Fillet Composition Research Articles

Performance of poly cultured fish species fed organic or commercial diets

Para a produção de peixes orgânicos o sistema de policultivo é indicado. O objetivo deste estudo foi verificar o desempenho de peixes criados em sistema de policultivo, alimentados com dieta orgânica ou comercial, em experimento de campo realizado no sul do Brasil. O policultivo compreendeu a combinação de espécies com diferentes hábitos alimentares: Rhamdia quelen (30%), Cyprinus carpio (20%), Pterygoplichthys joselimaianus (15%), Prochilodus lineatus (15%) Hypophthalmichthys molitrix (7,5%), H. nobilis (7,5%) e Ctenopharyngodon idella (5%), distribuídas (1,5 peixe m-2) em viveiros escavados de quatro propriedades rurais, em delineamento em blocos casualizados. Foram avaliados dois tratamentos alimentares, dieta orgânica artesanal peletizada e dieta convencional comercial extrusada, ao longo de 12 meses. Ao final do período de cultivo sobrevivência média, peso médio final, taxa de crescimento específico e composição do filé não diferiram entre os tratamentos dietéticos. Todavia, foi obtida produtividade média significativamente maior nos viveiros em que os peixes foram alimentados com a dieta orgânica (4.877,8kg ha-1) em comparação aos que receberam a dieta comercial (3.067,1 kg ha-1). Conclui-se que a suplementação alimentar com dietas orgânicas peletizadas registrou maior produção do que dieta comercial neste sistema de policultivo. Esperamos que estes resultados estimulem mais pesquisas sobre a piscicultura orgânica.

Changes in food quality and microbial composition of Russian sturgeon (Acipenser gueldenstaedti) fillets treated with low temperature vacuum heating method during storage at 4 °C

Russian sturgeon is a high-quality cultured fish and traditional heating methods may lead to deterioration of its food quality. This study aimed to evaluate the food quality and microbial composition of sturgeon fillets by low temperature vacuum heating (LTVH) and storage at 4 °C. The treatments varied in temperature (50, 60, and 70 °C) and duration (15 and 30 min); samples treated by traditional heating (100 °C, 15 min) methods were included as controls. We found that LTVH could reduce the values of lightness (L*), yellowness (b*), and pH and increase the values of redness (a*), chewiness, and hardness, to promote food quality. The biogenic amine content declined with the increase in heating temperature and time, the histamine of most concern was low at the end of storage, the values of LTVH70-30 and TC was 33.12 ± 1.25 and 30.39 ± 0.86 mg/kg. The total viable count (TVC) and biogenic amines showed the same trend, and the finial TVC values of LTVH60-30, LTVH70-15, LTVH70-30 and TC were 6.72 ± 0.17, 6.33 ± 0.18, 6.18 ± 0.08 and 5.93 ± 0.16 log CFU/g, which did not exceed the limit value (7 log CFU/g), indicating that the biosafety risk was reduced. According to the high-throughput sequencing results, the microbial composition of LTVH samples showed a lesser abundance pseudomonads than that found in the control. Thus, LTVH technology could be used as an alternative to traditional heating treatment.

Proximal composition and fatty acid profile of fresh and smoked fillets of Pangasius hypophthalmus

The aim of this study was to determine the proximal composition and the fatty acid profile of fresh and smoked fillets of Pangasius hypophthalmus. After brining (4% / 270 min), the salted fillets of Pangasius hypophthalmus were pre-dried at 30 °C for 30 min, then smoked at 30 °C / 120 min; 50 °C/ 240 min and at 80 °C for 240 min. The proximal composition was determined using standard methods and the fatty acid profile was analyzed by GC / MS. The mean water, protein, ash and lipid content of the fresh fillet was 77.32 ± 2.15; 19.66 ± 0.46; 1.24 ± 0.14; and 1.00 ± 0.02% (wet basis), respectively. Smoking had a significant influence (P ˂ 0.05) on the proximal composition, particularly on the protein (28.74 ± 0.25%) and ash (3.94 ± 0.08%) content. After smoking, no significant change (P ˃ 0.05) was observed in the proportion of monounsaturated fatty acids in fish, but the proportions of polyunsaturated fatty acids and saturated fatty acids increased significantly in the smoked fillet compared with the fresh filet. The proportions of fatty acid ω-6 and ω-3 and the ratio ω-6 / ω-3 of fresh fillets of Pangasius hypophthalmus were 33.23, 4.79 and 6.94, respectively; while for smoked fillets the values were 38.40, 5.45 and 7.05, respectively. This study suggests that smoking improves the nutritional value of Pangasius hypophthalmus because of its high protein and PUFA content known for its beneficial health effects.

