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991.
Juan Antonio De Anda-Montañez Ricardo Perez-Enriquez Susana Martínez-Aguilar Fidencio Hernández-Martínez Francisco Javier García-Rodríguez Alberto Amador-Buenrostro 《Fisheries Science》2013,79(1):21-32
This study reports the distribution, estimated abundance and biomass, and genetic population structure of the red crab Pleuroncodes planipes along the western coast of the Baja California Peninsula, Mexico. Using a hybrid conical net for fish and crustaceans, bottom trawls with stratified depth were performed at transect sites perpendicular to the coast. Red crab was observed to distribute widely in the study area, particularly in upwelling areas such as Bahia Magdalena and its surroundings, and the greatest catches were recorded at depths between 51 and 100 m, and between 201 and 300 m, with values of 2,297 and 3,223 kg/h of trawl, respectively. The population genetic analysis using mitochondrial DNA sequencing revealed no significant population differentiation. The total estimated biomass was 611,525 metric tons, supporting the proposal that the red crab is a viable exploitation resource in the study area. 相似文献
992.
993.
Ignacio Jauralde Silvia Martínez‐Llorens Ana Tomás Rodolfo Ballestrazzi Miguel Jover 《Aquaculture Research》2013,44(2):242-253
Modelling growth as a function of feeding rate (FR) could be one of the most important tools for fish farms, because this knowledge allows growth to be maximized, or the feed conversion ratio (FCR) to be minimized, thereby improving profits. All growth models should include the three principal variables involved in growth: initial body weight, temperature and feeding rate. The thermal‐unit growth coefficient (TGC) already includes water temperature variation and initial body weight. Studying variation in TGC for fish fed the same diet, but at several feeding rates provides interesting information for modelling. Six different trials were conducted where gilthead sea bream of several different initial weights (24, 38, 50, 110, 220 or 289 g) were fed increasing amounts, and growth and the conversion index response were measured. The TGC response was modelled as a function of FR, and both asymptotic and quadratic responses were examined. The asymptotic model, TGC × 1000 = 2.037*(1?e (?0.8*(FR?0.22)), had an adjusted R2 value of 96.18, whereas the quadratic model, TGC × 1000 = ?0.381 + 1,715 × FR?0,382 × FR2, had an adjusted R2 value of 96.42. Simulations of the FCR and the economical profitability index (EPI) were conducted to provide tools for maximizing efficiency and profitability, and the results suggest that these tools will be useful for future investigations. 相似文献
994.
da Silva Acosta D Kneip FC Alves de Almeida E Ventura-Lima J Monserrat JM Geracitano LA 《Fish physiology and biochemistry》2012,38(5):1477-1485
The carbon nanomaterial fullerene (C(60)) can act as anti or pro-oxidant. The aim of this study was to evaluate, in cell suspensions of carp brains (Cyprinus carpio, Cyprinidae), the effect of C(60) after a pre-treatment with polyunsaturated fatty acid (PUFAs) such as omega-3 (docosahexaenoic acid, DHA) and omega-6 (linoleic acid, LA). Assays consisted of a pre-treatment with PUFA (48?h) and then exposure to C(60) (2?h). Cell viability and total anti-oxidant capacity did not differ (p?>?0.05). A reduction (p?0.05) was observed in reactive oxygen species (ROS) and thiobarbituric acid reactive substances (TBARS) concentration in fish brain cells pre-exposed with PUFA groups and then exposed or not with C(60). An antioxidant effect of C(60) was evident since in control group (cells not pre-exposed to PUFA), a significant (p?0.05) reduction of intracellular ROS concentration was observed, although this reduction was not enough to reduce the TBARS levels. Cysteine levels presented a reduction (p?0.05) in all groups exposed to C(60). For glutathione (GSH), an increase (p?0.05) was registered in cells exposed to C(60) without PUFAs pre-treatment and in the C(60) group pre-treated with DHA. Overall C(60) appears to play an antioxidant role that is modulated by PUFA, taking into account its effects on intracellular ROS concentration and MDA levels. Results also suggest that C(60) influences GSH synthesis, as showed for the augmented levels of this antioxidant and also for the lowering of the intracellular cysteine concentration. 相似文献
995.
