29 results on '"Mastenbroek N"'
Search Results
2. Burnout and engagement, and its predictors in young veterinary professionals: the influence of gender
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Mastenbroek, N. J. J. M., Jaarsma, A. D. C., Demerouti, E., Muijtjens, A. M. M., Scherpbier, A. J. J. A., and van Beukelen, P.
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- 2014
- Full Text
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3. Measurement of vessel traffic service operator performance
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Wiersma, E. and Mastenbroek, N.
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- 1998
- Full Text
- View/download PDF
4. Persoonlijke hulpbronnen om te komen tot succes
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't Mannetje, Jolise, Heijne-Penninga, Marjolein, Mastenbroek, N., Gellevij, M., Wolfensberger, Marca, Jaarsma, Debbie, and Talentontwikkeling in Hoger Onderwijs en Samenleving
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honors education ,honoursonderwijs - Published
- 2017
5. Studies on Bovine Leukaemia
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J. Quak, A. A. Ressang, Van Der Maaten Mj, Miller Jm, Ellens Dj, and Mastenbroek N
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Bovine leukaemia ,Biology ,Virology ,Serology - Published
- 2010
6. Studies on Bovine Leukaemia
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A. A. Ressang, J. Quak, J. C. Baars, Jero Calafat, and Mastenbroek N
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Micro complement fixation ,Precipitating antibodies ,Indirect Fluorescent Antibody Technique ,Bovine leukaemia ,Biology ,Serum samples ,Molecular biology ,Virus ,Leucosis ,Serology - Abstract
Summary A total of 516 animals including cows, sheep and goats from 2 experimental stations, 3 farms and from the Central Veterinary Institute, Rotterdam, were examined haematologically for the presence of (persistent) lymphocytosis, serologically for antibodies to bovine leukaemia virus (BLV), virologically for BL antigen and electron microscopically for BLV particles. The serological methods used were the indirect fluorescent antibody technique (ID FAT), the indirect immunoperoxidase test (ID IPT), the micro complement fixation test (M CFT) and the gel diffusion test (GDT). In addition 297 serum specimens from Copenhagen, Weybridge and Belfast were examined serologically. Haematology was performed by the donating Institutes. It is concluded that: 1 Haematological diagnosis of BL has serious restrictions in that Iymphocytosis occurs late in the course of disease. 2 For the early diagnosis of BL serological examinations are the methods of choice. 3 The antibodies detected were specific as supported by virological and EM work. 4 In the 516 selected Dutch animals only 3.9% showed lymphocytosis as opposed to 13% which had fluorescing, 11.2% with peroxidase linking, 9% with complement fixing and 8.5% with precipitating antibodies to BLV. 5 In the Danish samples 17 sera taken from 19 cows with lymphocytosis contained fluorescent antibodies; the 18th FA positive serum was from an animal with normal blood counts. Peroxidase linking antibodies were found in 17 and precipitating antibodies were seen in 11 of these 19 sera. No antibodies to BLV were found in the 200 serum samples from Weybridge and Belfast including the 2 calves with sporadic juvenile leukosis. Zusammenfassung Untersuchungen uber die Rinderleukose II. Hamatologische, serologische, virologische und elektronenmikroskopische Diagnose 516 Tiere (Kuhe, Schafe, Ziegen) aus den Niederlanden sind hamatologisch auf das Vorliegen einer (persistierenden) Lymphozytose, sowie auf das Vorkommen von Antikorpern gegen bovinem Leukosevirus und das Vorkommen von Leukosevirus-Antigen und Leukosevirus-Partikeln untersucht worden. Weitere 297 Seren aus Danemark und Grosbritannien wurden serologisch untersucht. Aus den Untersuchungsergebnissen werden folgende Schlusfolgerungen gezogen: 1 Der Wert einer hamatologischen Diagnose der Rinderleukose wird dadurch beeintrachtigt, das die Lymphozytose erst im fortgeschrittenen Krankheitsstadium auftritt. 2 Fur die Fruhdiagnose der Rinderleukose sind serologische Untersuchungsmethoden am geeignetsten. 3 Die Spezifitat der Leukosevirus-Antikorper wurde durch die Ergebnisse virologischer und elektronenmikroskopischer Untersuchungen bestatigt. 4 Von 516 niederlandischen Tieren hatten 3,9% eine Lymphozytose; 13% hatten fluoreszierende, 11,2% peroxydasebindende, 9% komplementbindende und 8,5% prazipitierende Antikorper gegen Leukosevirus. 