RENDIMENTO E COMPOSIÇÃO CENTESIMAL DE FILÉS E CARNE MECANICAMENTE SEPARADA DE SARAMUNETES (Pseudupeneus maculatus BLOCH, 1793)

O objetivo do estudo foi avaliar o rendimento e a composição centesimal de filés de saramunetes (Pseudupeneus maculatus) e da carne mecanicamente separada (CMS) sem lavar, com uma e duas lavagens com água. Os saramunetes apresentaram rendimento de filés ligeiramente inferior quando comparados com outros peixes. Por outro lado, o rendimento da CMS foi próximo ao observado em outros peixes comerciais. A umidade das CMS foi maior (P < 0,05) que a dos filés, sendo que o aumento do número de lavagens daCMS causou aumento da umidade. Os filés apresentaram alto teor proteico, superior (P < 0,05) ao da CMS, e baixa porcentagem de lipídeos. A CMS apresentou porcentagem de lipídeos superior à dos filés, e o aumento do número de lavagens da CMS causou diminuição (P < 0,05) na porcentagem de lipídeos. A porcentagem de cinzas da CMS foi superior à dos filés e houve também diminuição (P < 0,05) após a lavagem. A composiçãocentesimal da CMS sem lavar foi próxima à do filé. Portanto, recomenda-se a não lavagem da CMS de saramunetes para evitar perdas de compostos nutricionais (proteína, lipídeos e cinzas) e a formação de resíduos líquidos.

Effects of long‐term restricted feeding followed by full feeding on growth, processing yield, fillet proximate composition, and economics of market‐size hybrid catfish, ♀ Ictalurus punctatus × ♂ Ictalurus furcatus

AbstractA pond study examined the effects of long‐term restricted feeding followed by full feeding on production and processing characteristics, fillet composition, and economics of market‐size hybrid catfish, ♀ Ictalurus punctatus × ♂ Ictalurus furcatus. Market‐size fish averaging 674 g were stocked into 24 ponds (0.04 ha) at 17,300 fish/ha. Fish were either fed once or twice weekly for 4 months or once or twice weekly for 4 months followed by 15‐ or 30‐day daily full feeding. All fish were fed to apparent satiation on days fed. Fish fed once weekly for 4 months gained about 30% weight and those fed twice weekly gained 70% weight. Feeding once or twice weekly for 4 months followed by 15‐ or 30‐day full feeding did not significantly affect carcass yield compared with the initial sample (overwintered fish). At least 30 days of full feeding were needed to restore fillet yield to normal levels. Based on economic analysis and processing yield, it is suggested fish fed once weekly should be given full feed for 15 days or so to improve fillet yield before harvest. Fish fed twice weekly can be harvested with or without 15 days full feeding.

Influence of temperature on growth, feed consumption and chemical composition in the muscle of PacuPiaractus mesopotamicus

The zootechnical performance of fish can be influenced by temperature through the induction of metabolic changes that are likely to affect growth and body composition. Thus, the objectives of this study were: (a) to examine the influence of five different temperatures (18, 21, 24, 27 and 30°C) on growth performance and metabolic parameters and (b) to evaluate the relationship of the protein efficiency ratio (PER) with the fillet proximate composition of Pacu juveniles. Growth and feed consumption (FC) were positively correlated with temperature (R2 = .95), while PER and FC were negatively correlated with temperature (R2 = .89). For the fillet composition, ethereal extract increased, and moisture decreased with the temperature. Protein content was lowest at 18 and 30°C and highest at 21, 24 and 27°C. The robust adjusted curve between PER and fillet protein content in relation to temperature showed the best result at 21°C. The obtained results indicate that Pacu juveniles reared between 21 and 27°C showed better protein efficiency with regard to FC, and this effect reflected better meat quality.