S. T. Tapia-Paniagua P. Díaz-Rosales J. M. León-Rubio I. García de La Banda C. Lobo F. J. Alarcón M. Chabrillón P. Rosas-Ledesma J. L. Varela I. Ruiz-Jarabo S. Arijo M. A. Esteban E. Martínez-Manzanares J. M. Mancera M. C. Balebona M. A. Mori?igo 《Aquaculture International》2012,20(6):1025-1039
The application of probiotics on aquatic animals is increasing for a better fish welfare status as well as an environment-friendly activity which are actual demands of modern aquaculture industry. A bacterium from skin mucus of healthy gilthead seabream (Sparus aurata L.) has been isolated and identified as Shewanella putrefaciens Pdp11. Different studies have been done to know its application as probiotic in the Senegalese sole and gilthead seabream farming. This article reviews the studies carried out with this probiotic microorganism focusing on the current knowledge of its in vitro and in vivo mechanisms of action. The results suggested that the probiotic S. putrefaciens Pdp11, due to its beneficial effects, could be used in the aquaculture activity of both species. 相似文献
996.
Ângela Angeloni RovarisCarolinne Odebrecht Dias Iria Pedroso da CunhaRejane Maria Cirra Scaff Alicia de FranciscoCarmen L.O. Petkowicz Edna Regina Amante 《Industrial Crops and Products》2012,36(1):405-414
The solid wastes were obtained from enzymatic extraction of soybean oil using four enzyme systems (Alcalase/Celluclast or Alcalase/Viscozyme L) each with two pH conditions: controlled or not controlled. This last option gave a better oil extraction, regardless of the enzymes used. The ash levels were higher for the enzyme systems subjected to controlled pH, depending on the buffer solutions used. The others constituents presented similar values between each other. The monosaccharides with highest concentrations were galactose, followed by glucose and arabinose. The physical analysis showed that the waste residues had good oil binding capacity. The SEM and epifluorescence microscopy revealed the microstructure of the beans and raw materials, as well as the changes caused by the extraction procedures. 相似文献
997.
S Prado J Dubert F da Costa D Martínez‐Patiño J L Barja 《Journal of fish diseases》2014,37(3):209-217
Hatchery culture of the razor clam, Solen marginatus (Pulteney), has recently been developed in Galicia (NW Spain). However, recurrent episodes of mortalities of larval and post‐larval cultures have been recorded during the course of various studies. The disease signs were similar to those described for other bivalve species in outbreaks caused by bacteria of the genus Vibrio. In this article, we present the results of microbiological monitoring of two batches of razor clams with different survival rates. All fermentative isolates were identified as members of the Splendidus clade within the genus Vibrio. Some of these isolates, identified as Vibrio splendidus‐like, were clearly associated with the batch suffering mortalities, indicating their possible role as pathogens. Similar strains were found in the broodstock, suggesting vertical transmission of these bacteria. This is the first study of the microbiota associated with hatchery culture of S. marginatus, and the results will provide useful information for the optimization of a protocol for hatchery culture of this bivalve species. 相似文献
998.
María Cristina Chávez-Sánchez Miguel Angel Olvera-Novoa Briseida Osuna-Durán Isabel Abdo de la Parra Selene María Abad-Rosales Irma Martínez-Rodríguez 《Aquaculture International》2014,22(6):1891-1909
A 13-week feeding trial was conducted to determine the optimal dietary ascorbic acid (AA) requirement of juvenile spotted rose snapper (Lutjanus guttatus). Six experimental diets containing 0, 7, 19, 29, 62 and 250 mg AA equivalent kg?1 diet, supplied as l-ascorbyl-2-polyphosphate designated as VC0, VC7, VC19, VC29, VC62 and VC250, were fed ad libitum to triplicate groups of 20 juveniles [initial weight (IW) of 8 ± 1.85 g]. Nutrient deficiency resulting in fin erosion, dark skin, desquamation and erratic swimming was observed after 8 weeks in fish fed diets from 0 to 29 mg AA kg?1. Fish that were fed all diets showed gill, kidney and brain alterations. The degree of tissue change values indicates that increasing vitamin C (VC) levels reduces these alterations. Fish fed diets VC29, VC62 and VC 250 showed a significantly higher growth rate in comparison with those fed the diets VC0, VC7 and VC17 (P > 0.05). The dietary requirement of VC in L. guttatus was estimated to be 29 mg kg?1 of AA based on weight gain and specific growth rate, but more than 250 mg kg?1 of AA is required to eliminate clinical signs and histopathological lesions. 相似文献
999.
