References of "Vanderplasschen, Alain"
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See detailViral subversion of the immune system
Gillet, L.; Vanderplasschen, Alain ULg

in Applications of gene-based technologies for improving animal production and health in developing countries (2005)

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See detailGenetic immunisation of cattle against bovine herpesvirus 1: glycoprotein gD confers higher protection than glycoprotein gC or tegument protein VP8.
Toussaint, Jean-Francois; Coen, Laurent; Letellier, Carine et al

in Veterinary Research (2005), 36(4), 529-44

Bovine herpesvirus 1 (BoHV-1) has frequently been used as a model for testing parameters affecting DNA immunisation in large animals like cattle. However, the selection of target antigens has been poorly ... [more ▼]

Bovine herpesvirus 1 (BoHV-1) has frequently been used as a model for testing parameters affecting DNA immunisation in large animals like cattle. However, the selection of target antigens has been poorly studied, and most of the experiments have been conducted in mice. In the present study, we demonstrated in cattle that a DNA vaccine encoding BoHV-1 glycoprotein gD induces higher neutralising antibody titres than vaccines encoding BoHV-1 gC. Additionally, we show that a DNA vaccine encoding a secreted form of gD induces a higher immune response than a vaccine encoding full-length gD. However, the enhanced immunogenicity associated with the secretion of gD could not be extended to the glycoprotein gC. The current study also describes for the first time the development and the evaluation of a DNA vaccine encoding the major tegument protein VP8. This construct, which is the first BoHV-1 plasmid vaccine candidate that is not directed against a surface glycoprotein, induced a high BoHV-1 specific cellular immunity but no humoral immune response. The calves vaccinated with the constructs encoding full-length and truncated gD showed a non-significant tenfold reduction of virus excretion after challenge. Those calves also excreted virus for significantly (p < 0.05) shorter periods (1.5 days) than the non-vaccinated controls. The other constructs encoding gC and VP8 antigens induced no virological protection as compared to controls. Altogether the DNA vaccines induced weaker immunity and protection than conventional marker vaccines tested previously, confirming the difficulty to develop efficient DNA vaccines in large species. [less ▲]

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See detailEvolution de l’herpèsvirus bovin 4 au cours des 1,5 derniers millions d’années
Dewals, Benjamin G ULg; Markine-Goriaynoff, Nicolas; Gaillard, Claude et al

Conference (2004, April)

L’herpèsvirus bovin 4 (BoHV-4) est un gammaherpèsvirus appartenant au genre Rhadinovirus. Récemment, une étude phylogénique a démontré que le gène Bo17 du BoHV-4 codant pour un homologue fonctionnel de la ... [more ▼]

L’herpèsvirus bovin 4 (BoHV-4) est un gammaherpèsvirus appartenant au genre Rhadinovirus. Récemment, une étude phylogénique a démontré que le gène Bo17 du BoHV-4 codant pour un homologue fonctionnel de la C2GnT-M cellulaire a été acquis d’un ancêtre direct ou indirect du buffle africain (Syncerus caffer) il y a quelques 1,5 millions d’années (Markine-Goriaynoff, N. et al. 2003. The core 2 beta-1,6-N-acetylglucosaminyltransferase-mucin encoded by bovine herpesvirus 4 was acquired from an ancestor of the African buffalo. J Virol 77:1784-92). Dans la présente étude, deux objectifs ont été poursuivis. Premièrement, dans le but de préciser l’origine du gène Bo17 du BoHV-4, le gène de la C2GnT-M de diverses sous-espèces de buffles a été séquencé. Les sous-espèces sélectionnées appartiennent aux espèces Syncerus caffer (pour les sous-espèces caffer, aequinoctialis et nanus) et Bubalus bubalis (pour les sous-espèces River, Swamp et Murrah). L’analyse phylogénique des séquences obtenues démontre que le BoHV-4 a acquis son gène Bo17 à partir d’un ancêtre direct de la sous-espèce Syncerus caffer caffer, soit bien après la séparation des Syncerus et des Bubalus. Le second but de cette étude était de déterminer si les souches de BoHV-4 isolées en Afrique à partir de buffle africain forment un groupe phylogénétiquement distinct au sein de l’espèce BoHV-4. Dans ce but, neuf souches représentatives de l’espèce BoHV-4 (dont trois isolées de buffle africain) ont été sequencées au niveau de 5 régions réparties sur l'entièreté du génome viral. L’analyse phylogénique de ces sequences démontre l’existence d’événements de recombinaisons inter-souches survenus récemment au cours de l’évolution. En conclusion, cette étude phylogénique a permis d’étabir que (i) le gène Bo17 du BoHV-4 a été acquis d’un ancêtre direct de la sous-espèce Syncerus caffer caffer de buffle africain, et (ii) que le génome du BoHV-4 a subi par la suite des phénomènes de recombinaisons inter-souches. [less ▲]

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See detailSuperinfection prevents recombination of the alphaherpesvirus bovine herpesvirus 1
Meurens, F.; Schynts, F.; Keil, G. M. et al

in Journal of Virology (2004), 78(8), 3872-3879

Homologous recombination between strains of the same alphaherpesvirus species occurs frequently both in vitro and in vivo. This process has been described between strains of herpes simplex virus type 1 ... [more ▼]