Nutritional and Growth Effect of Insect Meal Inclusion on Seabass (Dicentrarchuss labrax) Feeds

Abajo: se repite los tres en el resumen. This work studies the effect of high-level fish meal replacement with insect meal: YW meal (obtained from Tenebrio larvae fed a broiler diet), BSF meal (from hermetia larvae fed broilers diet), BSFm meal (obtained from hermetia larvae fed discard fish) on growth performance nutritive indices and in vitro digestibility of Dicentrarchus labrax juvenile. Three different insect meals were used: BSF meal from hermetia larvae fed broilers diet; BSF improve (BSFm) obtained from hermetia larvae fed discarded fish; YW meal obtained from the larvae of Tenebrio fed a broiler diet. Five diets were used, a control (C) diet and four experimental diets by replacing fishmeal with insect meal from BSF at 30% and 50% (BSF30 and BSF50) substitutions, BSFm at 50% substitution (BSF50 m) and YM at 50% substitution (YW50). Nutritional and growth indices worsened by including insect meal, especially for hermetia meal at 50% substitution, BSF50 and BSF50 m. The internal organs’ weight reflected the growth of the fish fed each experimental diet. No differences were found in fillet composition. Nevertheless, under our experimental condition, YW replacement obtained better results than both BSF diets.

Improvement of lipid quality on nile tilapia fillet composition with low protein feeding treatment

The lipid composition is directly related to nutritious significance of fish meat. In this paper we evaluate the possibility of tuning lipid composition of Nile Tilapia fillet changing the feeding treatments with different levels of energy and protein using lipidomic approach. Five feeding treatments were used varying protein and energy content with soy protein, corn carbohydrates and soy oil. Easy Ambient Sonic-Spray Ionization mass spectrometry in negative mode was used for lipidomic characterization of polar lipids in Nile Tilapia fillet, that were extracted using the Bligh & Dyer method and evaluated by principal component analyzes revealing differences over the treatments. High Resolution Mass Spectrometry data obtained were imported into Lipid Maps (www.lipidmaps.org, accessed on 10/19/2018) for molecular identification. The major influence to separate the treatments was protein content, energy does not appear to differentiate the groups. Thirteen different ions were observed as the major differentiators of the groups and nine compounds were identified comparing the mass spectrometric results to Lipidomic library, and they are related to high metabolic activity, lipids with anti-diabetic effect, and fat levels reducers.

PRODUCTION OF TILAPIA IN BIOFLOC WITH DIFFERENT SALT CONDICTIONS: AN EVALUATION OF BODY COMPOSITION AND ORGANOLEPTIC PROPERTIES

Biofloc systems for aquaculture production are excellent options to attend the increasing demand for fish. Despite the advantages, these systems lead to accumulation of nitrogenous residues that need to be avoided, which can be achieved by the addition of salts to the water. However, salts may interfere with the body composition and the organoleptic properties of fish. Therefore, we evaluate the body composition and acceptability of tilapia fillets produced under different salt conditions. Body composition was measured by moisture, ethereal extract, crude protein and minerals, and tested by Permutational Multivariate Analysis of Variance (PERMANOVA). To infer on acceptability, a sensorial analysis was performed to produce preference scales of aroma, appearance, texture, flavor and off-flavor attributes. These were summarized with Principal Coordinates Analysis and tested by PERMANOVA. The body composition shows no significance difference between salts conditions. However, the organoleptic properties according to the participants were peculiar and showed lower influence of the salt condition. In the order of preference, the most accepted fish was cultivated in a conventional system (ponds without salinity). Therefore, salt conditions in biofloc systems did not significantly change the body composition of the fish, but subtle reduced their acceptability.

COLD AND HOT SMOKED NILE TILAPIA FILLETS: QUALITY AND YIELD OF PIGMENTED AND UNPIGMENTED FILLETS

Aiming evaluate the effects of smoking techniques on the quality of tilapia fillets, a 2x2 factorial scheme experiment was conducted comprising two smoking techniques (hot and cold) and two pigmentation (with and without). Cold smoked fillets and fillets with pigmentation demonstrated a greater yield. Hot smoked fillets were tenderer and presented lower moisture and greater ash and protein contents. The pigmentation did not influence the smoked fillet composition, but ash content was greater in fillets without pigmentation. The sensory acceptance of hot smoked fillets was better. The pigmentation influenced the color and appearance; however, fillets without pigmentation gave better flavor.