5 Von 19 danischen Kuhen mit Lymphozytose hatten 17 fluoreszierende, 17 peroxydasebindende und 11 prazipitierende Antikorper. In 200 Seren aus Grosbritannien konnten keine Antikorper gegen Rinderleukose-Virus nachgewiesen werden. Resume Recherches sur la leucose bovine II. Diagnostic hematologique, serologique, virologique et en microscopie electronique On a recherche hematologiquement l'existence de lymphocytose (persistante) ainsi que la presence d'anticorps contre le virus de la leucose bovine, d'antigene viral et de particules virales chez 516 animaux (vaches, moutons, chevres) en provenance des Pays-Bas. 297 autres serums provenant du Danemark et de Grande-Bretagne ont ete examines serologiquement. Les resultats suivants sont apparus: 1 La valeur d'un diagnostic hematologique de la leucose bovine est influencee par le fait que la lymphocytose n'apparait qu'au stade avance de la maladie. 2 Les methodes d'investigation serologiques sont les plus indiquees pour le diagnostic precoce de la leucose bovine. 3 La specificite des anticorps contre le virus de la leucose fut confirmee par les resultats des recherches virologiques et au microscope electronique. 4 Le 3,9 % sur 516 animaux des Pays-Bas presenta une lymphocytose; 13% avait des anticorps fluorescents, 11,2% des anticorps liant la peroxydase, 9% des anticorps fixant du complement et 8,5% des anticorps precipitants contre le virus de la leucose. 5 Sur 17 vaches danoises atteintes de leucose, 17 presenterent des anticorps fluorescents, 17 des anticorps liant la peroxydase et 11 des anticorps precipitants. Aucun des 200 serums provenant de Grande-Bretagne ne presenta des anticorps contre le virus de la leucose bovine. Resumen Estudios sobre la leucosis bovina II. Diagnostico hematologico, serologico, virologico y electronicomicroscopico Se examinaron hematologicamente 516 animales (vacas, ovejas, cabras) de los Paises Bajos en cuanto a la presencia de una linfocitosis (persistente), asi como en cuanto a la presencia de anticuerpos frente al virus de leucosis bovina y la presencia de antigeno y particulas de virus de leucosis. Se examinaron serologicamente otros 297 sueros sanguineos mas procedentes de Dinamarca y Gran Bretana. De los resultados de examen se sacan las consecuencias siguientes: 1 El valor de un diagnostico hematologico de leucosis bovina se ve amenguado por el hecho de que la linfocitosis aparece solo en el estadio avanlado de enfermedad. 2 Lo mas apropiado para el diagnostico precoz de leucosis bovina son los metodos serologicos. 3 La especificidad de los anticuerpos frente al virus de leucosis se conformo mediante los resultados de investigacion virologica y electronicomicroscopica. 4 Entre 516 animales neerlandeses tenia el 3,9% una linfocitosis; 13% tenia anticuerpos fluorescentes frente al virus de leucosis, 11,2% fijadores de peroxidasa, 9% fijadores del complemento y 8,5% precipitantes. 5 Entre 19 vacas danesas con linfocitosis tenian 17 anticuerpos fluorescentes, 17 anticuerpos fijadores de peroxidasa y 11 idem precipitantes. En 200 sueros sanguineos de Gran Bretana no se pudieron identificar anticuerpos frente al virus de leucosis bovina.
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- 2010
7. Studies on Bovine Leucosis IX. Excretion of Bovine Leucosis Virus
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Mastenbroek N, J. Quak, and A. A. Ressang
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Male ,Leukemia ,Leukemia, Experimental ,Sheep ,Cattle Diseases ,Urine ,Biology ,Molecular biology ,Virus ,Leucosis ,Excretion ,Feces ,Tumor Virus Infections ,Retroviridae ,Leukemia Virus, Bovine ,Animals ,Cattle ,Female ,Saliva - Abstract
Summary Excretion of bovine leucosis virus (BLV) in cattle affected with enzootic bovine leucosis was examined by contact exposure and by the inoculation of saliva, urine and faecal material using three-months-old sheep and newborn lambs. Only 5 of 17 cattle had BLV in their saliva. Of these, two were detected by the inoculation of newborn lambs. All sheep and lambs injected with urine and faecal material were serologically negative for antibodies to BLV throughout an observation period of two years. Of the sheep exposed to contact infection none had antibody to BLV over an observation period of two years. One of the four calves exposed in parallel to contact infection had serum antibodies to BLV three months after onset of the experiment. The authors conclude that faeces and urine from infected cattle are insignificant as sources of infection with BLV. Viral transmission via saliva is possible, although the number of cattle with BLV in their saliva is low. It is thus sufficient to strictly separate infected animals from healthy ones so as to prevent spread by contact (droplet) infection. Emphasis must be put on infection via colostrum, milk, needles and other instruments and by blood, sucking vectors. Zusammenfassung Untersuchungen uber Rinderleukose IX. Ausscheidung