this study indicated that 40% crude protein in the diets provided better results.

Resumen: La piscicultura es una de las actividades zootécnicas que más ha crecido en los últimos años, en especial en la Amazonia brasileña. El presente estudio fue realizado en el área de cobertura del estado de Amazonas, uno de los mayores consumidores de pescado en Brasil, teniendo como objetivo caracterizar los sistemas de producción, el grado de severidad de impactos ambientales que esa actividad promueve y las diferentes perspectivas de desarrollo futuro en las distintas mesorregiones del estado. Las investigaciones se realizaron a través de la recolección de datos secundarios proporcionados por el Instituto de Protección Ambiental del Amazonas (IPAAM), que posee 1.382 pisciculturas registradas en su base de datos. Esta información fue organizada por microrregión (centro, suroeste, norte y sur) del estado, explorando sus principales indicadores técnicos, las infraestructuras de producción de formas jóvenes, el tamaño de los emprendimientos y el encuadramiento del grado de severidad de impacto ambiental por porte de la piscicultura . Los resultados obtenidos muestran que la piscicultura se practica mayoritariamente para el engorde de tambaqui con fines de comercialización, realizada en estructuras de tierra firme (viveros excavados y represas) en pequeñas áreas inundadas, con aplicación de sistema semi-intensivo de producción, siendo desarrollada cerca de (Manaus), teniendo como causa de su concentración factores logísticos y de infraestructura disponibles, con la mayoría de los emprendimientos encuadrados como bajo grado de severidad de impacto ambiental.

Abstract: Fish farming is one of the zootechnical activities that has grown the most in recent years, especially in the Brazilian Amazon. The present study was carried out in the area of the State of Amazonas, one of the largest consumers of fish in Brazil, aiming at characterizing the production systems, the degree of severity of environmental impacts that this activity promotes and the different perspectives of future development in the different mesoregions of the state. Te investigations were carried out through the collection of secondary data provided by the Institute of Environmental Protection of Amazonas (IPAAM), which has 1,382 fish farms registered in its database. Tis information was organized by the state's microregion (center, south-west, north and south), exploring its main technical indicators, production infrastructures of young forms, size of enterprises and the degree of severity of environmental impact by size of fish farming . Te results obtained show that fish farming is practiced mainly for fattening of tambaqui for commercial purposes, carried out in terra firme structures (excavated nurseries and dams) in small flooded areas, with application of semi-intensive production system, being developed near (Manaus), due to its concentration of available logistical and infrastructure factors, with most of the projects classified as low severity of environmental impact.

Resumo: A piscicultura é uma das atividades zootécnicas que mais tem crescido nos últimos anos, em especial na Amazónia Brasileira. O presente estudo foi realizado na área de abrangência do estado do Amazonas, um dos maiores consumidores de pescado no Brasil, tendo como objetivo caracterizar os sistemas de produção, o grau de severidade de impactos ambientais que essa atividade promove e as diferentes perspectivas de desenvolvimento futuro nas distintas mesorregiões do estado. As investigações foram realizadas por meio da coleta de dados secundários fornecidos pelo Instituto de Proteção Ambiental do Amazonas (IPAAM), que possui 1.382 pisciculturas registradas em seu banco de dados. Essas informações foram organizadas por microrregião (centro, sudoeste, norte e sul) do estado, explorando seus principais indicadores técnicos, as infraestruturas de produção de formas jovens, o tamanho dos empreendimentos e o enquadramento do grau de severidade de impacto ambiental por porte da piscicultura. Os resultados obtidos mostram que a piscicultura é praticada majoritariamente para engorda de tambaqui com finalidade de comercialização, realizada em estruturas de terra firme (viveiros escavados e barragens) em pequenas áreas alagadas, com aplicação de sistema semiintensivo de produção, sendo desenvolvida próximo a centro consumidor (Manaus), tendo como causa da sua concentração fatores logísticos e de infraestrutura disponíveis, com a maioria dos empreendimentos enquadrados como baixo grau de severidade de impacto ambiental.