Diets supplemented with Saccharina latissima influence the expression of genes related to lipid metabolism and oxidative stress modulating rainbow trout (Oncorhynchus mykiss) fillet composition

This study aimed to evaluate the impact of diets including increasing amounts (1, 2 and 4%) of an iodine-rich macroalgae, Saccharina latissima, on gene expression and fillet composition of commercial-sized rainbow trout. Liver and muscle expression of genes related to growth, iodine, oxidative stress, and lipid metabolism, and the fillet content of fatty acids, cholesterol, and vitamin D3 were assessed. The highest kelp inclusion led to lower final body weight and HSI, without significant differences in mRNA transcription of genes involved in growth (ghr1, ghr2 and igf1) or iodine metabolism (dio1, thra, and thrb). A significant downregulation of an oxidative stress marker, gpx1b2, was observed in fish fed 2% S. latissima, which might suggest the need for less endogenous antioxidants. Dietary inclusion of kelp impacted lipid metabolism, with a downregulation of fatty acid synthase, accompanied by a general decrease of fatty acids in fillet. The present study demonstrated that supplementation of diets with 1 or 2% S. latissima can be achieved without detrimental effects on rainbow trout final weight. Evidence suggest a lipid-lowering effect of diets that did not compromise fillet EPA and DHA concentrations, being 3.7 times above the recommended levels for human consumption.

Co-culture of Nile tilapia (Oreochromis niloticus) and red seaweed (Gracilaria tenuistipitata) under different feeding rates: effects on water quality, fish growth and feed efficiency

Nile tilapia, Oreochromis niloticus (4.12 ± 0.05 g initial weight), and red seaweed, Gracilaria tenuistipitata, were co-cultured in 250-L tanks for 8 weeks. Six feeding treatments were conducted, with the control group (monoculture) being fed a commercial pellet (30% protein, 6% lipid) at 100% feed ration (4% of biomass per day), while fish in the five other groups were co-cultured with red seaweed (1 kg m−3) and received pellet at 80%, 60%, 40%, 20%, and 0% of the feeding ration of the control. The results indicated that the concentrations of TAN, NO2−, NO3−, and PO43− in the co-culture tanks were much lower than those in the monoculture. Moreover, the growth rate and productivity of fish in the 80% feeding ration treatment were comparable to those in the control group (p > 0.05). However, fish performance gradually reduced with a decrease in feeding rates from 60% downwards and all were significantly inferior to the control group (p < 0.05). Feed conversion ratio and feed cost were lower at the lower feeding rates. The results also proved that the co-culture of tilapia–red seaweed supplied at 80% feed ration, which could reduce feed cost by 28.9% compared with the control, still sustained normal growth while also maintaining better water quality. The proximate composition of fish fillet (moisture, protein, lipid, and ash) is also discussed.

Antioxidant Effect of Nanoemulsions Based on Citrus Peel Essential Oils: Prevention of Lipid Oxidation in Trout

AbstractThe antioxidant effects of oil‐in‐water nanoemulsion based on edible citrus peel essential oils on the fatty acid composition of rainbow trout fillets stored at 4 ± 2 °C are investigated. Fish fillets are treated with nanoemulsion and stored for 16 days. Lipid samples are converted into fatty acid methyl esters which are then detected by gas chromatagrophy (GC). The results show that palmitic acid (C16:0), palmitoleic acid (C16:1), stearic acid (C18:0), vaccenic acid (C18:1ɷ‐7), oleic acid (C18:1ɷ9), eicosenoic acid (C20:1ɷ9), linoleic acid (C18:2ɷ6), linolenic acid (C18:3ɷ3), eicosapentaenoic acid (EPA) (C20:5ɷ3), and docosahexaenoic acid (DHA) (C22:6ɷ3) are the most important fatty acids in fish meat. While polyene index and hypocholesterolemic:hypercholesterolaemic fatty acid ratios decrease in trout fillets during cold storage, thrombogenicity index and atherogenicity index generally increase (especially in control and Tween 80 groups). The concentrations of monounsaturated fatty acids (MUFAs) and polyunsaturated fatty acids (PUFAs) are higher in the treatment groups and the saturated fatty acids (SFAs) are lower in all groups compared to those of the control group. Application of nanoemulsion based on citrus essential oils prevents oxidation of PUFA especially EPA and DHA, thus has potential as a preservative for fish oil.Practical Applications: In recent years, nanotechnological applications have been increasingly applied to the protection of food. Similarly, natural essential oils are used to increase the shelf life of foods. This study demonstrates the combined effect of a new method of nanoemulsions and essential oils on the safety of foods.

