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81.
Scale matters: performance of European sea bass,Dicentrarchus labrax,L. (1758), reared in cages of different volumes 下载免费PDF全文
Athanasios Samaras Michael Pavlidis Konstadia Lika Antonia Theodoridi Nikos Papandroulakis 《Aquaculture Research》2017,48(3):990-1005
The effects of rearing volume on on‐growing European sea bass performance and stress parameters were investigated for the first time in a pilot aquaculture farm. Fish were held under the same initial stocking densities in triplicate net‐pen cages of different sizes (1.4, 45 and 252 m3) for a period of 8 months. Results showed significant differences among the experimental groups in most parameters tested, with better performance in the two larger rearing volumes. In particular, growth rate showed a linear association with rearing volume, being 0.68 g day?1 for the large cage group, 0.56 g day?1 and 0.32 g day?1 for the medium and the small groups respectively. The feed conversion ratio and per cent survival (%) were also better in the large cage group. Fish reared in the small and medium‐sized cages showed higher plasma cortisol concentrations than those reared in large cages, which showed low basal cortisol concentrations. Additionally, after an acute chasing stress challenge, fish in the large and small groups, but not the medium group, showed increased cortisol concentrations. Differences also occurred in the ratio of the expression of cortisol receptors, namely the mineralocorticoid (mr) and glucocorticoid receptors (gr). In specific, the ratio of mr to grmRNA expression in the liver was higher in fish reared in the small cages. These findings verify that experimental scale significantly affects experimental results and is a critical factor for the interpretation of results. 相似文献
82.
Hilary J. Burgess Betty P. Lockerbie Lisanework E. Ayalew Antonia Dibernardo Kristýna Hrazdilov David Modry Trent K. Bollinger 《Journal of veterinary diagnostic investigation》2021,33(6):1188
We developed a PCR assay for the detection of Babesia odocoilei based on the 18S rRNA gene. Multiple specimens of B. odocoilei were examined, and the assay consistently produced a small specific PCR product of 306 bp. The PCR assay was also challenged with DNA from 13 other Babesia species and 2 Theileria species, originating from 10 different host species; however, nonspecific DNA amplification and multiple banding patterns were observed, and the amplicon banding patterns varied between different isolates of the same species. Sensitivity was determined to be 6.4 pg of DNA, and an estimated 0.0001% parasitism. This assay can be utilized for species-specific differential detection of B. odocoilei. 相似文献
83.
Application of gas chromatography coupled to triple quadrupole mass spectrometry for the multiresidue analysis of pesticides in olive oil 总被引:1,自引:0,他引:1
Garrido Frenich A Fernández Moreno JL Martínez Vidal JL Arrebola Liébanas FJ 《Journal of agricultural and food chemistry》2007,55(21):8346-8352
A new multiresidue method has been developed and validated for the simultaneous determination of 100 pesticide residues in olive oil. The determination of pesticide residues was carried out in only 19 min by gas chromatography coupled to tandem mass spectrometry using a triple quadrupole mass analyzer. The mass spectrometer was operated in electron ionization and the selection reaction monitoring mode was used, acquiring two or three fragmentation reactions per compound. Two extraction processes were studied, and an evaluation of the stability and sensitivity of the chromatographic system has been performed for the tested extraction procedures. The final proposed methodology was based on a liquid-liquid partition with an n-hexane/acetonitrile mixture followed by a gel permeation chromatography cleanup step. An adequate lineal relation was obtained in the studied concentration range (10-200 microg kg (-1)); the recovery values were in the range 70-110% for the two levels of concentration studied: 12 and 50 microg kg (-1). Precision values, expressed as relative standard deviation, were lower than 18% at the aforementioned spiking levels; detection limits, confirmation limits, and quantitation limits were below or equal to 1.9, 2.6, and 3.6 microg kg (-1), respectively. The developed methodology was applied to the analysis of pesticide residues in real samples of olive oil from the south of Spain. 相似文献
84.
Severino Segato Daniela Bertotto Luca Fasolato Antonia Francescon Alvise Barbaro & Adolfo Corato 《Aquaculture Research》2006,37(1):71-77
Productive performances of triploid (3n) and diploid (2n) shi drum (Umbrina cirrosa L.) were evaluated over an experimental period of 76 days. Fish, selected according to body weight (196 specimens from each ploidy), were reared in tanks (two for each thesis) under the same environmental and dietary conditions. A practical extruded diet (crude protein: 43.4%; ether extract: 19.3%) was offered to fish according to a feeding rate that varied from 1% to 1.5% of live weight. Both at the beginning and at the end of the trials, samples of fish were submitted to morphometrics and chemical analysis. The final body weight and the specific growth rate of triploid fish were significantly lower than those of fish diploid. The feed efficiency of triploids showed a reduction in crude protein retention. Juvenile triploids evidenced a larger amount of coelomatic fat, and their gonads were atrophic. The whole‐body proximate composition of 3n fish was characterized by a higher ether extract and a lower crude protein content than 2n fish. Triploids had higher liver lipid content; there were no significant differences in viscera proximate composition. Sum, the results showed that chromosome set manipulation in this species can reduce productive performances at a juvenile stage, influencing some morphometric traits. 相似文献
85.
