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251.
Carlos Navarro-Barranco Juan Moreira Free Espinosa Macarena Ros Ioannis Rallis Juan Sempere-Valverde Enrique Ostalé-Valriberas María Altamirano J. Carlos García-Gómez José M. Guerra-García 《水产资源保护:海洋与淡水生态系统》2021,31(9):2305-2319
- This work constitutes the first comprehensive study of the epifaunal response to biological invasions in coralligenous habitats, which are one of the main hotspots of biodiversity in the Mediterranean.
- The epifaunal community inhabiting the invasive macroalga Rugulopteryx okamurae and other dominant sessile hosts on coralligenous habitats (i.e. the sponge Spongia lamella, the gorgonian Paramuricea clavata, and the macroalga Sphaerococcus coronopifolius) was characterized. A total of 137 taxa were found.
- There was a lack of functional equivalence between macroalgal species (both native and invasive) and sessile invertebrates. Despite the absence of significant differences in mean density values and number of species per replicate among host species, epifaunal composition on gorgonians and sponges differed significantly from that on both macroalgae.
- Epifaunal assemblages, especially those inhabiting macroalgal species, were dominated by generalist detritivorous species that can inhabit different hosts, while specialized interactions between mobile epifauna and sessile hosts were observed almost exclusively on sessile invertebrates. Moreover, epifaunal community associated with invertebrate hosts showed higher spatial heterogeneity in comparison with native and invasive macroalgae.
- A competitive displacement of native hosts by the spreading of R. okamurae on coralligenous habitats would likely result in a biotic impoverishment in terms of overall number of species and a taxonomical and functional homogenization of the epifaunal community. Specialist species with a heterogeneous distribution could be gradually replaced by a spatially homogeneous assemblage dominated by generalist species.
252.
Evagelos Dimitriou George Katselis Dimitrios K Moutopoulos Constantin Akovitiotis & Constantin Koutsikopoulos 《Aquaculture Research》2007,38(4):398-408
More than 25% of Greek fish farms and 20% of Greek hatcheries of gilthead sea bream (Sparus aurata) and sea bass (Dicentrarchus labrax) are located along the Western Hellenic coast. The part of sea bream production is about 60% of the total production of these species. During the last decade, a spectacular increase in both the number of farms and their production, accompanied by a substantial price decrease and modification of their structure and functioning, has been recorded. These changes resulted in the maintenance in cages of large individuals (more than 500 g) of gilthead sea bream which are potential spawners. The study, based on both the maturity stage and the decrease in individual mean weights during the reproductive period of the species, confirmed reproduction in cages. In parallel, during the last 5 years a remarkable increase (about 80%) in sea bream landings from the fish trap fisheries of the Messolonghi‐Etoliko lagoon, which is a typical nursery for the species, was recorded. The increase was accompanied by a decrease both in price and mean size of the 0‐group individuals. The possible influence of the rearing activities in the area, the density‐dependent mechanisms and the negative impacts of this unintentional enhancement of the traditional lagoon fisheries of the area are discussed. 相似文献
253.
Stijn Schauvliege Johannes Peter Schramel Kiriaki Pavlidou Ioannis Savvas Luc Duchateau Frank Gasthuys Yves Moens 《Veterinary anaesthesia and analgesia》2014,41(6):592-601
ObjectiveTo compare breathing patterns and transdiaphragmatic pressure during total intravenous (TIVA) and isoflurane anaesthesia in ponies.Study designExperimental, cross–over study.AnimalsSix healthy ponies weighing 286 (233–388) ± 61 kg, age 13 (9–16) ± 3 years.MethodsFollowing premedication with romifidine [80 μg kg?1 intravenously (IV)], general anaesthesia was induced with midazolam (0.06 mg kg?1 IV) and ketamine (2.5 mg kg?1 IV) and maintained with either isoflurane (Fe’Iso = 1.1%) (T-ISO) or an IV combination of romifidine (120 μg kg?1 per hour), midazolam (0.09 mg kg?1 hour?1) and ketamine (3.3 mg kg?1 hour?1) (T-TIVA), while breathing 60% oxygen (FIO2). The circumference changes of the rib cage (RC) and abdominal compartment (ABD) were recorded using respiratory ultrasonic plethysmography (RUP). Balloon tipped catheters were placed in the distal oesophagus and the stomach and maximal transdiaphragmatic pressure (Pdi max) was calculated during Mueller's manoeuvre.ResultsThe breathing pattern T-ISO was more regular and respiratory rate significantly lower compared with T-TIVA. Ponies in T-TIVA showed regularly appearing sighs, which were never observed in T-ISO. Different contribution of the RC and ABD compartments to the breathing pattern was observed with a smaller participation of the RC to the total volume change during T-ISO. Transdiaphragmatic pressures (mean 13.7 ± SD 8.61 versus 23.4 ± 7.27 cmH2O, p < 0.0001) were higher in T-TIVA compared to T-ISO. The sum of the RC and ABD circumferential changes was lower during T-TIVA compared to T-ISO (6.32 ± 4.42 versus 11.72 ± 4.38 units, p < 0.0001).Conclusion and clinical relevanceMarked differences in breathing pattern and transdiaphragmatic pressure exist during inhalation- and TIVA and these should be taken into account for clinical estimation of anaesthetic depth. 相似文献
254.
