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This study evaluated the ambient noise effect of onshore and offshore aquaculture systems on oxidative status and on some immune parameters in gilthead sea bream (Sparus aurata) juveniles. The experiment was performed for 40 days, projecting two different playlists of acoustic stimuli: offshore aquaculture noise condition that created the typical acoustic field in proximity of an offshore sea cage for fish farming, using a random sequence of quite sea background and boat noises; and onshore aquaculture noise condition that represented the acoustic field inside an open concrete tank for fish farming. A third group without any acoustic projection was used as a control. After 40 days from the beginning of acoustic noise, fish exposed to the offshore aquaculture condition showed significantly higher levels of total oxidant status, lysozyme activity, antiprotease activity and white blood cells together with a lower albumin/globulin ratio in comparison to fish from the control group; whereas fish exposed to the onshore condition showed analytical data placed between the other groups, though never significantly different. These results demonstrate that the offshore aquaculture noise, and in particular the sea soundscape, adversely influences the oxidative status and the immune function of gilthead sea bream determining a mild stress condition that could affect the sea bream welfare.  相似文献   
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This study shows a pilot scale protocol aimed to obtain an omega 3-enriched oil after the processing of farmed gilthead sea bream viscera (SBV); this was oil was tested in vitro for bioactivity, attesting to the possibility to turn waste into profit The quality of the oil, in terms of requirements for animal and human consumption, was assessed by determining some chemical parameters, such as peroxide value (PV), thiobarbituric acid reactive substances (TBARS), ρ-anisidine (ρ-AV) content, total oxidation value (TOTOX), and phospholipids and free fatty acid (%), both in crude viscera oil (CVO) and refined viscera oil (RVO). Among the extraction conditions, the higher CVO yields were obtained at 60 °C for 10 min (57.89%) and at 80 °C for 10 min (67.5%), and the resulting oxidation levels were low when utilizing both extraction conditions. RVO, obtained from CVO extracted at 60 °C, showed the highest quality on the basis of the assessed parameters. The ethyl esters of the total fatty acid (TFA) contents extracted from RVO were enriched in the ω-3 polyunsaturated fatty acid fraction (PUFAE) up to almost 56% via short path distillation (SPD). Antioxidant activities and adipogenic properties were tested in vitro. PUFAE protected 3T3 L1 cells from oxidative stress and exerted an anti-adipogenic effect in Dicentrarchus labrax pre-adipocytes, attesting to the beneficial properties for both farmed fish and human health. These results could stimulate the adoption of solutions aimed to recover and utilize aquaculture by-products at a higher scale, turning “waste into profit” and indicating a strategy to reach more sustainable business models in aquaculture resource utilization according to the principles of the circular economy.  相似文献   
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Water-, salt-, alcohol- and alkali-soluble seed storage proteins, extracted from 21 cipolla bianca di Pompei landraces (Allium cepa L.), were analyzed by anionic exchange-high performance liquid chromatography (AE-HPLC). Chromatographic elution profiles (time range 0–40 min) at 280 nm of water-soluble seed proteins evidenced the presence of 21 peaks, which allowed all the landraces studied to be distinguished from each other. The differences detected were both qualitative (presence/absence of one or more peaks) and quantitative; the water-soluble proteins were useful in differentiating landraces and cultivars while the other seed protein fractions only showed a weak polymorphism. The cluster analysis, based on HPLC data, showed that the landraces clustered with a genetic similarity degree ranging between 69% and 94%. The possibility of discriminating among closely related onion landraces during the course of breeding programmes could allow the identification of biochemical markers linked to useful agronomical traits. As observed by chromatographic analysis, the globulin composition of onion water-soluble seed protein appears to be independent of environmental growth conditions. The biochemical characterization of the available typical onion germplasm may contribute to obtain a community recognition and denomination, such as Denomination of Protected Origin (D.O.P.), Indication of Protected Origin (I.G.P.) or Specificity Attestation (A.S.). The biochemical method here developed resulted of high resolution, cost-effective and time-saving for characterization and genetic purity assessment of the landraces studied.  相似文献   
155.
To determine milk yield and composition, total microbic count (TMC) and somatic cell count (SCC) of browsing goats throughout the first lactation, 100 goats of Sarda breed, equally distributed in four flocks (F1, F2, F3 and F4), were selected. They were exclusively fed pasture and hand‐milked once daily. Individual milk samples and daily milk yield were taken from each goat at monthly intervals, from March to July. Milk samples were analyzed for: total protein, fat, lactose, urea, freezing point (FP), pH, TMC and SCC. The data was subjected to analysis of variance and to correlation matrix. On the whole, in all the flocks, milk yield showed the highest production in April and May. Fat content increased (P < 0.01) throughout the lactation. Protein content showed the lowest value (P < 0.01) in June (4.15%). Urea and pH values were fluctuating. FP was lower (P < 0.01) at the start of lactation (?0.562 Hortvet degrees). TMC log10 values were low, considering the hand milking and inadequacy of facilities on the farms. SCC increased (P < 0.01) throughout the lactation and, on the whole, SCC and TMC were not correlated.  相似文献   
156.
In the last two decades, the emergence and spread of antimicrobial-resistant pathogens, among them Salmonella, has become a serious health hazard worldwide, and specifically the high incidence of multidrug resistance has been encountered widely in many European countries. This study examines the antimicrobial supsceptibility of Salmonella enterica strains Typhimurium and Enteritidis isolated in Campania and Calabria region (Southern Italy) from animal and food of animal origin. The relationship of antibiotic resistance phenotype and the presence of some resistance genes has been also investigated. As espected, our results showes that resistance to ampicillin, chloramphenicol, streptomycin, sulphonamides and tetracycline is common, although resistance to other antibiotics (i.e.:nalidixic acid) and other resistance patterns occur. The genetic resistant patterns have been partially described for this food-borne pathogen but efforts are needed to realize the complete characterization of antimicrobial resistance genes.  相似文献   
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