von Rinderleukose-Virus Die Ausscheidung des bovinen Leukosevirus (BLV) von enzootisch mit boviner Leukose infizierten Rindern wurde uber Kontaktexposition und durch Uberimpfung von Speichel, Urin und Faecesmaterial auf drei Monate alte Schafe und neugeborene Lammer untersucht. Nur bei funf von siebzehn Rindern konnte BLV im Speichel nachgewiesen werden. Von diesen wurden zwei durch Inokulation neugeborener Lammer festgestellt. Alle Schafe und Lammer, denen Urin und Faecesmaterial uberimpft worden war, zeigten sich uber einen Beobachtungszeitraum von zwei Jahren serologisch negativ bezuglich Antikorper gegen BLV. Unter den Schafen, die der Kontaktinfektion ausgesetzt waren, hatte kein Tier Antikorper gegen BLV nach einer Beobachtungszeit von zwei Jahren entwickelt. Eines der vier Kalber, bei denen zur gleichen Zeit die Infektionsmoglichkeit durch Kontakt gegeben war, hatte Serum-Anti-korper gegen BLV drei Monate nach Versuchsbeginn gebildet. Die Autoren ziehen den Schlus, das Faeces und Urin infizierter Rinder als Ansteckungsquelle fur BLV keine Bedeutung haben. Eine Virusubertragung durch den Speichel wird als moglich erachtet, obwohl die Zahl der Rinder mit BLV im Speichel gering ist. Dies genugt dennoch, infizierte Tiere von gesunden konsequent abzusondern, um die Ausbreitung der Infektion durch Kontakt (Tropfcheninfektion) zu verhindern. Hervorgehoben sei die Infektionsmoglichkeit via Kollostrum, Milch, Injektionsnadeln sowie andere Instrumente, und, als Variante von letzterem, durch blutsaugende Vektoren. Resume Recherches sur la leucose bovine IX. Excretion du virus de la leucose bovine L'excretion du virus de la leucose bovine (BLV) chez des bovins infectes enzootiquement a ete examinee par exposition de contact et par injection de salive, d'urine et de matieres fecales sur des agneaux de 3 mois et des agneaux nouveau-nes. BLV a ete mis en evidence dans la salive de seulement 5 des 17 bovins. Deux ont ete etablis par inoculation chez des agneaux nouveaunes. Tous les moutons et les agneaux avec passage par injection d'urine et de matieres fecales n'ont pas montre serologiquement d'anticorps anti-BLV apres un temps d'observation de deux ans. Les moutons exposes a une infection par contact n'ont pas developpe d'anticorps anti-BLV apres une periode d'observation de deux ans. Un des quatre veaux ayant pu etre infecte par contact au meme moment avait forme des anticorps seriques anti-BLV trois mois apres le debut de l'essai. Les auteurs estiment que les matieres fecales et l'urine de bovins infectes n'ont pas de signification en tant que source d'infection pour BLV. Une transmission virale avec la salive est possible, bien que le nombre des bovins avec de la salive contenant BLV soit faible. Cela est toutefois suffisant pour separer les animaux infectes des animaux sains pour empecher l'extension de l'infection par contact (infection par gouttelettes). On releve la possibilite d'une infection par le colostrum, le lait, avec des aiguilles a injection et d'autres instruments et par analogie avec des vecturs suceurs de sang. Resumen Estudios sobre la leucosis bovina IX. Excrecion del virus de la leucosis bovina Se examino la excrecion del virus de la leucosis bovina (BLV) de vacunos infectados enzooticamente con leucosis bovina a traves de la exposicion de contacto y mediante la inoculacion de saliva, orina y material fecal a ovejas de tres meses de edad y corderos recien nacidos. Solo en cinco entre diecisiete vacunos se pudo identificar BLV en la saliva. Dos de ellos se detectaron por medio de la inoculacion de corderos recien nacidos. Todas las ovejas y corderos, a las que se habia inoculado orina y material fecal, se mostraron negativas serologicamente con respecto a los anticuerpos anti BLV a lo largo de un periodo de observacion de dos anos. Entre las ovejas que habian estado expuestas a la infeccion de contacto, ningun animal desarrollo anticuerpos anti BLV tras un espacio de tiempo de observacion de dos anos. Una de las cuatro terneras, en las que en el mismo tiempo hubo la ocasion de infeccion por contacto, formo anticuerpos anti BLV tres meses despues de comenzar el ensayo. Los autores llegan a la conclusion que las heces y la orina de los vacunos infectados no juegan ningun papel como fuente de contagio del virus BLV. La transmision del virus a traves de la saliva se considera como posible, aunque es escasa la cantidad de vacunos con BLV en la saliva. Sin embargo, esto es suficiente para poder separar consecuentemente los animales enfermos de los sanos, impidiendo la difusion de la infeccion por contacto (infeccion por gotitas). Se destaca la posibilidad de la infeccion via calostro, leche, agujas hipodermicas y otros instrumentos y, como variante de esto ultimo, mediante vectores chupadores de sangre.
