High yield and rapid growth of Neoparamoeba pemaquidensis in co-culture with a rainbow trout gill-derived cell line RTgill-W1     

Lee LE  Van Es SJ  Walsh SK  Rainnie DJ  Donay N  Summerfield R  Cawthorn RJ 《Journal of fish diseases》2006,29(8):467-480

Neoparamoeba pemaquidensis is an ubiquitous amphizoic marine protozoan and has been implicated as the causative agent for several diseases in marine organisms, most notably amoebic gill disease (AGD) in Atlantic salmon. Despite several reports on the pathology of AGD, relatively little is known about the protozoan and its relationship to host cells. In this study, an in vitro approach using monolayers of a rainbow trout gill cell line (RTgill-W1, ATCC CRL-2523) was used to rapidly grow large numbers of N. pemaquidensis (ATCC 50172) and investigate cell-pathogen interactions. Established cell lines derived from other tissues of rainbow trout and other fish species were also evaluated for amoeba growth support. The amoebae showed preference and highest yield when grown with RTgill-W1 over nine other tested fish cell lines. Amoeba yields could reach as high as 5 x 10(5) cells mL(-1) within 3 days of growth on the gill cell monolayers. The amoebae caused visible focal lesions in RTgill-W1 monolayers within 24 h of exposure and rapidly proliferated and spread with cytopathic effects destroying the neighbouring pavement-like cells within 48-72 h after initial exposure in media above 700 mOsm kg(-1). Disruption of the integrity of the gill cell monolayers could be noted within 30 min of exposure to the amoeba suspensions by changes in transepithelial resistance (TER) compared with control cell monolayers maintained in the exposure media. This was significantly different by 2 h (P < 0.05) compared with control cells and remained significantly different (P < 0.01) for the remaining 72 h that the TER was monitored. The RTgill-W1 cell line is thus a convenient model for growing N. pemaquidensis and for studying host-pathogen interactions in AGD.  相似文献   

Effect of Oyster Mushroom,Pleurotus ostreatus,Extract on Hemato‐Immunological Parameters of Rainbow Trout,Oncorhynchus mykiss          下载免费PDF全文

Gülşen Uluköy  Esİn Baba  Canan Öntaş 《Journal of the World Aquaculture Society》2016,47(5):676-684

The current study investigated the effects of oyster mushroom Pleurotus ostreatus, extract on immunological and hematological parameters of rainbow trout, Oncorhynchus mykiss. The fish were fed diets containing 0 (control), 1, and 2% supplementation of the oyster mushroom extract for 6 wk. Blood samples were collected weekly for the first 6 weeks. After 6 wk of feeding, the fish were challenged with Lactococcus garvieae and mortality was recorded. The results of this study showed that feeding rainbow trout an oyster mushroom extract–supplemented diet stimulated phagocytic activity of phagocytic cells, lysozyme activity, and myeloperoxidase activity in serum, but it did not significantly affect the total serum immunoglobulin level. At the same time, a significant increase was found in the number of neutrophils, monocytes, and total white blood cells. Fish fed the diet supplemented with oyster mushroom extract showed reduced mortalities following L. garvieae infection compared with controls. These results show that supplementation of fish diets with oyster mushroom extract at 1 and 2% concentrations significantly imrpoves hematological parameters and modulates the immune response against L. garvieae in rainbow trout.  相似文献   

Trend analysis of Trichinella in a red fox population from a low endemic area using a validated artificial digestion and sequential sieving technique     

Frits Franssen  Gunita Deksne  Zanda Esíte  Arie Havelaar  Arno Swart  Joke van der Giessen 《Veterinary research》2014,45(1)

Freezing of fox carcasses to minimize professional hazard of infection with Echinococcus multilocularis is recommended in endemic areas, but this could influence the detection of Trichinella larvae in the same host species. A method based on artificial digestion of frozen fox muscle, combined with larva isolation by a sequential sieving method (SSM), was validated using naturally infected foxes from Latvia. The validated SSM was used to detect dead Trichinella muscle larvae (ML) in frozen muscle samples of 369 red foxes from the Netherlands, of which one fox was positive (0.067 larvae per gram). This result was compared with historical Trichinella findings in Dutch red foxes. Molecular analysis using 5S PCR showed that both T. britovi and T. nativa were present in the Latvian foxes, without mixed infections. Of 96 non-frozen T. britovi ML, 94% was successfully sequenced, whereas this was the case for only 8.3% of 72 frozen T. britovi ML. The single Trichinella sp. larva that was recovered from the positive Dutch fox did not yield PCR product, probably due to severe freeze-damage. In conclusion, the SSM presented in this study is a fast and effective method to detect dead Trichinella larvae in frozen meat. We showed that the Trichinella prevalence in Dutch red fox was 0.27% (95% CI 0.065-1.5%), in contrast to 3.9% in the same study area fifteen years ago. Moreover, this study demonstrated that the efficacy of 5S PCR for identification of Trichinella britovi single larvae from frozen meat is not more than 8.3%.  相似文献   

Induction and characterization of monoclonal anti-idiotypic antibodies reactive with idiotopes of canine parvovirus neutralizing monoclonal antibodies.     