Alicia Callejas-Chavero Gabriela Casta?o-Meneses María Razo-González Daniela Pérez-Velázquez José G. Palacios-Vargas Arturo Flores-Martínez 《Journal of insect science (Online)》2015,15(1)
Soil fauna is essential for ecosystem dynamics as it is involved in biogeochemical processes, promotes nutrient availability, and affects the animal communities associated with plants. In this study, we examine the possible relationship between the soil microarthropod community on foliage production and quality of the shrub Pittocaulon praecox. We also examine the arthropods associated to its foliage, particularly the size of the main herbivores and of their natural enemies, at two sites with contrasting vegetation cover and productivity. The diversity of soil microarthropods was assessed from soil samples collected monthly under P. praecox individuals over 13 mo. Specimens collected were identified to species or morphospecies. Shrub foliage productivity was evaluated through the amount of litter produced. Resource quality was assessed by the mean content (percentage by weight) of N, C, S, and P of 30 leaves from each shrub. The mean size of herbivores and their natural enemies were determined by measuring 20 adult specimens of each of the most abundant species. We found a higher species richness of soil microarthropods and foliar arthropods in the open site, although the diversity of foliage arthropods was lower in the closed site. Shrubs growing in the closed site tend to produce more, larger, and nutritionally poorer (lower nitrogen content) leaves than open site. Herbivores and their natural enemies were also larger in the closed site. We found a significant positive relationship between the diversity and species richness of foliar arthropods and the nitrogen content of leaves. In general, species richness and diversity of both the foliar and soil fauna, as well as the size of organisms belonging to higher trophic levels, were affected by vegetation cover and primary productivity at each site. These findings highlight the need to simultaneously consider at least four trophic levels (soil organisms, plants, herbivores, and natural enemies) to better understand the functioning of these systems and their responses to environmental changes. 相似文献
1000.
Selection of marine species and meals for cephalopod feeding based on their essential mineral composition 下载免费PDF全文
J. Cerezo Valverde A. Tomás Vidal S. Martínez‐Llorens M.C. Pascual J.I. Gairín J. Estefanell D. Garrido J.F. Carrasco F. Aguado‐Giménez B. García García 《Aquaculture Nutrition》2015,21(5):726-739
A quantitative analysis of the essential mineral content (mg kg?1 dry weight) was carried out in 31 samples, including molluscs, crustaceans, fish and meals in an attempt to identify those most suitable for formulating cephalopod diets. The mineral ratios (MR: content in the test sample/content in whole Octopus vulgaris) were used as index of nutritional quality. Both crustaceans and oysters presented an optimal profile that covered the macro‐ and microelements composition of O. vulgaris. These samples differed from the rest by their higher Ca, Mg, B, Cu and Zn contents based on a principal component analysis. Fish were deficient in macroelements, such as Na (MR: 70–420 g kg?1) and Mg (MR: 220–690 g kg?1), but would be good source of K, Ca and P. Most fish were also deficient in Fe, Zn and Cu, although the copper content would be the most affected (MR: 3–130 g kg?1). Fish and krill meals showed a high content of Ca and P, although both would be deficient in Na (MR: 440–470 g kg?1) and Cu (130–540 g kg?1), along with K, Fe and Zn in krill and Mg and B in fish. Among the plant meals, sunflower and soybean were the most appropriate, presenting higher total content of minerals and MRs above 1000 g kg?1 for all minerals, except Na, Cu and Zn. 相似文献