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The purpose of this paper was evaluate the palatability of the meat of tambaqui of different ages and environments, both from natural and cultivated systems. In order to carry out the consumers' acceptability test concerning the tambaqui meat from different feeding, 14 wild fish and 14 cultivated ones were used, with average weight ranging from 0.8 to 8.5 kg, already killed, cut and fresh. The samples were separated according to the environment (wild and cultivated), stored in thermal box and processed as standard fried ribs. The total of 200 untrained tasters of both genders was consulted, with the intention of finding the common public's opinion. The evaluated items were: flavor, color, smell and texture. The samples from pisciculture obtained better acceptability results regarding young fish's meat (63.5%), and the adult's (78.0%), as compared to the same age groups for the natural environment fish with 49.7% and 61.0% of the total evaluated, respectively. Thus, the sensorial analysis demonstrated a greater preference for cultivated tambaqui's meat, with emphasis on the items flavor and texture, which can be attributed to feeding quality (fish food with 28% of crude protein) and husbandry employed in the farming system

Armoured catfish Pterygoplichthys pardalis is an endemic fish from the Amazon basin (Brazil) and currently is the top ten target species in the regional fisheries. A total of 1200 samples were collected monthly from March 2011 to February 2012 with an average length of 28 ± 2.57 cm and average weight of 441.57 ± 103.37 g. The growth stock parameters for this species (Wt = 0.431227 * Lt2.08637; M = 0.93 year-1; F-Estimated = 0.91 year-1; F-10 = 3.02 year-1; A0.95 = 7.31 years; K = 0.41 year-1; Tr = Tc = 1.92 years; Lc = 21.14 cm; L∞= 38.85 cm; W∞ = 869.76 g) and exploitation rate (E-Estimated = 0.50; E-10= 0.80) reveal that its stocks are not being overfished in the study area. The baseline information obtained in this study can help support fisheries management strategies of P. pardalis, especially regarding the potential implementation of a policy to increase landings of individuals larger than 22.3 cm length. However, before making a final decision, it is necessary to carefully examine the available information and evidence aimed at sustainable fishing management and conservation of their stocks, which is of great cultural, social and economic importance for Amazonian peoples.

The demand for wild tambaqui has led to overfishing of their natural stocks, and has thus increased the demand for farmed fish. This has raised a question regarding the nutritional value of these groups of individuals; to see if they differ when they grow in wild and farmed environments. The meat of 28 tambaqui was evaluated by measuring the moisture, ash and total proteins among the fish from the two different environments in the states of Amazonas and Rondônia, Brazil. The averages of the centesimal composition showed significant differences, between environments and states. The moisture values of wild fish between the states did not differ, but were higher than those farmed in either of the states. The ash value also showed differences between groups by environment and between states. However, it was found that wild tambaqui from both states exhibited the best levels of protein and did not show statistical dissimilarities. The group farmed in Rondônia was also similar to the wild ones caught in that state. As for farmed fish, the averages between states were different, with the lowest value attributed to fish from Amazonas. The data show that wild tambaqui had a higher nutritional value than farmed fish.

The demand for healthy foods has also increased the demand for wild and farmed tambaqui since it is a fish rich in omega-3, -6 and -9. To determine which of the two types of fish has the best nutritional quality and thus test the hypothesis that there are no nutritional differences between the groups of fish evaluated, the method of ultraviolet absorption spectrophotometry was used. For this, tambaqui from different environments (wild and farmed) were obtained in the states of Amazonas and Rondonia, Brazil. The fish groups showed differences in the concentrations of omega-3, -6 and -9 (ANOVA, F (8.30) = 16.213, and p < 0.01), both between states and between environments. The wild fish of the Amazonas state presented the best quality meat, and exhibited the highest concentrations of omega-3 (0.223 g ± 0.05 g) and omega-9 (0.208 g ± 0.04 g), which also implies the presence of omega-6, while the other group of fish exhibited the lowest values of omega in their composition.