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- 2010
8. Studies on Bovine Leukemia
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T. Souissi, Sietske Swen, Jero Calafat, Jo Hilgers, A. A. Ressang, J. Quak, Philomena C. Hageman, Mastenbroek N, and L. J. L. D. van Griensven
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Cell culture ,viruses ,Immunology ,Biology ,Bovine Leukemia ,Molecular biology ,Virus - Abstract
Summary The fluorescent antibody technique and the immunodiffusion test were used for the serological detection of type C virus found in one bovine and two sheep established cell lines. The electron microscopic demonstration of type C virus particles supported by uridine labelling suggested that a virus specific antigen underlay the FA reaction and the reaction of identity in the IDT. Preliminary FA tests employing various antisera against mammalian oncornaviruses may indicate that bovine leukemia virus represents antigenically a unique group. Zusammenfassung Untersuchungen uber die Rinderleukose I. Gewinnung von C-Typ virusproduzierenden Zell-Linien Leukozyten einer Leukose-kranken Kuh und Lymphknoten-explantate von zwei Leukose-infizierten Schafen dienten zur Gewinnung permanenter Zell-Linien. In diesen Zellkulturen konnten C-Typ Virus und Virusantigen elektronenoptisch, fluoreszenzserologisch, mittels Immunodiffusion und durch Markierung mit 3H-Uridin nachgewiesen werden. Vergleichende fluoreszenzserologische Untersuchungen mit Seren gegen eine Reihe von Oncornaviren anderer Saugetiere deuten darauf hin, das das Virus der Rinderleukose eine antigen selbstandige Untergruppe der Oncornaviren darstellt. Resume Recherches sur la leucose bovine I. Obtention des lignees cellulaires produisant du virus type C Des leucocytes d'une vache atteinte de leucose et des explantats de ganglions de deux moustons infectes de leucose ont servi a obtenir les lignees cellulaires permanentes. On a pu mettre en evidence dans ces cultures cellulaires un virus du type C et un antigene viral au microscope electronique, par l'immunofluorescence, au moyen de l'immunodiffusion et par marquage avec 3H-uridine. Des recherches comparees en fluorescence avec des antiserums d'une serie d'oncornavirus d'autres mammiferes ont montre que le virus de la leucose bovine represente un sous-groupe antigeniquement unique. Resumen Estudios sobre la leucosis bovina I. Obtencion de lineas celulares que producen el virus tipo C Los leucocitos de una vaca leucotica y las explantaciones ganglionares de dos ovejas infectadas con leucosis se utilizaron para obtener lineas celulares permanentes. En estos cultivos celulares se identificaron particulas virales del tipo C con la ayuda del microscopio electronico y del marcaje con uridina-3H. Se detectaron tambien antigenos virales con las tecnicas de immunofluorescencia e imunodifusion. Los estudios fluorescenteserologicos comparativos realizados con sueros contra una serie de virus oncorna de otros mamiferos parecen indicar que el virus de la leucosis pertenece a un subgrupo antigenicamente independiente de los virus oncorna.
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- 2010
9. The role of personal resources in explaining well-being and performance: A study among young veterinary professionals
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Mastenbroek, N. J. J. M., Jaarsma, A. D. C., Scherpbier, A. J. J. A., van Beukelen, P., Demerouti, E., Jaarsma, Debbie, Onderwijs instituut FHML, RS: SHE - R1 - Research (OvO), Human Performance Management, and Center for Evidence Based Education
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ORGANIZATIONAL-BEHAVIOR ,Organizational Behavior and Human Resource Management ,Veterinary medicine ,Exhaustion ,Performance ,OBJECTIVE PERFORMANCE ,Well-being ,PREDICT BURNOUT ,Job Demands-Resources model ,TASK-PERFORMANCE ,METAANALYSIS ,Applied Psychology ,Self-efficacy ,Contextual performance ,CONTEXTUAL PERFORMANCE ,Work engagement ,SELF-EFFICACY ,FRAMEWORK ,Job demands-resources model ,JOB DEMANDS ,Job performance ,Organizational behavior ,Job analysis ,Personal resources ,Psychology ,Social psychology - Abstract
This study examines the role of three personal resources (i.e., proactive behaviour, reflective behaviour, and self-efficacy) in the Job Demands-Resources (JD-R) model in order to predict self and other ratings of performance. The sample consisted of 860 Dutch veterinary professionals and 170 colleagues. We hypothesized and found that work engagement mediates the relationship between job as well as personal resources and extrarole performance and the relationship between job resources and work engagement. Although hypothesized, we found no support for the mediating role of exhaustion in the relationship between job demands as well as personal resources and inrole performance. Moreover personal resources were directly related to in- and extrarole performance. In conclusion, the study expands the JD-R model by integrating personal resources at a behavioural level and performance measures in the model, and shows that personal resources have a mediating and initiating role in explaining work engagement and performance in young veterinary professionals.