Ioannis A. Papaioannou Eleftherios K. Ligoxigakis Demetrios J. Vakalounakis Emmanouil A. Markakis Milton A. Typas 《European journal of plant pathology / European Foundation for Plant Pathology》2013,136(3):577-596
A population of 84?V. dahliae isolates mainly originating from Crete, Greece, was characterized in terms of pathogenicity and virulence on different hosts, in parallel with morphological/physiological characterization, vegetative compatibility grouping and mating type determination. Tomato race 2 was found to have supplanted race 1 and was more virulent on a tomato-susceptible cultivar than race 1. Using a differential host classification system which tests pathogenicity to tomato, eggplant, sweet pepper and turnip, 59 isolates were assigned to tomato, 19 to eggplant, one to sweet pepper and five to tomato-sweet pepper pathogenicity groups. All isolates from Crete fell into VCG subgroups 2A, 2B and 4B, while a remarkably high incidence of bridging isolates (compatible with two or more VCGs) was recorded. The tomato-sweet pepper pathogenicity group was morphologically quite distinct from the others, while conidial length and pigment intensity were discriminatory parameters among VCGs 2A, 2B and 4B. PCR-based molecular marker Tr1/Tr2 was reliable in race prediction among tomato-pathogenic isolates, except for members of VCG 4B, while the application of markers Tm5/Tm7 and 35-1/35-2 was highly successful for tomato-pathogenic isolates. E10 marker was related to VCG 2B, rather than to pathogenicity groups. A single nucleotide polymorphism in the ITS2 region, and two novel molecular markers, M1 and M2, proved useful for the fast and accurate determination of major VCGs 2A, 2B and 4B, and can be used for high-throughput population analyses in future studies. The mating type was unrelated to VCG classification and probably does not control heterokaryon incompatibility in V. dahliae. 相似文献
255.
Vassilios Triantafyllidis Dimitra Hela Maria Papadaki Dimitrios Bilalis Ioannis Konstantinou 《Water, air, and soil pollution》2012,223(4):1625-1637
The soil mobility and dissipation of two pesticides with different physicochemical properties, namely mefenoxam, a systemic
fungicide, and pendimethalin a selective herbicide, were determined in bare and tobacco tilled soil columns, which were installed
in field conditions for over 125 days. Soil samples were collected at specific time intervals for a 125-day period and the
rate of pesticide dissipation and leaching through the soil column was studied. The dissipation half-lives of mefenoxam from
the top soil layer in tilled and bare soil columns were estimated at 10.3 and 13.1 days, respectively, while the corresponding
half-lives for pendimethalin were 26.7 and 27.5 days, respectively. The dissipation of mefenoxam and pendimethalin from the
top soil in tobacco cultivation was faster in comparison with bare soil; however, 120 days after their application, both pesticide
residues were detected in the soil. Maximum concentrations of mefenoxam and pendimethalin were observed on the 15th and 33rd day, respectively, in the soil layer of 5–10 cm depth and on the 30th day and 63rd day, respectively, in the soil layer of 10–15 cm depth. Higher concentrations were observed in bare soil columns. The leaching
of both pesticides was simulated with the continuous stirred tank reactor (CSTR) in series model. The simulated peak concentration
and peak time for both pesticides fitted reasonably well to the experimental values. 相似文献
256.
