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Aline F. S. Carvalho Monica R. Ferreira Machado Estefnia S. Andrade Luis D. S. Murgas Mrcio G. Zangeronimo Thiago C. Barros Fernanda G. Paula 《Journal of the World Aquaculture Society》2014,45(1):75-81
The aim was to evaluate the effect of different concentrations of caffeine added in activating solution over sperm motility in fresh and thawed semen of pacu, Piaractus mesopotamicus, and curimba, Prochilodus lineatus. The activating solutions were prepared with sodium bicarbonate solution of 0.76% (NaHCO3) and caffeine was added at concentrations of 2.5, 5.0, 10.0, and 20.0 mM. As control, a solution of NaHCO3 0.76 without caffeine was used. Eight males of pacu and 20 males of curimba were used. Aliquots of 200 μL of semen were diluted in 800 μL extender solution (DMSO 10% and BTS 5%), placed in 0.5 mL straws and cryopreserved for 7 d in a liquid nitrogen tank. There was a linear increase in sperm motility for fresh semen of pacu, and for curimba fresh and thawed semen (P < 0.05), due to the increase in the concentration of caffeine. There was a quadratic response for duration of motility for thawed semen of pacu and for fresh semen of curimba (P < 0.05), respectively. These results indicate that addition of caffeine in the activator solution can improve sperm motility parameters, however, is dependent on the species and concentration used. 相似文献
3.
Marco Grella Fabrizio Gioelli Paolo Marucco Ingrid Zwertvaegher Eric Mozzanini Marco Pittarello Paolo Balsari Spyros Fountas David Nuyttens Monica Mezzalama Massimo Pugliese 《Pest management science》2023,79(11):4423-4438
Background
In order to improve the biological control agent (BCA) efficacy, stress factors threatening the viability of microorganisms during spray application need to be determined. The effect of spray mixture temperature and exposure time on Trichoderma harzianum T 22 and Bacillus amyloliquefaciens QST713 viability were tested. Concurrently the combined effect of mechanical and thermal stress effect on BCA viability were tested at two initial spray mixture temperatures (14 and 25 °C) by simulating a spray application using airblast sprayers featured by different tank capacity and a spray liquid circuit (without and with hydraulic agitation system). To assess the BCA microorganism viability, spray mixture samples were collected at time intervals along trials and plated to count the colony forming units (CFU).Results
The critical temperature threshold that inhibited BCA viability was 35 °C with 30 min of exposure. The sprayer type, the initial temperature of the spray mixture and the temperature increment during the trials significantly decreased the number of CFU recovered. When simulating a spray application, the spray mixture temperature increase rate was determined mainly by the residual amount of spray mixture in the tank. Even if the tank capacity does not substantially affect the final temperature reached by the spray mixture, the higher residual spray mixture in bigger tanks can expose the BCAs for a longer time to critical temperatures.Conclusions
Experimental trials allowed us to identify the effect of factors affecting the viability of tested BCAs, providing information about the actual chance to guarantee the biological efficacy of BCA treatments. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献4.
Christopher Marlowe A Caipang Monica F Brinchmann Ingvild Berg Martin Iversen Robert Eliassen Viswanath Kiron 《Aquaculture Research》2008,39(14):1533-1540
Using Atlantic cod, Gadus morhua, as a model for the stress response in gadoid fish, the changes in the expression of some stress and immune genes as well as the profiles of plasma cortisol were examined. Adult fish were kept at a density of ca. 100 kg m?3 by lowering the water level in the rearing tank for 1 h and this short‐term crowding stress was repeated thrice over a 12‐h interval period. Blood samples were collected before exposure and at 2, 24 and 72 h post crowding. Plasma cortisol level significantly increased at 2 h post crowding but returned to pre‐crowding levels 24 h after exposure. The relative expression of the stress response genes, glucose transporter‐3 and a putative heat shock protein 70 significantly increased at 2 and 24 h post crowding respectively. Significant up‐regulation of the pro‐inflammatory cytokines, interleukin (IL)‐1β and IL‐8, as well as anti‐bacterial genes, g‐type lysozyme and bactericidal permeability‐increasing protein/lipopolysaccharide‐binding protein (BPI/LBP) was also observed at 2 h and the levels were maintained until 72 h post exposure, except for BPI/LBP which had maximum up‐regulation at 24 h. The present observations have implications with respect to fish welfare and assessment of the health status of the farmed fish. 相似文献
5.