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- 2014
10. Effects of a 1 year development programme for recently graduated veterinary professionals on personal and job resources: a combined quantitative and qualitative approach
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Mastenbroek, N. J. J. M., primary, van Beukelen, P., additional, Demerouti, E., additional, Scherpbier, A. J. J. A., additional, and Jaarsma, A. D. C., additional
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- 2015
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11. The role of personal resources in explaining well-being and performance: A study among young veterinary professionals
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Mastenbroek, N. J. J. M., primary, Jaarsma, A. D. C., additional, Scherpbier, A. J. J. A., additional, van Beukelen, P., additional, and Demerouti, E., additional
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- 2012
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12. Measurement of Vessel Traffic Service Operator Performance
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Wiersma, E., primary and Mastenbroek, N., additional
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- 1997
- Full Text
- View/download PDF
13. Eenige opmerkingen aangaande Menbranipora crustulenta (Pallas)
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Mastenbroek, N. and Naturalis journals & series
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In het brakke water van de Zeeuwsche eilanden komen Bryozoën voor, die tot het geslacht Membranipora behooren en die zich van de andere soorten van dit geslacht onderscheiden door den vorm van de kolonie. De dieren liggen hier niet, zooals bij de meeste Membranipora's, tegen het substraat aan, maar vormen afstaande korsten, die tot groote, samengestelde klompen kunnen uitgroeien en die zich vasthechten aan palen en bruggen. Deze Bryozoën zijn door een aantal onderzoekers, die ze tot zeer verschillende soorten brachten, in Zeeland en het omgevende gebied gevonden. In „Flora en Fauna der Zuiderzee" vermeldt Mej. van Benthem Jutting (1922) dezen vorm als Membranipora membranacea (L.) var. erecta Loppens, naar aanleiding van de determinate van overeenkomstige Bryozoënkolonies door Loppens (1906) als bovengenoemde variëteit. De door Loppens beschreven kolonies komen inderdaad geheel overeen met den vorm, die in brakke wateren voorkomt als broze kluiten van sintelachtige consistentie, waarvan van der Sleen (1918), die ook Loppens aanhaalt, melding maakt. Van het voorkomen van den bewusten vorm was reeds eerder een mededeeling gedaan door Maitland (1896). Hij rekent deze dieren nu tot een variëteit van Flustra johnstoni, een soort, die volgens Maitland veelvuldig op schelpen en steenen der Zeeuwsche stroomen voorkomt. Deze Flustra johnstoni is nu identiek met een door Johnston (1847) beschreven vorm van Membranipora membranacea (Johnston, I.c., p. 328, Pl. LVI, fig. 7). In hetzelfde werk geeft hij op PI. LVII, fig. 11 en 12 twee vrij nauwkeurige teekeningen, waaruit met zekerheid te concludeeren is, dat deze gemaakt zijn naar objecten, die identiek zijn met de in brakwater voor
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- 1927
14. Eenige opmerkingen aangaande Menbranipora crustulenta (Pallas)
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Mastenbroek, N. van and Mastenbroek, N. van
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In het brakke water van de Zeeuwsche eilanden komen Bryozoën voor, die tot het geslacht Membranipora behooren en die zich van de andere soorten van dit geslacht onderscheiden door den vorm van de kolonie. De dieren liggen hier niet, zooals bij de meeste Membranipora's, tegen het substraat aan, maar vormen afstaande korsten, die tot groote, samengestelde klompen kunnen uitgroeien en die zich vasthechten aan palen en bruggen. Deze Bryozoën zijn door een aantal onderzoekers, die ze tot zeer verschillende soorten brachten, in Zeeland en het omgevende gebied gevonden. In „Flora en Fauna der Zuiderzee" vermeldt Mej. van Benthem Jutting (1922) dezen vorm als Membranipora membranacea (L.) var. erecta Loppens, naar aanleiding van de determinate van overeenkomstige Bryozoënkolonies door Loppens (1906) als bovengenoemde variëteit. De door Loppens beschreven kolonies komen inderdaad geheel overeen met den vorm, die in brakke wateren voorkomt als broze kluiten van sintelachtige consistentie, waarvan van der Sleen (1918), die ook Loppens aanhaalt, melding maakt. Van het voorkomen van den bewusten vorm was reeds eerder een mededeeling gedaan door Maitland (1896). Hij rekent deze dieren nu tot een variëteit van Flustra johnstoni, een soort, die volgens Maitland veelvuldig op schelpen en steenen der Zeeuwsche stroomen voorkomt. Deze Flustra johnstoni is nu identiek met een door Johnston (1847) beschreven vorm van Membranipora membranacea (Johnston, I.c., p. 328, Pl. LVI, fig. 7). In hetzelfde werk geeft hij op PI. LVII, fig. 11 en 12 twee vrij nauwkeurige teekeningen, waaruit met zekerheid te concludeeren is, dat deze gemaakt zijn naar objecten, die identiek zijn met de in brakwater voor
