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131.
Rubn Alonso Contreras‐Tapia María Elena Castellanos‐Pez S. Nandini Marcela Ivonne Benítez‐Díaz‐Mirn Gabriela Garza‐Mourio 《Aquaculture Research》2020,51(5):2102-2111
The effect of a commercial probiotic (NanoCrusta, Altacrusta, Mexico City, Mexico) on the growth performance of Brachionus calyciflorus Pallas, 1766, was evaluated. In a first approach, probiotics were supplied in four densities (2.0 × 103, 1.1 × 105, 2.1 × 105 and 2.1 × 106 cells/ml), alone and in combination with Chlorella vulgaris (1 × 106 cells/ml). The test rotifer did not grow on the probiotic alone. However, when probiotics + C. vulgaris were added, the maximum densities (Dmax; ind/ml) and population growth rates (r) observed were higher. In the second experiment, probiotics were supplied at five higher densities (2.1 × 106, 4.2 × 106, 8.5 × 106, 1.7 × 107 and 3.4 × 107 cells/ml) with C. vulgaris and a control treatment with only C. vulgaris (probiotic‐free). Treatments supplied with probiotics between 2.1 × 106 and 1.7 × 107 cells/ml showed significantly higher Dmax and r than the control treatment. The results showed a positive effect of probiotic bacteria when supplied with C. vulgaris. The best outcome showed a Dmax 2.16 times and an r 1.63 times higher than the density of the control treatment. Growth rates were higher in the treatments with probiotics compared to the control. We conclude that application of NanoCrusta is feasible to improve B. calyciflorus production, but the effects need to be tested in larger scales. 相似文献
132.
Luis Daniel Jimnez‐Martínez Dariel Tovar‐Ramírez Carlos Alfonso lvarez‐Gonzlez Emyr Pea‐Marín Susana Camarillo‐Coop Rafael Martínez‐García Elena Palacios‐Mechetnov Rosario Martínez‐Yaez Bartolo Concha‐Frías 《Aquaculture Research》2020,51(7):2629-2640
Five experimental diets containing different lipid sources, fish oil (D1), soybean lecithin (D2), corn oil (D3), canola oil (D4) and olive oil (D5), were evaluated in Atractosteus tropicus larvae for the relative gene expression of the enzymes fatty acid synthase (fas), acetyl‐CoA carboxylase 1 (acc1) and carnitine palmitoyltransferase 1C (cpt1c), in addition to their effects on larval growth, survival and cannibalism during a 30‐day feeding trial. Higher growth and survival were obtained in treatments D1 and D2, and lower performance in diets D3, D4 and D5. The highest levels of expression of fas and acc1 occurred in larvae fed with D1, which contained high amounts of n‐3 long‐chain polyunsaturated fatty acids (LC‐PUFA), mainly DHA and EPA FA are regulators of lipogenesis. The higher cpt1c expression in plant‐based diets is attributed to the fact that these diets are rich in α‐linolenic acid (ALA) and low DHA, EPA and ARA levels that favour ß‐oxidation. In conclusion, the diets with fish oil (D1) and soybean lecithin (D2) were the best treatments for larval growth, survival and cannibalism and thus appear to meet both lipid and energy requirements of A. tropicus larvae, meanwhile the use of vegetable oils influences the expression of intermediary lipogenic genes. 相似文献
133.
Ioannis T. Karapanagiotidis Pier Psofakis Elena Mente Emmanouil Malandrakis Eleni Golomazou 《Aquaculture Nutrition》2019,25(1):3-14
Two feeding trials examined the replacement of fishmeal (FM) with poultry by‐product meal (PBM) in the diet of juvenile Sparus aurata. In Feeding trial I (100 days), three diets were formulated, where FM protein was replaced by 50% (PBM50) and 100% (PBM100) PBM, while in Feeding trial II (110 days), four diets were formulated using the same FM control diet, but FM was replaced at lower levels: 25% (PBM25), and 25% (PBM25 + ) and 50% (PBM50 + ) with the supplementation of lysine and methionine amino acids. PBM protein can successfully replace 50% of FM protein in the diet of S. aurata without adverse effects on survival, feed intake, growth performance and feed utilization, given that the diet is balanced with lysine and methionine. The proximate composition of body and muscle was unaffected by the diet, but the total FM replacement resulted in reduced lipid and energy contents in fish. A fifty per cent FM replacement by PBM did not affect haematological parameters indicating a good fish health. Similarities in trypsin and chymotrypsin activities with FM‐fed fish suggest a high digestibility of PBM. High dietary levels of PBM reduced the liver gene expression of GH/IGF axis and of cathepsin D suppressing fish growth and modulating the protein turnover. 相似文献
134.