G F Rimmelzwaan  J H van Es  G Drost  F G UytdeHaag  A D Osterhaus 《Veterinary immunology and immunopathology》1991,29(1-2):139-150

Monoclonal anti-idiotypic (anti-Id) antibodies (Ab2) were generated against idiotypes (Id) of canine parvovirus (CPV) specific monoclonal antibodies (MoAbs). The binding of most of these anti-Id antibodies to their corresponding Id could be inhibited by antigen, thus classifying these anti-Id antibodies as Ab2 gamma or Ab2 beta. By inhibiting experiments it was shown that these anti-Id antibodies did not recognize interspecies cross-reactive idiotopes, but recognized private idiotopes, uniquely associated with the Id of the anti-CPV MoAb used for immunization. This classifies these anti-Id antibodies as non-internal image Ab2 gamma. The potential use of these non-internal image anti-Id antibodies for the induction of antiviral antibodies in the CPV system is discussed.  相似文献   

Rainfall and tillage effects on soil structure after alfalfa conversion to maize on a clay loam soil in New York     

U. P. Karunatilake  H. M. van Es   《Soil & Tillage Research》2002,67(2)

Soil degradation is accelerated when perennial crops are converted to annual row crops, primarily due to increased soil disturbance from tillage. Subsequent heavy rainfall may induce soil settling, reduce macroporosity and increase hardsetting upon drying. An experiment involving plow and no-tillage and two simulated rainfall treatments (‘wet’ and ‘dry’) was conducted on Kingsbury clay loam soil in northern New York in 1992 and 1993 to study their effects on soil structure under maize (Zea mays L.) after conversion from alfalfa (Medicago sativa L.), and to evaluate the use of spectral analysis of micropenetrometer observations for studying soil aggregation. Undisturbed soil cores were collected from the row and trafficked and non-trafficked interrow positions at the 0.05 and 0.15 m depths and used for laboratory measurement of soil strength and pore system properties. These well-structured soils show a high contribution (up to 0.15 m³ m⁻³) of macropores to the total porosity of the soil. Soil strength was generally slightly higher for no-till (NT) than plow till (PT), although only significant in 1992. Soil strength in the surface layer did not change significantly with drying. Spectral density patterns did not show strong treatment effects, although distinct peaks reflect 3.0–3.5 mm stable structural units within macroaggregates. Simulated rainfall treatments and tillage treatments generally did not strongly affect measured soil properties, presumably due to stable soil structure. Structurally stable clay loam soils show little effect of tillage or settling on soil physical properties in the first years after alfalfa to maize conversion, and have good potential for long-term annual crop production if properly managed.  相似文献   

Soil Test,Aerial Image and Yield Data as Inputs for Site-specific Fertility and Hybrid Management Under Maize     

Antoni Magri  Harold M. Van Es  Michael A. Glos  William J. Cox 《Precision Agriculture》2005,6(1):87-110

Several potential sources of information exist to support precision management of crop inputs. This study evaluated soil test data, bare-soil remote sensing imagery and yield monitor information for their potential contributions to precision management of maize (Zea mays L.). Data were collected from five farmer-managed fields in Central New York in 1999, 2000, and 2001. Geostatistical techniques were used to analyze the spatial structure of soil fertility (pH, P, K, NO₃ and organic matter content) and yield variables (yield, hybrid response and N fertilization response), while remote sensing imagery was processed using principal component analysis. Geographic information system (GIS) spatial data processing and correlation analyses were used to evaluate relationships in the data. Organic matter content, pH, P, and K were highly consistent over time and showed high to moderate levels of spatial autocorrelation, suggesting that grid soil sampling at 2.5–5.5ha scale may be used as a basis for defining fertility management zones. Soil nitrate levels were strongly influenced by seasonal weather conditions and showed low potential for site-specific N management. Aerial image data were correlated to soil organic matter content and in some cases to yield, mainly through the effect of drainage patterns. Aerial image data were not well correlated with soil fertility indicators, and therefore were not useful for defining fertility management zones. Yield response to hybrid selection and nitrogen fertilization rates were highly variable among years, and showed little justification for site-specific management. In conclusion, we recommend grid-based management of lime, P, and K, but no justification existed within our limited study area for site-specific N or hybrid management.  相似文献   

Combined use of hyperspectral VNIR reflectance spectroscopy and kriging to predict soil variables spatially   总被引：1，自引：0，他引：1  