Short-Term Responses to Fatty Acids on Lipid Metabolism and Adipogenesis in Rainbow Trout (Oncorhynchus mykiss).

Fish are rich in n-3 long-chain polyunsaturated fatty acids (LC-PUFA) such as eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids. Due to the increasing use of vegetable oils (VO), their proportion in diets has lowered, affecting lipid metabolism and fillet composition. Rainbow trout cultured preadipocytes were treated with representative FA found in fish oils (EPA and DHA) or VO (linoleic, LA and alpha-linolenic, ALA acids), while EPA and LA were also orally administered, to evaluate their effects on adipogenesis and lipid metabolism. In vitro, all FA increased lipid internalization, with ALA producing the highest effect, together with upregulating the FA transporter fatp1. In vivo, EPA or LA increased peroxisome proliferator-activated receptors ppara and pparb transcripts abundance in adipose tissue, suggesting elevated β-oxidation, contrary to the results obtained in liver. Furthermore, the increased expression of FA synthase (fas) and the FA translocase/cluster of differentiation (cd36) in adipose tissue indicated an enhanced uptake of lipids and lipogenesis de novo, whereas stable or low hepatic expression of genes involved in lipid transport and turnover was found. Thus, fish showed a similar tissue metabolic response to the short-term availability of EPA or LA in vivo, while in vitro VO-derived FA demonstrated greater potential inducing fat accumulation.

Dietary lipid level and source affect metabolic responses in hybrid catfish (Pseudoplatystoma reticulatum × Leiarius marmoratus)

This study was undertaken to evaluate the effect of dietary lipid source [linseed oil (LO, rich in 18:3 n−3); corn oil (CO, rich in 18:2 n−6); olive oil (OO, rich in 18:1n−9); and fish oil (FO, rich in LC-PUFA)] and level (9% L and 18% L) on growth, body composition and selected plasma biochemistry parameters in hybrid catfish (Pseudoplatystoma reticulatum × Leiarius marmoratus) juveniles. Moreover, liver histology (lipids, glycogen, cell vacuolization) and key metabolic enzyme activities were also evaluated. After 8 weeks of feeding, there were no differences in growth performance and whole-body composition between groups. Plasma lipoprotein, muscle and liver composition, and G6PD and ME activity were affected by lipid level and source. No differences were observed between groups in hepatic ALT activity; however, AST activity was lower in fish fed the 9% L diets. Overall, liver and muscle fatty acid composition reflected that of diet FA composition, with increased n3/n6 ratio, high HUFA and low MUFA in fish fed FO compared with the VO diets. Higher liver glycogen content was observed in fish fed the 18% L than the 9% L diets, except for fish fed FO diet. Considering the experimental diets used, these results indicate that hybrid catfish can efficiently utilize VO supplementation as an energy source, without affecting growth performance and fillet composition.

Effect of slaughter weight on the quality of Nile tilapia fillets

The objective of this work was to evaluate the influence of slaughter weight on the expression of calpastatin, m-calpain and the RyR3 gene, and on the chemical composition, morphometric measurements, fillet yield and sensorial characteristics of Nile tilapia fillets. In the experiment, 90 Nile tilapia were divided into three experimental treatments regarding slaughter weight (n = 30): in treatment 1, tilapia aged 140 days were slaughtered with an average body weight of 665 ± 85 g; in treatment 2, the animals were slaughtered at 182 days and weighed 1000 ± 177 g; and in treatment 3, they were slaughtered at 238 days and weighed 1325 ± 167 g. There was no significant difference (P > .05) between the treatments for the chemical composition and fillet yield. Fillets of tilapia slaughtered with a weight of 665 g presented higher expression of m-calpain and lower expression of calpastatin gene, lower pH values of the thawed fillet, lower drip and thawing loss, and lower shear force than animals slaughtered with the highest evaluated weight. Tilapias slaughtered at 665 g also presented higher flavor and general acceptance. These results show that slaughter weight may influence important aspects of the quality of Nile tilapia fillets and that the slaughter of Nile tilapia with a body weight of 665 g allows fillets that serve the consumer market to be obtained.