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- 1927
15. Control of Marek's Disease in the Netherlands. I. Isolation of an Avirulent Marek's Disease Virus (Strain CVI 988) and Its Use in Laboratory Vaccination Trials
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Schat Ka, Mastenbroek N, Rispens Bh, van Vloten H, and Maas Hj
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Marek's disease ,animal structures ,General Immunology and Microbiology ,biology ,Marek Disease Vaccines ,Mardivirus ,Viremia ,biology.organism_classification ,medicine.disease ,Virology ,Virus ,Vaccination ,Food Animals ,Immunity ,medicine ,Animal Science and Zoology ,Seroconversion - Abstract
A Marek's disease virus of low pathogenicity was isolated from a flock of chickens and was designated strain CVI 988. On primary isolation, this virus did not cause disease in susceptible chicks and gave excellent protection on subsequent challenge with a virulent virus, even if this challenge was performed shortly after vaccination. The virus occasionally caused minor microscopic lesions in antibody-free MD susceptible chicks but on further passage in DEF cultures the virus became completely avirulent while retaining its A antigen, spreading capacity and immunizing potentials. Chicks vaccinated by contact exposure developed a high degree of MD resistance after the 5th week but immunity was induced more rapidly when 3-week-old seeder chicks, which were actively shedding vaccine virus, were used as the source of exposure. However, by any procedure, contact-vaccinated chicks required several weeks for the development of solid immunity. High passage virus did not become virulent after 5 subsequent passages in antibody-free MD susceptible chicks. Vaccinated birds produced antibody which remained at a high level through observation periods of 2 years. Viremia and virus-shedding persisted throughout this period in a considerable number of birds. Rhesus monkeys inoculated with the virus did not develop any lesions during a one year observation period and no seroconversion could be detected.
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- 1972
16. Control of Marek's Disease in the Netherlands. II. Field Trials on Vaccination with an Avirulent Strain (CVI 988) of Marek's Disease Virus
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Maas Jl, Schat Ka, Rispens Bh, Mastenbroek N, and van Vloten H
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Vaccination ,Marek's disease ,General Immunology and Microbiology ,Food Animals ,biology ,Immunology ,Avirulent strain ,Animal Science and Zoology ,biology.organism_classification ,Virology ,Virus - Published
- 1972
17. [Research quality of life for young veterinarians].
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Mastenbroek N
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- Curriculum, Humans, Sick Leave, Work Schedule Tolerance, Workload, Education, Veterinary standards, Professional Competence standards, Quality of Life, Veterinarians psychology
- Published
- 2009
18. Studies on bovine leukosis. VI. Enzyme linked immunosorbent assay for the detection of antibodies to bovine leukosis virus.
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Ressang AA, Gielkens AL, Quak S, Mastenbroek N, Tuppert C, and De Castro A
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- Animals, Cattle immunology, Female, Immunodiffusion, Leukemia diagnosis, Antibodies, Viral analysis, Cattle Diseases diagnosis, Enzyme-Linked Immunosorbent Assay, Immunoenzyme Techniques, Leukemia veterinary, Leukemia Virus, Bovine immunology, Retroviridae immunology
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The results of examination of 2 784 sera in the AGIDT-gp were compared with those of the ELISA. A discrepancy was seen in 0.5% of the cases. It was concluded that the ELISA was another useful serological method added to the list of serological techniques presently available for the detection of antibodies to BLV. The advantages of the technique are discussed.
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- 1978
19. [Bovine leukaemia. Recent views on aetiology and diagnosis (author's transl)].
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Ressang AA, Mastenbroek N, and Quak J
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- Animals, Antigens, Viral, Cattle, Fetus, Fluorescent Antibody Technique, Leukemia microbiology, Lung immunology, RNA Viruses isolation & purification, Retroviridae isolation & purification, Serologic Tests, Cattle Diseases diagnosis, Leukemia veterinary
- Published
- 1975
20. Studies on bovine leukosis. VII. Further experience with an ELISA for the detection of antibodies to bovine leukosis virus.