A. Volkan Bilgili  Fevzi Akbas  Harold M. van Es 《Precision Agriculture》2011,12(3):395-420

Hyperspectral visible near infrared reflectance spectroscopy (VNIRRS) and geostatistical methods are considered for precision soil mapping. This study evaluated whether VNIR or geostatistics, or their combined use, could provide efficient approaches for assessing the soil spatially and associated reductions in sample size using soil samples from a 32 ha area (800 × 400 m) in northern Turkey. Soil variables considered were CaCO₃, organic matter, clay, sand and silt contents, pH, electrical conductivity, cation exchange capacity (CEC) and exchangeable cations (Ca, Mg, Na and K). Cross-validation was used to compare the two approaches using all grid data (n = 512), systematic selections of 13, 25 and 50% of the data and random selections of 13 and 25% for calibration; the remaining data were used for validation. Partial least squares regression (PLSR) analysis was used for calibrating soil properties from first derivative VNIR reflectance spectra (VNIRRS), whereas ordinary-, co- and regression-kriging were used for spatial prediction. The VNIRRS-PLSR method provided better prediction results than ordinary kriging for soil organic matter, clay and sand contents, (R ² values of 0.56–0.73, 0.79–0.85, 0.65–0.79, respectively) and smaller root mean squared errors of prediction (values of 2.7–4.1, 37.4–43, 46.9–61, respectively). The EC, pH, Na, K and silt content were predicted poorly by both approaches because either the variables showed little variation or the data were not spatially correlated. Overall, the prediction accuracy of VNIRRS-PLSR was not affected by sample size as much as it was for ordinary kriging. Cokriging (COK) and regression kriging (RK) were applied to a combination of values predicted by VNIR reflectance spectroscopy and measured in the laboratory to improve the accuracy of prediction of the soil properties. The results showed that both COK and RK with VNIRRS estimates improved the predictions of soil variables compared to VNIRRS and OK. The combined use of VNIRRS and multivariate geostatistics results in better spatial prediction of soil properties and enables a reduction in sampling and laboratory analyses.  相似文献   

The influence of growth regulators GA3, ABA,kinetin and IAA on sprout and root growth and plant development using excised potato buds     

K. J. Hartmans  A. Van Es 《Potato Research》1979,22(4):319-332

Summary In a potato bud bioassay GA₃ appeared to stimulate sprout growth and to inhibit root development. The inhibition of root growth retarded the development of the sprouts into plants. Kinetin and IAA stimulated root development. ABA has an initially retarding effect on sprout growth. But during prolongation of the experiment this delay becomes less, and at low concentrations turns into a stimulating effect. During the subsequent development into plants, there is again a stimulating effect of ABA at the higher concentrations.

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Zusammenfassung Pflanzenhormone spielen eine wichtige Rolle in dem Ph?nomen der Keimruhe und der Keimung. Der Einfluss dieser Stoffe auf die Keimung, die Wurzelbildung und die Pflanzenentwicklung wurde mit Hilfe eines bereits früher beschriebenen Biotests mit ausgeschnittenen Augen untersucht (van Es & Hartmans, 1969). In diesem Versuch wurden nur die Seitenknospen nahe des apikalen Auges benutzt, da die Keimf?higkeit von der Lage der Augen auf der Kartoffelknolle abh?ngig ist (Abb. 1). Das wiederum ist eine Folge der unterschiedlichen chemischen Zusammensetzung des die Augen umgebenden Knollengewebes. W?hrend der Keimungsversuche lagen die ausgeschnittenen Augen st?ndig in der Testl?sung. Mit Ausnahme in den Abb. 1, 11 und 12 wurde der Prozentsatz Hemmung oder F?rderung auf die Wasserkontrolle berechnet. Die Keimruhe schien von keiner der getesteten Substanzen beeinflusst zu sein, was durch das Brechen der Keimruhe durch den nach dem Schneiden erh?hten GA-Gehalt verursacht sein kann. Wir fanden, dass der Einfluss auf das Keim- und das Wurzelwachstum entweder hemmend oder f?rdernd war, abh?ngig vom physiologischen Zustand des Materials, der Konzentration der zugesetzen Chemikalien und der Versuchsdauer. Hohe Konzentrationen hemmten das Wachstum, wahrscheinlich ein toxischer Effekt. GA₃, IES und Kinetin f?rderten das L?ngenwachstum der Keime w?hrend ABA hemmte (Abb. 2, 3, 4). Die Hemmung durch ABA nahm jedoch nach wenigen Tagen ab und in geringen Konzentrationen trat sogar eine f?rdernde Wirkung auf (Abb. 5), vielleicht verursacht durch eine Induktion der GA-Synthese durch ABA. Die Wurzelbildung wurde durch GA₃, gehemmt (Abb. 7) und stark gef?rdert durch IES und Kinetin in geringen Konzentrationen (Abb. 8 und 9). ABA hemmte die Wurzelbildung bei hohen und niedrigen Konzentrationen (Abb. 10). Der letztere Effekt kann durch einen Anstieg des GA-Gehaltes verursacht sein, induziert durch ABA. der über die ABA letztlich dominiert. Pflanzen, entstanden aus mit GA₃ behandelten Augen, wuchsen langsam (Abb. 11b), eine Folge der verz?gerten Wurzelentwicklung. Andererseits zeigte mit ABA behandeltes Material ein beschleunigtes Wachstum, das mit den zugeführten Konzentrationen positiv korreliert war (Abb. 12b). Dieser Effekt ist auch durch eine von ABA induzierte Aktivit?t der GA verursacht und ist offensichtlich ein indirekter Effekt.