Houguo Xu Bo Sun Zhangbin Liao Elena Pribytkova Qinggong Zhang Yuliang Wei Mengqing Liang 《Aquaculture Research》2019,50(12):3528-3538
Our previous studies have indicated that dietary arachidonic acid (ARA) significantly affects the gonadal steroidogenesis in the marine teleost tongue sole Cynoglossus semilaevis, and this effect was more positive in male fish than in female fish (Aquaculture, 468, 378–385). As a following up study, the present study was further aimed at investigating the possible mechanisms in the brain mediating the effects of dietary ARA on gonadal steroidogenesis. A 70‐day feed trial was repeated with two‐year‐old tongue sole, using three experimental diets with graded levels of ARA, 0.34%, 2.53%, and 9.63% of total fatty acids. Each diet was fed to triplicate groups of 23 fish (15 males and 8 females). The results confirmed the positive effect of dietary ARA on testosterone production in male fish. The concentration of gonadotrophin‐releasing hormone (GnRH) in serum responded to dietary ARA in a similar pattern with the testosterone concentration, but the concentration of gonadotrophin in serum was not affected by dietary ARA. The response of gene expression of PKCβ, ARRB1, ARRB2, ERK2 and ATF3 in the brain to dietary ARA was in good agreement with those of GnRH and testosterone, indicating the possible involvement of PKC‐ARRB‐ERK‐ATF3 pathway in signalling transduction of GnRH. However, the PI3K/Akt and TLR/NF‐κB pathways may not be directly involved in the regulation of GnRH metabolism by ARA. This is the first study reporting the possible involvement of PKC/MAPK pathways in regulation of reproductive endocrine processes by long‐chain polyunsaturated fatty acid in brain of marine fish. 相似文献
135.
Sushkova Svetlana Minkina Tatiana Deryabkina Irina Mandzhieva Saglara Zamulina Inna Bauer Tatiana Vasilyeva Galina Antonenko Elena Rajput Vishnu K?z?lkaya R?dvan 《Journal of Soils and Sediments》2018,18(6):2361-2367
Journal of Soils and Sediments - The investigation of accumulation, migration, and transformation features of benzo[a]pyrene (BaP) in a soil-plant system by using new ecologically friendly... 相似文献
136.
137.
Wei Xiao Liu Yuqiao Zhan Qiang Zhang Pengbo Zhao Dandan Xu Bo Bocharnikova Elena Matichenkov Vladimir 《Paddy and Water Environment》2018,16(1):173-181
Paddy and Water Environment - Numerous greenhouse and laboratory experiments have shown that the application of Si-rich materials may affect the mobility and transport of hazardous elements in the... 相似文献
138.
Carlos Sanz-Lazaro Victoria Fernandez-Gonzalez Pablo Arechavala-Lopez David Izquierdo-Gomez Elena Martinez-Garcia Pablo Sanchez-Jerez 《Aquaculture International》2018,26(5):1161-1170
Bivalve cultivation, in single cultivation or in polyculture (including integrated multitrophic aquaculture; IMTA), is generally limited to eutrophic waters. We carried out a modeling study to test if, under meso- and oligotrophic conditions, depth could be a key factor for bivalve productivity associated to IMTA and other polyculture strategies. We applied the model Farm Aquaculture Resource Management (FARM) at three strata of the water column in two coastal fish farm areas in the Mediterranean Sea, using water column variables sampled seasonally to estimate the potential mussel production. According to FARM, mussel production was high in both areas and, in some cases, almost doubled when mussels were cultured below 25-m depth compared to shallower levels. Phytoplankton abundance is expected to notably influence mussel production compared to particulate organic matter. Thus, in meso- and oligotrophic stratified waters, where chlorophyll maximum is relatively deep, depth can be a key factor for the productivity of mussel cultivation. The obtained results could help to maximize the production of suspension-feeding bivalve cultivation and, therefore, the expansion and development of sustainable aquaculture in non-eutrophic marine waters. 相似文献
139.
Vladimir A. Basiuk Marco Salerno Alejandro Heredia Elena V. Basiuk 《Fibers and Polymers》2018,19(8):1632-1639
Bolas spiders of the genus Mastophora are very uncommon orb-weaver spiders, famous for their unusual predatory behavior. Being strictly nocturnal and very cryptic, they are extremely difficult to reveal, which explains their rarity in world arachnological collections. After a recent finding of an adult female of Mastophora corpulenta Banks (one of especially rare representatives of the genus), a few egg cases of this species became available, which seem to be very different from those of more common spiders due to their unusual hardness and coloration. We characterized some spectral, structural, and mechanical properties of this unusual silk material, by using Fourier-transform infrared spectroscopy, scanning electron microscopy (SEM), 3D profilometer imaging, and atomic force microscopy (AFM). For comparison, similar studies were performed for egg cases of the Southern black widow Latrodectus mactans Fabricius, since spiders of the genus Latrodectus are known to produce silk fibers of comparable toughness. Some similarities were observed between the silks produced by Mastophora corpulenta and Latrodectus mactans in terms of the size and chemical composition of egg cases. At the same time, SEM imaging and AFM force characterization revealed striking differences between them, due to the fact that Mastophora egg cases, unlike those produced by more common Araneae species, includes a solid (fused) wall, lacking evident porous structure, which results in their outstanding stiffness and strength. 相似文献