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Ressang AA, Gielkens AL, Quak J, and Mastenbroek N
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- Animals, Antibodies, Viral analysis, Cattle, Leukemia diagnosis, Cattle Diseases diagnosis, Enzyme-Linked Immunosorbent Assay, Immunodiffusion, Immunoenzyme Techniques, Leukemia veterinary, Leukemia Virus, Bovine immunology, Retroviridae immunology
- Abstract
An enzyme linked immunosorbent assay (ELISA) and the agar gel immunodiffusion test with bovine leukosis virus glycoprotein as antigen (AGIDT-BLV gp) were further used to test 633 bovine sera for antibodies to BLV. Both tests detected the same number of sera positive (149) or negative (464) for antibodies. Nine sera were negative in the ELISA but found to be weakly positive (2 sera) or bending the control line (7) in the AGDT-BLV gp. On the other hand 11 sera were scored negative in the AGIDT-BLV gp but were weakly positive (9 sera), positive (1), and strongly positive (1) in the ELISA. Both tests are used routinely in this Institute as they complement each other, specially if sera with low antibody titers are under investigation. It is concluded that ELISA can fully replace radioimmunoassays in the serodiagnosis of enzootic bovine leukosis.
- Published
- 1981
- Full Text
- View/download PDF
21. Studies on bovine leukemia. I. Establishment of type C virus producing cell lines.
- Author
-
Ressang AA, Mastenbroek N, Quak J, van Griensven LJ, Calafat J, Hilgers J, Hageman PC, Souissi T, and Swen S
- Subjects
- Animals, Cattle, Cell Line, Cells, Cultured, Female, Fluorescent Antibody Technique veterinary, Leukocytes microbiology, Sheep, Cattle Diseases microbiology, Lymphoma, Non-Hodgkin veterinary, Retroviridae isolation & purification, Sheep Diseases microbiology
- Published
- 1974
22. Studies on bovine leucosis. IX. Excretion of bovine leucosis virus.
- Author
-
Ressang AA, Mastenbroek N, and Quak J
- Subjects
- Animals, Cattle, Cattle Diseases transmission, Feces microbiology, Female, Leukemia microbiology, Leukemia Virus, Bovine pathogenicity, Leukemia, Experimental transmission, Male, Saliva microbiology, Sheep microbiology, Tumor Virus Infections microbiology, Tumor Virus Infections transmission, Tumor Virus Infections veterinary, Urine microbiology, Cattle Diseases microbiology, Leukemia veterinary, Leukemia Virus, Bovine isolation & purification, Retroviridae isolation & purification
- Published
- 1982
- Full Text
- View/download PDF
23. [Transmission and immune response in bovine enzootic leukosis (author's transl)].
- Author
-
Ressang AA, Mastenbroek N, and Quak J
- Subjects
- Animals, Cattle, Cattle Diseases immunology, Female, Immunologic Techniques, Insemination, Artificial veterinary, Leukemia immunology, Leukemia transmission, Male, Cattle Diseases transmission, Leukemia veterinary, Leukemia Virus, Bovine immunology, Retroviridae immunology
- Abstract
The causative agent of enzootic bovine leukosis (EBL) is an oncogenic RNA virus named bonvine leukosis virus (BLV). At present, instead of bovine leukemia, the name bovine leukosis is preferentially used to avoid an erroneous association with leucaemia in man. In all European Community Countries the serological diagnosis of EBL has gradually replaced hematology. A number of these serological techniques are available to-date. In the Central Veterinary Institute in Rotterdam the agar gel immunodiffusion technique, the FAT and the ELISA are used as diagnostical tools. Based on own experiments it is provisionally concluded that BLV shedding via faeces and urine does not occur. Saliva has been found infective in three out of fourteen cases (21 per cent). There is no evidence of transmission of BLV in the sperm. Prostate fluid and sperm from seven experimentally infected bulls did not contain neither BLV antigen nor antibodies to BLV. Five calves born from five cows which had been naturally served by the mentioned bulls did not show sero conversion after an observation period of one year. The authors recommend to use in AI only sperm form bulls which are negative for antibodies to BVL. Preferentially other cattle at the same farm-enterprise should be serologically tested with negative results within three months before shipment of the sperm. The humoral and cellular immunological status of leucotic cattle are examined by the application of pig erythrocytes, tetanus toxoid, Bordetella- and Aujeszky vaccine. The seroloical reactions of leucotic cattle did not differ significantly from those of the "normal' controls. By contrast the cutaneous tuberculine reaction following administration of Mycobacterium microtii was significantly more obvious in the leucotic animals as compared to the controls.
- Published
- 1980
24. Studies on bovine leucosis V. A comparative study on the practical value of the agar gel immunodiffusion test, the indirect fluorescent antibody technique and the micro complement fixation test for the detection of antibodies to bovine leucosis virus.
