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The aim of this study was to assess the PCB pollutionof the South-Western branch of Lake Como by using thezebra mussel (Dreissena polymorpha) as abioindicator since its recent reintroduction. Someenvironmental and physiological variables influencingaccumulation processes of organochlorine compounds inDreissena were investigated because climaticfactors may affect life cycle, reproductive stage andage. PCB levels were highest in the soft tissues ofDreissena close to the industrialized area ofComo (2298 ng g-1 of lipids) and slowly decrease goingnorth, reaching approximately half this value at theclosing section of the lake branch. Nonetheless, thePCB concentrations are well below the dangerous levelsfor the aquatic environment. 相似文献
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A large scale study on the western basin of Lake Como (N. Italy) was started in 1995 to examine the effects of the zebra mussel colonization which began in early '90. Our results have been related to '91–92 data (pre-Dreissena period), before the maximum colonization of zebra mussel. In spring and summer of the post-Dreissena period total phosphorus, P-PO4, nitrate and chlorophyll values decreased, while ammonium and tranparency increased at every sampling station. Zebra mussel does not modify the trophic state of this sub-basin but it plays an important role in nutrient cycling. The entire population can filter epilimnetic craters 2.1 times per year and can produce 2.9 × 104 t y of pseudofaeces which are transferred to sediments. 相似文献
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Roberta Bettinetti Silvana Galassi Silvia Quadroni Pietro Volta Fabrizio Capoccioni Eleonora Ciccotti Giulio A. De Leo 《Water, air, and soil pollution》2011,217(1-4):321-331
One of the aims of the Water Framework Directive 2000/60/CE is to assess the ecological status of water bodies in Europe in relation to priority contaminants, including some persistent organic pollutants (POPs). Recognizing the benefits of measuring hydrophobic compounds in biota tissues rather than in water, we used the European eel Anguilla anguilla in the present study as a bioindicator species for monitoring POPs in freshwater/brackish environments. We present the results of a contamination analysis of eels carried out in three Italian sites representative of different pollution levels: the last part of Tevere River, which flows through a very urbanized and industrialized area, Caprolace Lake and Lesina Lagoon, inside two different protected national parks. A very high pollution variability was recorded within each group of eels, in particular for those caught at Caprolace Lake. Due to this high variability, inter-population comparisons were carried out only between eels collected in Tevere River and Lesina Lagoon. PCBs values in Lesina Lagoon were two orders of magnitude lower than those measured in Tevere River, while no significant differences were found for levels of DDT compounds. Our results confirm the suitability of the eel as an indicator of persistent bioaccumulative pollutants in brackish environments and rivers where it can be easily caught, but we are sceptical of its use in deep lakes where its capture might be problematic considering standard operation procedures for fish sampling. 相似文献
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Tiziano Cembali Raymond J. Folwell Philip Wandschneider Kenneth C. Eastwell William E. Howell 《Crop Protection》2003,22(10):1149-1156
Viral diseases in fruit trees present a potential danger that could injure the fruit industry, the planting stock industry (nurseries), and consumers in the United States and abroad. Currently, the US has a virus protection program (VPP) that serves to minimize the spread of viral diseases. This paper reports research estimating the economic consequences of the loss of the program on nurseries, growers and consumers. The potential economic losses are a measure of the value of the existing program. The paper focuses on apples, sweet cherries, and Clingstone peaches.
The effects of a loss of a VPP on nurseries would include direct and indirect losses from viral diseases in the form of lower quantity and quality of planting stocks. Fruit growers would be affected by reduced plant growth and fruit yield. Consumers would be affected by higher prices and reduced quantity of fruit.