Dietary Influence on Fillet Composition of Gilthead Sea Bream reared at High Water Temperature

Dietary Influence on Fillet Composition of Gilthead Sea Bream reared at High Water Temperature

Comparison of fat composition and chemical properties of fat extracts between fish fillets of selected warm-water and cold-water fish

The purpose of this study was to determine and compare fat composition and chemical properties of fish fillets of selected warm-water fish obtained from Straits of Malacca. A cold water fish, namely salmon was used for comparison. Moisture content, crude fat, fatty acids composition and chemical characteristics of fish fillets of Yellowstripe scad, Japanese threadfin bream and salmon were determined. Japanese threadfin bream fillet had highest moisture and crude fat contents, followed by fillets of Yellowstripe scad and salmon. A significantly strong and negative correlation was found between moisture and crude fat contents of these fish fillets. Fillets of Japanese threadfin bream and Yellowstripe scad also had higher total saturated fatty acids than total unsaturated fatty acids. Although salmon fillet had lowest percentage of saturated fatty acids, it had highest monounsaturated fatty acids and polyunsaturated fatty acids (PUFA) compared with the two warm-water fish. Palmitic acid and oleic acid were the major fatty acids in the fish fillets. Chemical properties of the oils extracted from the warm-water fish fillets were varied compared to salmon. The selected warm-water fish fillets offer favorable fatty acids composition and chemical properties, which can potentially be used as good sources of PUFA.

DIETS FOR GROW-OUT OF PIRARUCU IN NET CAGE: PERFORMANCE, PHYSIOLOGICAL PARAMETERS, FILLET COMPOSITION AND FEEDING COST

The present study evaluated practical diets with increasing levels of protein and energy on performance, fillet composition, feed cost, and physiological responses of pirarucu (Arapaima gigas) juveniles during the grow-out phase in a net cage system. In an on-farm trial for 90 days 225 pirarucu juveniles with initial weight ± standard deviation of 2025 ± 335 g were fed to apparent satiety with extruded diets containing 37.4 (T-37), 40.8 (T-40), 43.9 (T-43), 45.5 (T-46), and 47.1% (T-49) crude protein (CP), increasing lipid levels, and energy:protein ratio fixed in 10 kcal g-1. Protein and lipid concentrations in the diets influenced the cost, fillet composition, and important physiological aspects of the health maintenance and productive performance of the pirarucu juveniles. Fish fed the T-37 diet had lower concentrations of fat in body cavity, fillet and blood, and had a lower cost associated with feeding. The increase in protein and energy levels in the other diets tested reduced the economic return, did not improve the zootechnical performance and caused physiological changes in the fish.&#x0D;

Características morfométricas, rendimentos de cortes e composição centesimal do híbrido tambacu

Objetivou-se avaliar as características morfométricas, os rendimentos de cortes e a composição centesimal do híbrido tambacu. Utilizou-se 40 exemplares distribuídos em delineamento inteiramente casualizado, composto por quatro tratamentos referentes as classes de peso (T1= 800-1000g, T2= 1001- 1200g, T3= 1201-1400g e T4= 1401-1600g), e dez repetições. Foram avaliados os seguintes parâmetros morfométricos: comprimento da cabeça/comprimento padrão (CC/CP), comprimento da cabeça/altura da cabeça (CC/AC), comprimento padrão/comprimento total (CP/CT), largura do tronco/comprimento do tronco (LTR/CTR), largura do tronco/altura do tronco (LTR/ATR) e altura do troco/comprimento do tronco (ATR/CTR) e os seguintes rendimentos (%): carcaça (peixe eviscerado), tronco limpo, filé com pele, filé sem pele e da pele, sobras em “V”, índice de gordura visceral (IGV), espinhaço, cabeça e resíduos. Foram determinados, ainda, a composição centesimal utilizando-se cinco filés de cada classe de peso. Os parâmetros, CC/CP e LTR/ATR, apresentaram efeito da classe de peso (p&lt;0,05). Observou-se diferenças significativas entre os rendimentos de pele e índice de gordura visceral (IGV), com valores médios 8,55% e 3,05% respectivamente. Na avaliação da composição centesimal, apenas a umidade não apresentou diferença significativa entre os tratamentos. Os valores mais elevados de lipídios (LP) foram 10,54%, em T2 e proteína bruta (PB) 16,68%, em T4. Os exemplares com peso médio variando de 800 a 1600g, apresentam semelhanças tanto para as relações morfométricas quanto para rendimentos de cortes. Entretanto, os peixes da classe T4=1401-1600g, apresentam adequados níveis de lipídios e elevados valores de proteínas bruta nos filés de tambacu cultivado.