Soy isoflavones have been correlated with beneficial health effects. The predominant chemical forms of isoflavones present may affect their biological activities. Choosing the solvent system that can accurately quantify the amounts of individual isoflavones present in these products is paramount. Our objectives were to compare frequently used solvent systems and to evaluate the effects of polarity and acidity on the recovery of isoflavones from soybeans. Isoflavones were extracted from pulverized Manokin soybeans using six solvent systems, which are the combinations of three polarity levels (83% acetonitrile, 80% methanol, and 58% acetonitrile) and two acidity levels (nonacidified and acidified). The pulverized soybean was stirred for 2 h in each solvent system before filtration and concentration using rotary evaporation. The extract was resuspended in 16% acetonitrile and analyzed by high-performance liquid chromatography. Recoveries of pure standards were evaluated with all solvent systems. Solvents with a higher polarity extracted a significantly higher amount of total isoflavones. For individual isoflavones, 58% acetonitrile (highest polarity) extracted either the highest amounts or no less than other solvents, while 83% acetonitrile (lowest polarity) extracted either the lowest amounts or no more than other solvents except for the aglycone form. Acidification significantly reduced the recovery of the malonylglucoside form and the total isoflavones. The recovery study revealed that acidification favored the chemical transformations of isoflavones during the extraction. Among the six solvent systems examined, 58% acetonitrile aqueous solution without acid was the best for extraction of isoflavones from soybeans. 相似文献
6.
Sabine Augustin Jan Evers Hans-Peter Dietrich Johannes Eichhorn Thomas Haussmann Regina Icke Ansgar Isenberg Wolfgang Lux Monica Musio Hans Pretzsch Winfried Riek Thomas Rötzer Bernd Schultze Andreas Schulze Jörg Schröder Walter Seidling Nicole Wellbrock Klaus von Wilpert Barbara Wolff 《European Journal of Forest Research》2005,124(4):251-260
In the 1970s unexpected forest damages, called “new type of forest damage” or “forest decline”, were observed in Germany and
other European countries. The Federal Republic of Germany and the German Federal States implemented a forest monitoring system
in the early 1980s, in order to monitor and assess the forest condition. Due to the growing public awareness of possible adverse
effects of air pollution on forests, in 1985 the ICP Forests was launched under the convention on long-range transboundary
air pollution (CLRTAP) of the United Nations Economic Commission for Europe (UN-ECE). The German experience in forest monitoring
was a base for the implementation of the European monitoring system. In 2001 the interdisciplinary case study “concept and
feasibility study for the integrated evaluation of environmental monitoring data in forests”, funded by the German Federal
Ministry of Education and Research, concentrated on in-depths evaluations of the German data of forest monitoring. The objectives
of the study were: (a) a reliable assessment of the vitality and functioning of forest ecosystems, (b) the identification
and quantification of factors influencing forest vitality, and (c) the clarification of cause-effect-relationships leading
to leaf/needle loss. For these purposes additional data from external sources were acquired: climate and deposition, for selected
level I plots tree growth data, as well as data on groundwater quality. The results show that in particular time series analysis
(crown condition, tree growth, and tree ring analysis), in combination with climate and deposition are valuable and informative,
as well as integrated evaluation of soil, tree nutrition and crown condition data. Methods to combine information from the
extensive and the intensive monitoring, and to transfer process information to the large scale should be elaborated in future.
相似文献
Sabine AugustinEmail: |
7.