Irakli MN Samanidou VF Papadoyannis IN 《Journal of agricultural and food chemistry》2012,60(9):2076-2082
The separation and determination of tocopherols (Ts) and tocotrienols (T3s) by reversed-phase high-performance liquid chromatography with fluorescence detection has been developed and validated after optimization of various chromatographic conditions and other experimental parameters. Analytes were separated on a PerfectSil Target ODS-3 (250 × 4.6 mm, 3 μm) column filled with a novel sorbent material of ultrapure silica gel. The separation of Ts and T3s was optimized in terms of mobile-phase composition and column temperature on the basis of the best compromise among efficiency, resolution, and analysis time. Using a gradient elution of mobile phase composed of isopropanol/water and 7 °C column temperature, a satisfactory resolution was achieved within 62 min. For the quantitative determination, α-T acetate (50 μg/mL) was used as the internal standard. Detection limits ranged from 0.27 μg/mL (γ-T) to 0.76 μg/mL (γ-T3). The validation of the method was examined performing intraday (n = 5) and interday (n = 3) assays and was found to be satisfactory, with high accuracy and precision results. Solid-phase extraction provided high relative extraction recoveries from cereal samples: 87.0% for γ-T3 and 115.5% for δ-T. The method was successfully applied to cereals, such as durum wheat, bread wheat, rice, barley, oat, rye, and corn. 相似文献
257.
258.
Ioannis E. Papadakis Stavros Chatzifotis Pascal Divanach Maroudio Kentouri 《Aquaculture International》2008,16(1):13-25
The weaning of greater amberjack (Seriola dumerilii Risso 1810) to a dry diet was studied in two consecutive experiments. The experimental fish were hatchery-produced and grown
to their initial size on a soft pellet containing 50% trash fish and 50% commercial dry pellet. In the first experiment, three
homogenous groups of greater amberjacks (n = 153, mean weight: 374 ± 43 g), initially adapted for a period of 30 days to a diet with a 40% moisture content, were fed
on commercial pellets containing three different levels of dietary moisture (7, 20 and 40%, respectively) for 126 days. We
found that fish needed a month to adapt to the 7%- and 20%-moisture diets and that moisture content of the diet had a significant
effect on fish growth in terms of increasing feed consumption and lowering feed conversion ratio. The group fed on the 20%-moisture
diet not only compensated for the initial adaptation period but presented the higher growth rate and best feed conversion
ratio. In the second experiment, all groups of experiment 1 were fed the same commercial diet with a 7% moisture content for
72 days. The group that had been previously fed on the 20%-moisture diet showed the best growth performance. The implication
of the above results for the weaning of greater amberjack to dry diets is discussed in terms of the digestion process and
physiology. 相似文献
259.
Morphological and free amino acid profile variability,as a tool for stock identification among farmed rainbow trout Oncorhynchus mykiss of different origin 下载免费PDF全文
Petros V Martsikalis Menelaos Kavouras Georgios A Gkafas Apostolos P Apostolidis Ioannis S Boziaris Athanasios Exadactylos 《Aquaculture Research》2018,49(2):621-630
As a tool for stock identification the body morphology and the free amino acid (FAA) profile variability were determined among farmed rainbow trout Oncorhynchus mykiss (Walbaum 1792) from different geographical areas throughout Greece, using geometric morphometrics and Reversed Phase‐High‐Performance Liquid Chromatography. Significant intraspecific body shape variation was detected among the fish stocks of different origin. Canonical Variate Analysis distinguished populations into two groups being consistent to a great extent with a previous population genetics study. General linear models did not support an association of haplotypes and diet with shape. However, shape was significantly correlated with origin, water temperature, geological‐chemical‐climatic zones, histidine and arginine. Therefore, morphological variation was primarily driven by environmentally induced differences among these zones being the result of phenotypic plasticity. Environmental cues and rearing conditions played the pivotal role in comparison to broodstock origin. Specimens presented different FAA profiles depending on their geographical origin. Principal Component Analysis showed a division between eastern and western Greece which might be owed to the existence of climatic fluctuations affecting the abiotic factors. This combined approach offers an important tool for stock identification thus assisting environmental risk assessments in evaluation of potential ecological effects and fostering research excellence in sustainable aquaculture management. 相似文献
260.
Alexios Glaropoulos Vassilis M. Papadakis Ioannis E. Papadakis Antonia Georgara Maroudio Kentouri 《Aquaculture International》2014,22(3):1203-1214
The technology of floating sea cages that is largely used in the Mediterranean aquaculture provides optimal conditions for the development of marine fouling. The present study investigates the influence of micro-fouling developed on a net, on sea bream behavior. Negative effects of biofouling were not tested since the study was performed under laboratory conditions and for short experimental period. The net condition (micro-fouling filaments) is further examined in comparison with a similar green–brown colored and a white net pen. From the results obtained, it can be concluded that micro-fouling filaments highly induce net biting. In contrast, the colored net tested in this study negatively affected sea bream interactions on the net. Results lead to the conclusion that the fouling filaments are more important to sea bream attraction than the net color, while both variables affect species behavior. 相似文献