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991.
992.
Renan Rosa Paulino Rodrigo Fortes‐Silva Martha Janeth Prieto‐Guevara Edgar Junio Damasceno Rodrigues Leandro Santos Costa Anglica Priscila do Carmo Alves Aires Oliva Teles Priscila Vieira Rosa 《Aquaculture Research》2020,51(4):1567-1583
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. 相似文献
993.
Matheus D. Baldissera Carine F. Souza Keiti O. Alessio Katiane W. Krawczak Lorenzo B. Abbad Aleksandro S. da Silva Csar Bizzi Aline F. Ourique Carla C. Zeppenfeld Bernardo Baldisserotto Mauro A. Cunha 《Aquaculture Research》2020,51(10):4196-4205
The aim of this study was to determine whether feed supplementation with nanoencapsulated Ph2Se2 would improve the growth performance of silver catfish and would maintain or improve the muscle antioxidant system. Final mean weight (p = .031), weight gain (p = .014) and specific growth rates (p = .045) were significantly higher in supplemented fish than in the control group. Muscle reactive oxygen species (p = .0001) levels were significantly lower in supplemented fish than in the control group. Also, muscle hydrogen peroxide (p = .0001) and lipid peroxidation (p = .0001) levels were significantly lower in supplemented fish than in the control group. Muscle antioxidant capacity against peroxyl radical (p = .00001) levels were significantly higher in fish supplemented with both Ph2Se2 forms (free or nanocapsules) than in the control group, while muscle superoxide dismutase (p = .001) and catalase (p = .0001) activities were significantly higher in supplemented fish than in the control group. Finally, selenium (Se) deposition (p = .00001) was significantly higher in the muscle of fish supplemented with free and nanoencapsulated forms compared with the control; and deposition levels were significantly higher in fish supplemented with Ph2Se2‐loaded in nanocapsules compared with the free form. Based on this evidence, Ph2Se2‐loaded in nanocapsules improves silver catfish performance and antioxidant/oxidant status. The greater content of Se (1.22 µg/g muscle) in the muscle of fish fed with dietary Ph2Se2‐loaded nanocapsules indicates that it may be considered a nutraceutical for fish. 相似文献
994.
Rayette Souza da Silva Juliana Ralica Tavares Lopes Roberto Vilhena do Espírito Santo Marcos Antnio Souza dos Santos Carlos Alberto Martins Cordeiro Eliane Tie Oba Yoshioka Roselany Corrêa Heitor Martins Júnior Jos Brito de Loureno Júnior 《Aquaculture Research》2020,51(8):3358-3366
Two experiments were carried out to evaluate the effects of palm kernel meal (Elaeis guineensis) as corn (Zea mays) substitutes in tambaqui (Colossoma macropomum) diets based on zootechnical performance, health, characteristics of the muscle, yield and economic efficiency. The first one was carried out in a recirculation aquaculture system for 75 days wherein tambaquis received diets with 0% (T0), 25% (T25), 50% (T50), 75% (T75) and 100% (T100) of corn replacement by palm kernel meal. The second experiment, conducted in ponds for 184 days, tambaquis were fed T0 and T25 diets (selected because showed greater weight gain without health damage). Final weight and weight gain of tambaquis were impaired by the increasing levels of this ingredient on diets, and the feed conversion ratio was worse. The protein efficiency ratio and specific growth rate gradually reduced, while the total number of leucocytes and neutrophils gradually increased. Cholesterol and triglycerides decreased in T75 and T100. Variables analysed in experiment 2 were not affected by treatment, except muscle lipids. Palm kernel meal can replace up to 25% of corn in tambaqui diets since it maintains a balance in economic and zootechnical performance of production. 相似文献
995.
996.