We measured benefits of the virus prevention program as changes in consumer and producer surpluses. Empirical estimates were made using the method of avoided losses. Benefit estimates to three economic sectors—nurseries (avoided change in producer surplus), producers (avoided change in consumer and producer surpluses), and consumers (avoided change in consumer surplus)—were calculated. Total benefits for all three sectors were approximately $227.4 million a year, or more than 420 times the cost of the program. Our analysis utilizes a method that might be used to evaluate other programs that prevent the introduction of plant diseases. 相似文献
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Ellingsen Ståle Narawane Shailesh Fjose Anders Verri Tiziano Rønnestad Ivar 《Fish physiology and biochemistry》2021,47(5):1507-1525
Fish Physiology and Biochemistry - System b0,+ absorbs lysine, arginine, ornithine, and cystine, as well as some (large) neutral amino acids in the mammalian kidney and intestine. It is a... 相似文献
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D Galassi P Galassi A Pelliccioni P Semprini 《Comparative immunology, microbiology and infectious diseases》1986,9(2-3):285-295
The conditioned infections due to opportunistic organisms, can be controlled by biological immunostimulators. The POLI-IF (Newcastle virus plus endotoxin of E. coli and Freund's incomplete adjuvant) rapidly induces the aspecific immunity. Given twice with 7-10 days interval in between, on occasion of a programmed stress (weaning, transport, crowding) it proved its efficacy in artificially suckled calves and in weaning piglets. The field trials, carried out on 2,782 treated calves in comparison with 2,909 untreated controls and on 4,387 piglets in comparison with 4,461 untreated controls, revealed statistically significant differences for P less than 0.005 among the groups of treated and control animals. The immunostimulator reduced the incidence of the disease, dead and discarded animals, as well as it shortened the mean duration of the disease in single heads. Though the way the POLI-IF acts is not perfectly known so far, yet it increases the serum bactericidal activity and the circulating leukocytes, while it induces high levels of IFN. In our opinion the activity of the POLI-IF is bound to 3 factors at least: activation of the complementary fractions, mobilization of the immunocompetent cells, induction of IFN. 相似文献
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Marta Mari Tiziano Cembali Lucia Casalini Gian Carlo Pratella 《European journal of plant pathology / European Foundation for Plant Pathology》2000,106(5):449-454
Strains of Mucor piriformis were isolated from orchard soils and from packinghouse dump-tank waters. Pathogen propagules were not found in fruit sample washings. M. piriformis was the most prevalent of the Mucor isolates, only one of 67 isolates was a different Mucor sp., possibly M. racemosus. The population of the pathogen propagules fluctuated in an annual cyclic pattern, declining in warm months and increasing after harvest. The viability of sporangiospores was markedly affected by rain. There was a good correlation (r=0.88) between the number of recovered propagules in the soil and the amount of rainfall. M. piriformis isolates caused decay on pear at 0°C after 14 days. 相似文献
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Removal of ochratoxin A in red wines by means of adsorption treatments with commercial fining agents
Castellari M Versari A Fabiani A Parpinello GP Galassi S 《Journal of agricultural and food chemistry》2001,49(8):3917-3921
The presence in wine of the fungal metabolite, ochratoxin A (OTA), represents a serious risk for consumer health. A variety of fining agents, including activated carbon, silica gel, potassium caseinate, egg albumin, and gelatin, was evaluated in relation to their abilities to remove OTA in fortified wines. Freundlich adsorption isotherms were used to model the adsorption behavior between ochratoxin A and the fining agent. Potassium caseinate and activated carbon were found to be the best fining agents that could be used to remove OTA in wine. Potassium caseinate removed up to 82% of OTA when used at 150 g/hL, whereas activated carbon showed the highest specific adsorption capacity due to a high surface area per mass and low adsorption of total polyphenols. 相似文献
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Effects of a selection of additives on in vitro ruminal methanogenesis and in situ and in vivo NDF digestibility 
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下载免费PDF全文 Mario Pirondini Stefania Colombini Luca Malagutti Luca Rapetti Gianluca Galassi Raffaella Zanchi Gianni Matteo Crovetto 《Animal Science Journal》2015,86(1):59-68
The effects of 18 essential oils, yeast, Quebracho tannin and Quillaja saponin on ruminal methane and gas production (GP) were studied in vitro. A lactating cow diet was incubated with rumen inoculum. Doses of the additives (mg/L) were: essential oils = 500; tannin = 67; yeast = 8.35 and 16.7; and saponin = 300. Lemongrass, estragole, eugenol, geraniol, limonen, thyme oil and thymol produced less gas (overall mean 33.8 mL/200 mg dry matter (DM)) than control (43.6 mL/200 mg DM; P < 0.001). Methane produced (mL/200 mg DM) by guaiacol (10.7), lemongrass (9.6), limonene (11.4), thyme oil (10.9) and thymol (2.1) was lower than control (12.5) (P < 0.001). Methane percentage on total GP was lower (P < 0.001) for cinnamic alcohol (25.4), guaiacol (24.5), thymol (19.7) and vanillin (26.3) than control (28.8). In a second experiment, thymol, guaiacol and yeast were added to the diet of dry fistulated cows to determine in situ neutral detergent fiber digestibility (NDFD) of six forages and in vivo dietary NDFD. Thymol and yeast decreased in situ NDFD after 24 h (33.9% and 33.5% vs. 38.1%; P = 0.008). Thymol decreased in vivo total tract NDFD (40.8% vs. 51.4%; P = 0.02). Differences in GP and methane levels were registered within classes of additives. A careful selection of additives may allow for the manipulation of ruminal fermentation. 相似文献