Montilla A Olano A Martínez-Villaluenga C Corzo N 《Journal of agricultural and food chemistry》2011,59(19):10705-10711
The influence of reaction conditions for oligosaccharide synthesis from stachyose using a commercial enzymatic preparation from Aspergillus aculeatus (Pectinex Ultra SP-L) was studied. Oligosaccharides were analyzed by gas chromatography with flame ionization detection (GC-FID) and matrix-assisted laser desorption/ionization-time-of-flight-mass spectrometry (MALDI-TOF-MS). Galactosyl-melibiose (DP(3)) was synthesized as a result of fructosidase activity, whereas fructosyl-stachyose (DP(5)) and difructosyl-stachyose (DP(6)) were formed as a consequence of the fructosyltransferase activity of Pectinex Ultra SP-L. The optimal reaction conditions for the synthesis of penta- and hexasaccharides were 60 °C, pH 5.5, 600 mg/mL stachyose, and 34 U/mL enzyme. Reaction time played an important role in oligosaccharide mixture composition constituted by 20% DP(5), 0.7% DP(6), 55% stachyose, 21% galactosyl-melibiose, and 1% monosaccharides after 1 h and 16% DP(5), 4% DP(6), 27% stachyose, 44% galactosyl-melibiose, and 2% monosaccharides after 3 h. In conclusion, stachyose could be used as a substrate for the enzymatic synthesis of new oligosaccharides that may open new opportunities in the development of future prebiotics. 相似文献
86.
Rosalía Lpez-Ruiz Jesús Marín-Sez Antonia Garrido Frenich Roberto Romero-Gonzlez 《Pest management science》2022,78(1):19-29
In the last few years, the cultivation of cannabis has been increasing due to greater use in foods, recreational use, creams, oils, and other applications. Thus, analysis of contaminants (e.g. pesticides and mycotoxins) in cannabis products is necessary to ensure consumer safety. This review is focused on the analytical procedures, based on chromatographic techniques, used for the determination of contaminants in cannabis and related products, developed from 2015 to 2020. QuEChERS (acronym of quick, easy, cheap, effective, rugged and safe) was mainly used for the extraction of pesticides and other contaminants from cannabis because its versatility and capacity to extract a wide range of substances, and therefore, increasing the scope of the analysis. The most employed technique to determine pesticides and mycotoxins in cannabis products was liquid chromatography (LC) coupled to mass spectrometry (MS), although gas chromatography (GC) coupled to MS was also employed for the analysis of non-polar compounds, using triple quadrupole (QqQ) as mass analyzer. Nevertheless, new advances in cannabis analysis are also discussed, introducing techniques such as high-resolution mass spectrometry (HRMS), which allows for performing both targeted and untargeted (unknown and suspect) analyses. © 2021 Society of Chemical Industry. 相似文献
87.
Antonia L. Moreira Arnaud A. Alves Daniel L. C. Araújo Miguel A. Moreira Filho Jandson V. Costa Danielle M. M. R. Azevêdo Henrique N. Parente Fabiana C. Alves 《Animal Science Journal》2021,92(1):e13508
The present study was conducted to evaluate the intake, digestibility and nitrogen balance of diets for finishing sheep, containing leucaena hay as a source of effective fibre and forage palm. Twenty-one male sheep were used in a randomized block design with three treatments, represented by total diets, where the forage was leucaena hay and forage palm in natura in proportions 350:650, 450:550 and 550:450 g/kg respectively. For the pH and NH3-N in the ruminal fluid, and urea in the blood serum, plots split in time were adopted. Dry matter and nutrient digestibility, and the nitrogen balance were not influenced (p > .05) by the diets. The neutral detergent fibre digestibility decreased (p < .05) as the proportions of leucaena hay in the diets increased. The pH and NH3-N were suitable for ruminal fermentation, and blood urea was maintained under normal physiological conditions for sheep. Combining 350 to 550 g/kg of leucaena hay with 450 to 650 g/kg of forage palm in total diets with a forage:concentrate ratio of 60:40 in late-maturing sheep meets the nutritional requirements for daily gain 200 g, characterizing leucaena hay as important source of effective fibre and nutrients in diets. 相似文献
88.
Ang CY Hu L Heinze TM Cui Y Freeman JP Kozak K Luo W Liu FF Mattia A DiNovi M 《Journal of agricultural and food chemistry》2004,52(20):6156-6164
Several bioactive botanicals including St. John's wort (SJW; Hypericum perforatum L.) have been used to formulate functional foods and beverages. This study aimed to investigate the stability of SJW components in aqueous solutions and fruit-flavored drinks. Changes of active marker components (hypericin, pseudohypericin, hyperforin, and adhyperforin) as affected by pH and light exposure were determined by HPLC, and the degradation of hyperforin was analyzed by LC-MS/MS and NMR. SJW components were found to be unstable in acidic aqueous solutions. More changes occurred under light exposure, with hyperforin and adhyperforin decreasing the most. Less severe changes were observed in the drink sample as compared to the pH 2.65 solution. Major degradation products of hyperforin in acidic aqueous solutions were identified as furohyperforin, furohyperforin hydroperoxide, and furohyperforin isomer a. The latter was also found in the drink product containing SJW as an ingredient. Biological activities and potential quality and safety implications of these chemical changes are yet to be evaluated. 相似文献
89.
Fernández-Bolaños J Rodríguez G Gómez E Guillén R Jiménez A Heredia A Rodríguez R 《Journal of agricultural and food chemistry》2004,52(19):5849-5855
A process for the value addition of solid waste from two-phase olive oil extraction or "alperujo" that includes a hydrothermal treatment has been suggested. In this treatment an autohydrolysis process occurs and the solid olive byproduct is partially solubilized. From this water-soluble fraction can be obtained besides the antioxidant hydroxytyrosol several other compounds of high added value. In this paper three different samples of alperujo were characterized and subjected to a hydrothermal treatment with and without acid catalyst. The main soluble compounds after the hydrolysis were represented by monosaccharides xylose, arabinose, and glucose; oligosaccharides, mannitol and products of sugar destruction. Oligosaccharides were separated by size exclusion chromatography. It was possible to get highly purified mannitol by applying a simple purification method. 相似文献
90.