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Résumé Les hormones des plants jouent un r?le important en ce qui concerne les phénomènes de dormance et de germination. Les effets de ces composés sur la germination, la formation des racines et le dévelopement des plantes ont été examinés au préalable par bio-essai sur des bourgeons excisés (van Es & Hartmans, 1969). Dans cette expérimentation, seuls les bourgeons latéraux situés près du bourgeon apical ont été utilisés, puisque la capacité de germination est dépendante de la localisation des bourgeons sur le tubercule (fig. 1). Ceci est une conséquence de la différence de composition chimique des tissus, environnant les bourgeons. Durant les essais sur la germination, les bourgeons excisés étaient continuellement en contact avec la solution test. Les pourcentages d'inhibition ou de stimulation, (sauf pour les fig. 1, 11 et 12) ont été calculés par rapport au témoin eau. Aucun des composés expérimentés n'a semblé avoir une influence quelconque sur la dormance, laquelle pouvait être due à la rupture de dormance occasionnée par exemple par l'augmentation du taux d'acide gibberellique après blessure. Dépendamment de l'état physiologique du matériel, de la concentration des produits chimiques appliqués et de la durée de l'expérimentation, nous avons, trouvé que l'effet sur la croissance des germes et celle des racines était soit inhibiteur, soit stimulateur. De hautes concentrations ont inhibé la croissance, probablement est-ce le résultat des effets toxiques. L'acide gibberellique, l'acide indol-acétique et la kinétine ont favorisé l'élongation des germes tandis que l'acide abscissique l'a inhibé (fig. 2, 3 et 4). Cependant, l'inhibition due à l'acide abscissique déclinait après quelques jours et pouvait même se transformer en stimulation à basse concentration (fig. 5): peut-être était-ce d? à la synthèse de l'acide gibberellique induite par l'acide abscissique. La formation des racines était inhibée par l'acide gibberellique (fig. 7) et fortement stimuléc par l'acide indol-acétique et la kinétine à basse concentration (fig. 8 et 9). Les plantes issues de bourgeons excisés traités à l'acide gibberellique poussaient lentement (fig. 11b) en conséquence du développement retardé des racines. Le matériel traité à l'acide abscissique présentait une croissance accélérée qui était positivement en corrélation avee les concentrations appliquées (fig. 12b). Cet effet est aussi attribué à l'acide abscissique induit, à l'activité de l'acide gibberellique et est manifestement un effet indirect.

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GA₃=gibberellic acid; ABA=abscisic, acid; IAA=indolacetic acid; kinetin=6-furfuryl-amino-purine.  相似文献   

Changes in the content of L-ascorbic acid,glucose, fructose,sucrose and total glycoalkaloids in potatoes (cv. Bintje) stored at 7, 16 and 28°C     

Anita R. Linnemann  André van Es  Klaasje J. Hartmans 《Potato Research》1985,28(3):271-278

Summary We investigated the changes in the content of L-ascorbic acid (L-AA), glucose, fructose, surose and total glycoalkaloids (TGA) during storage of potatoes, cv. Bintje, for 12 weeks at 7,16 and 28°C. The initial amount of L-AA was 8.2 mg/100g fresh weight; after 12 weeks' storage at 7°C it had decreased, while at 16 and 28°C it had increased. The sugar content went up most in potatoes stored at 28°C, but remained below the level at which potatoes taste sweet. The sugar content rose slightly at 16°C, while it decreased in tubers stored at 7°C. The initial TGA content, in equivalent amounts of α-solanine, was 3.6 mg/100 g fresh weight; after 12 weeks' storage it had decreased slightly at all three storage temperatures.  相似文献   

Intratumoral injection of radioactive holmium ( 166Ho) microspheres for treatment of oral squamous cell carcinoma in cats          下载免费PDF全文

S. A. van Nimwegen  R. C. Bakker  J. Kirpensteijn  R. J. J. van Es  R. Koole  M. G. E. H. Lam  J. W. Hesselink  J. F. W. Nijsen 《Veterinary and comparative oncology》2018,16(1):114-124

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