Kifayat Ullah Khan Robert Mervyn Gous Cleber Fernando M. Mansano Thiago Matias T. Nascimento Rafael de S. Romaneli Andressa Tellechea Rodrigues Nilva Kazue Sakomura Joo Batista K. Fernandes 《Aquaculture Research》2020,51(9):3729-3740
This 45‐day work aimed to determine the response of juvenile pacu (Piaractus mesopotamicus) to balanced digestible protein (BDP) and to use these responses to determine whether the optimum economic levels of BDP would differ depending on the form in which the fish is sold. Six isoenergetic diets containing 163, 201, 238, 272, 315 and 348 g/kg BDP (dry‐matter basis) were prepared through the serial dilutions of a high‐protein diet with the low‐protein diet. Fish (initial average body weight, 10.82 ± 0.14 g) were fed with respective experimental diets three times a day until apparent satiation. The optimum biological level of BDP was calculated as 326 g/kg (dry‐matter basis) by the quadratic regression model for maximum body weight gain of juvenile pacu. To maximize economic returns (US$/kg) for different end products, the optimum economic levels of BDP were calculated as 311, 317 and 319 g/kg (dry‐matter basis) by an economic model for whole‐body, eviscerated and sliced juvenile pacu respectively. This finding revealed that obtaining maximum biological performance of fish in the case of high feed costs or low prices of the end product in consumer market would substantially reduce the economic returns. 相似文献
997.
998.
999.
Bruno dos Santos Sosa Evandro Bilha Moro Riccio Luan Marques Gomes Matheus dos Santos Cardoso Leonardo Machado Cardoso Wilson Rogrio Boscolo Jos Dilson Silva de Oliveira Altevir Signor Fbio Bittencourt 《Aquaculture Research》2020,51(7):2758-2765
The objective of this study was to evaluate the inclusion of increasing levels of a commercial mix of essential oils (EOs) from cashew (Anacardium occidentale) and castor bean (Ricinus communis) as an additive in diets for Nile tilapia. Thus, 240 juveniles with an initial weight of 35.06 ± 1.02 g were distributed in a completely randomized design (four treatments and six replicates) in 24 cylindrical‐tapered tanks; the fish were fed for 60 days, four times a day, diets containing increasing levels of EO (0.10, 0.15 and 0.20%) and a control diet (without the additive). After the experimental period, the animals were desensitized, and an aliquot of blood was collected for the biochemical analysis; they were subsequently euthanized for the evaluation of productive performance and fillet chemical composition. No significant differences (p > .05) were observed in the analyses of productive performance, fillet chemical composition, and triglycerides, VLDL, total proteins, urea and glucose. However, significant differences (p < .05) were observed in the analyses of total cholesterol, HDL and LDL. Inclusion above 0.15 of the additive showed an improvement in the levels of lipoprotein carriers, increasing HDL levels and decreasing LDL values, without interfering with the fish productive performance. 相似文献
1000.
Welliene M. Santos Leandro S. Costa Jose F. Lpez‐Olmeda Natlia Cristina S. Costa Fabio A. C. Santos Pedro G. Gamarano Walisson S. Silva Priscila V. Rosa Ronald K. Luz Paula A. P. Ribeiro 《Aquaculture Research》2020,51(7):2973-2984
While some studies have investigated the effects of dietary protein on the activities of protease in Nile tilapia, little information exists about these enzymes and hormones regulating appetite at the molecular level. Therefore, we investigated the performance, protease activities and expression of genes related to protein intake and digestion in juvenile tilapia fed with diets containing different levels of crude protein (CP): 25.14, 31.12, 36.60 and 42.05%. The fish were fed to apparent satiation three times a day for 65 days. The animal performance and the retention rates of protein and energy linearly decreased with an increase in dietary CP content. A positive quadratic effect of CP on pepsinogen was observed, although the acid protease activity was not affected. Trypsinogen and trypsin activity in the intestine presented similar patterns, showing a positive quadratic response to dietary protein levels. A linear increase in intestinal chymotrypsinogen expression was observed, but the activity of chymotrypsin showed a positive quadratic response. In addition, the expression of cholecystokinin (cck) and peptide yy (pyy) increased linearly with increasing CP. Dietary protein modulates the activity of alkaline proteases as well as the expression of these protease genes and hormones involved in appetite regulation. These changes can help expand our understanding of feed intake and digestion control, thereby improving feed formulations for this species. 相似文献