Context
Cultural ecosystem services, many of which depend on biodiversity, are recognized as important but seldom quantified biophysically across landscapes. Furthermore, many ecosystem service models are static, and the supply of cultural ecosystem services may be misrepresented if seasonal shifts in biotic communities are ignored.Objectives
We modeled landscape dynamics of wildflower blooms in a temperate montane landscape to determine (1) how floral resources (wildflower species richness, abundance, timing, and presence of charismatic species) changed over the growing season, (2) how projected wildflower viewing hotspots varied over space and time, and (3) how spatial shifts in floral resources affected potential public access to wildflower viewing.Methods
Data were collected at 63 sites across a rural-to-urban gradient in the Southern Appalachian Mountains (USA). Generalized linear models were used to identify factors affecting floral resources at two temporal scales. Floral resources were projected across the landscape and hotspots of wildflower viewing were quantified using overlay analysis.Results
Floral resources were affected by topoedaphic conditions, climate, and surrounding building density and changed seasonally. Seasonal models revealed locational shifts in ecosystem service hotspots, which changed the proportion of hotspots accessible to the public and identified wildflower-viewing opportunities unnoticed by static models.Conclusion
Relationships between landscape gradients, biodiversity, and ecosystem service supply varied seasonally, and our models identified cultural ecosystem service hotspots otherwise obscured by simple proxies. Landscape models of biodiversity-based cultural ecosystem services should include seasonal dynamics of biotic communities to avoid under- or over-emphasizing the importance of particular locations in ecosystem service assessments.8.
Iñiguez AM Carvalho VL Motta MR Pinheiro DC Vicente AC 《Veterinary parasitology》2011,175(3-4):293-299
Prevalence and seasonal variations of helminth infections and their association with morbidity parameters were studied in traditionally reared Cambodian cattle. Four villages in two provinces of West Cambodia were visited on monthly intervals over a period of 11 months, during which 2391 animals were faecal and blood sampled for parasitological and haematological examinations. The body condition score (BCS), faecal consistency (diarrhoea score, DS), colour of the ocular conjunctivae (FAMACHA(?)) and packed cell volume were determined for each individual animal. The overall proportion of samples that was positive for gastrointestinal nematodes was 52%, 44% and 37% in calves (from 1 to 6 months), young animals (6 to 24 months) and adults (over 24 months), respectively, while geometric mean faecal egg counts (FECs) for each of these age categories were 125, 66 and 15 eggs per gram, respectively. Six genera of strongyles were found in the faecal cultures, i.e. in descending order of occurrence, Cooperia, Oesophagostomum, Haemonchus, Trichostrongylus, Mecistocirrus and Bunostomum. The prevalences of Fasciola and Paramphistomum, estimated by coprological examination, varied between 5-20% and 45-95%, respectively. Logistic mixed models were used to investigate associations of morbidity markers with the presence of parasite infection. A low BCS was associated with gastrointestinal nematode and liver fluke infections, and soft faecal consistency with Paramphistomum infections. However, other factors such as nutritional deficiencies and intercurrent diseases are likely to enhance the effects of parasites and should therefore be considered when using these morbidity parameters as indicators of parasitism. 相似文献
9.
10.
Venner M Markus RG Strutzberg-Minder K Nogai K Beyerbach M Klug E 《Berliner und Münchener tier?rztliche Wochenschrift》2008,121(1-2):66-72
In 360 samples of colostrum and 36 samples of blood of warmblood mares, the concentration of immunoglobulin G (IgG) was evaluated in the post partal period with an ELISA and the results were compared to values obtained with 2 field methods--refractometry and colostrometry. A significant correlation (p < 0.0001) was determined between ELISA and colostrometry (r = +0.88) and between ELISA and refractometry (r = +0.93). So both field-methods seem suitable for evaluation of the colostral IgG-concentration in mares. Further the kinetic of the IgG concentration in colostrum, the volume of colostrum and the total amount of IgG was measured in the 12 hours post partum (p.p.) in each half udder of 36 mares of different parity. Immediately p.p. primiparous mares have a greater mean concentration of IgG (68 mg/ml) than multiparous mares (51 mg/ml). However, multiparous mares have a mean colostral volume of 1020 ml whereas, in primiparous mares, a mean volume of 527 ml was determined within the first three hours p.p. As a result of this the total amount of IgG was lower in primiparous (31.5 g) than in multiparous mares (48.5 g). A significant decrease of IgG concentration was measured in multiparous mares in the 1.5 hours following partum versus 3 hours in primiparous mares. The mean IgG concentration in the blood serum of the 36 mares immediately p.p. was 13.4 +/- 3.6 mg/ml. No significant correlation was observed between values of IgG concentration in the blood and in the colostrum of the mares. 相似文献