- Author
-
Ressang AA, Mastenbroek N, and Quak J
- Subjects
- Animals, Cattle, Complement Fixation Tests, Fluorescent Antibody Technique, Immunodiffusion, Leukemia immunology, Antibodies, Viral analysis, Cattle Diseases immunology, Leukemia veterinary, Leukemia Virus, Bovine immunology, Retroviridae immunology
- Abstract
The practical value of the indirect fluorescent antibody technique (I FAT), the micro complement fixation test (M CFT) and the agar gel immunodiffusion test (AGIDT) for the detection of antibodies to bovine leucosis virus (BLV) was investigated. For this purpose 1495 serum samples were examined. There was a remarkably good agreement between the three tests in the demonstration of antibodies to BLV especially if sera with a sufficient high concentration of antibodies ("late serum") were under investigation. These positive sera were derived only from farms which exploited one or more imported animals. A disagreement of results of the three tests was observed in 38 (2.5%) cases. This was due to: (1) difficulties in reading of the test; (2) presumably by the demonstration of different classes of antibody and (3) the fact that in the AGIDT sera could be used undiluted. This discrepancy was especially evident with sera with a low concentration of antibodies ("early or incubation sera"). A drawback for the M CFT is the anticomplementary activity found in 17% of the bovine serum samples.
- Published
- 1978
25. Studies on bovine leukaemia II. Haematological, serological, virological and electron microscopical diagnosis.
- Author
-
Ressang AA, Ellens DJ, Mastenbroek N, Quak J, Miller JM, and Van Der Maaten MJ
- Subjects
- Animals, Antigens, Viral analysis, Cattle, Leukemia diagnosis, Leukemia Virus, Bovine isolation & purification, Leukocyte Count, Microscopy, Electron, Serologic Tests, Cattle Diseases diagnosis, Leukemia veterinary
- Published
- 1976
26. Studies on bovine leukaemia. III. The haematological and serological response of sheep and goats to infection with whole blood from leukaemic cattle.
- Author
-
Ressang AA, Baars JC, Calafat J, Mastenbroek N, and Quak J
- Subjects
- Animals, Cattle, Leukemia immunology, Leukemia Virus, Bovine immunology, Leukocyte Count, Neoplasm Transplantation, Transplantation, Heterologous, Cattle Diseases, Goats immunology, Leukemia veterinary, Sheep immunology
- Published
- 1976
27. [Enzootic bovine leukaemia, diagnosis, distribution and control in the Netherlands (author's transl)].
- Author
-
Ressang AA, Mastenbroek N, and Quak J
- Subjects
- Animals, Antibodies, Viral, Cattle, Immunologic Techniques, Leukemia epidemiology, Leukemia immunology, Leukemia Virus, Bovine immunology, Netherlands, Cattle Diseases prevention & control, Leukemia veterinary
- Abstract
The results of studies on the incidence of enzootic bovine leukaemia in the Netherlands from 1968 to 1975 inclusive are given. The serological methods used (fluorescent antibody technique, immunoperoxidase test, micro complement fixation test and gel diffusion test) were found to be of great value especially for the early diagnosis of the disease. Antibodies to bovine leukaemia virus are already detected long before the onset of persistent lymphocytosis. The results obtained so far with serological methods confirm earlier haematological findings that enzootic bovine leukaemia is non-existent in the Dutch Friesian-Holstein and Meuse-Rhine-IJssel breeds. The first cases of enzootic bovine leukaemia were observed in import cattle in 1970. The geographic distribution of farms exploiting import cattle in which the disease has been diagnosed is presented on chart 1. Methods used to control enzootic bovine leukaemia are briefly described.
- Published
- 1976
28. Control of Marek's disease in the Netherlands. I. Isolation of an avirulent Marek's disease virus (strain CVI 988) and its use in laboratory vaccination trials.
- Author
-
Rispens BH, van Vloten H, Mastenbroek N, Maas HJ, and Schat KA
- Subjects
- Animals, Cells, Cultured, Ducks, Embryo, Nonmammalian, Female, Fibroblasts, Fluorescent Antibody Technique, Herpesviridae immunology, Herpesviridae pathogenicity, Immunodiffusion, Male, Marek Disease immunology, Marek Disease pathology, Marek Disease prevention & control, Netherlands, Virulence, Avian Leukosis prevention & control, Chickens, Herpesviridae isolation & purification, Herpesviridae Infections veterinary, Poultry Diseases prevention & control, Vaccination veterinary, Viral Vaccines
- Published
- 1972
29. Control of Marek's disease in the Netherlands. II. Field trials on vaccination with an avirulent strain (CVI 988) of Marek's disease virus.
- Author
-
Rispens BH, van Vloten H, Mastenbroek N, Maas JL, and Schat KA
- Subjects
- Animals, Cells, Cultured, Ducks, Embryo, Nonmammalian, Female, Fibroblasts, Herpesviridae pathogenicity, Injections, Intramuscular, Male, Marek Disease mortality, Marek Disease prevention & control, Netherlands, Virulence, Virus Cultivation, Avian Leukosis prevention & control, Chickens immunology, Herpesviridae immunology, Herpesviridae Infections veterinary, Poultry Diseases prevention & control, Vaccination veterinary, Viral Vaccines administration & dosage
- Published
- 1972
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