Homologous recombination between strains of the same alphaherpesvirus species occurs frequently both in vitro and in vivo. This process has been described between strains of herpes simplex virus type 1, herpes simplex virus type 2, pseudorabies virus, feline herpesvirus 1, varicella-zoster virus, and bovine herpesvirus 1 (BoHV-1). In vivo, the rise of recombinant viruses can be modulated by different factors, such as the dose of the inoculated viruses, the distance between inoculation sites, the time interval between inoculation of the first and the second virus, and the genes in which the mutations are located. The effect of the time interval between infections with two distinguishable BoHV-1 on recombination was studied in three ways: (i) recombination at the level of progeny viruses, (ii) interference induced by the first virus infection on beta-gallactosidase gene expression of a superinfecting virus, and (iii) recombination at the level of concatemeric DNA. A time interval of 2 to 8 h between two successive infections allows the establishment of a barrier, which reduces or prevents any successful superinfection needed to generate recombinant viruses. The dramatic effect of the time interval on the rise of recombinant viruses is particularly important for the risk assessment of recombination between glycoprotein E-negative marker vaccine and field strains that could threaten BoHV-1 control and eradication programs. [less ▲]

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See detailImproved antigenic methods for differential diagnosis of bovine, caprine, and cervine alphaherpesviruses related to bovine herpesvirus 1
Keuser, V.; Schynts, F.; Detry, Bruno et al

in Journal of Clinical Microbiology (2004), 42(3), 1228-1235

The control of infectious bovine rhinotracheitis induced by bovine herpesvirus 1 (BoHV-1) requires sensitive and specific diagnostic assays. As BoHV-1 is antigenically and genetically related to four ... [more ▼]

The control of infectious bovine rhinotracheitis induced by bovine herpesvirus 1 (BoHV-1) requires sensitive and specific diagnostic assays. As BoHV-1 is antigenically and genetically related to four other alphaherpesviruses of ruminants-namely, BoHV-5, caprine herpesvirus 1 (CpHV-1), cervine herpesvirus 1 (CvHV-1) and CvHV-2-diagnostic tests able to discriminate BoHV-1 from these related viruses are needed to avoid misdiagnosis, especially because some of these viruses are able to cross the species barrier. In this study, murine monoclonal antibodies (MAbs) specific for BoHV-1, BoHV-5, CpHV-1, CvHV-1, and CvHV-2 were produced with the aim of setting up an immunofluorescence assay able to discriminate between these related herpesviruses. Produced MAbs were selected for their viral specificity by enzyme-linked immunosorbent assay and indirect immunofluorescence staining of virus-infected cells. Radioimmunoprecipitation characterization of the selected MAbs revealed that four of them are directed against glycoprotein C (gC) and one of them is directed against gD of these related viruses. The obtained results demonstrate that the antibodies produced allow an unambiguous discrimination of each of the four alphaherpesviruses related to BoHV-1. [less ▲]

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See detailCeramides play a critical role in spontaneous neutrophil apoptosis
Seumois, G.; Fillet, Marianne ULg; Gillet, Laurent ULg et al

in Pflügers Archiv : European Journal of Physiology (2004), 447

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See detailSTAT5 promotes granulocyte survival during inflammation
Fievez, Laurence ULg; Desmet, Christophe ULg; Pajak, B. et al

in Pflügers Archiv : European Journal of Physiology (2004), 447

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See detailEffects of thiazolidinediones on tumor necrosis factor R alpha induced inflammatory cytokine expression
Desmet, Christophe ULg; Warsée, Barbara; Mélotte, D. et al

in Pflügers Archiv : European Journal of Physiology (2004), 447

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See detailGlycosyltransferases encoded by viruses.
Markine-Goriaynoff, Nicolas; Gillet, Laurent ULg; Van Etten, James L et al

in Journal of General Virology (The) (2004), 85(Pt 10), 2741-54

Studies of cellular biology in recent decades have highlighted the crucial roles of glycans in numerous important biological processes, raising the concept of glycomics that is now considered as important ... [more ▼]

Studies of cellular biology in recent decades have highlighted the crucial roles of glycans in numerous important biological processes, raising the concept of glycomics that is now considered as important as genomics, transcriptomics and proteomics. For millions of years, viruses have been co-evolving with their hosts. Consequently, during this co-evolution process, viruses have acquired mechanisms to mimic, hijack or sabotage host processes that favour their replication, including mechanisms to modify the glycome. The importance of the glycome in the regulation of host-virus interactions has recently led to a new concept called 'glycovirology'. One fascinating aspect of glycovirology is the study of how viruses affect the glycome. Viruses reach that goal either by regulating expression of host glycosyltransferases or by expressing their own glycosyltransferases. This review describes all virally encoded glycosyltransferases and discusses their established or putative functions. The description of these enzymes illustrates several intriguing aspects of virology and provides further support for the importance of glycomics in biological processes. [less ▲]

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See detailThe core 2 beta-1,6-N-acetylglucosaminyltransferase-M encoded by bovine herpesvirus 4 is not essential for virus replication despite contributing to post-translational modifications of structural proteins.
Markine-Goriaynoff, Nicolas; Gillet, Laurent ULg; Karlsen, Odd A et al

in Journal of General Virology (The) (2004), 85(Pt 2), 355-67

The Bo17 gene of bovine herpesvirus 4 (BoHV-4) is the only virus gene known to date that encodes a homologue of the cellular core 2 beta-1,6-N-acetylglucosaminyltransferase-mucine type (C2GnT-M). Recently ... [more ▼]

The Bo17 gene of bovine herpesvirus 4 (BoHV-4) is the only virus gene known to date that encodes a homologue of the cellular core 2 beta-1,6-N-acetylglucosaminyltransferase-mucine type (C2GnT-M). Recently, our phylogenetic study revealed that the Bo17 gene has been acquired from an ancestor of the African buffalo around 1.5 million years ago. Despite this recent origin, the Bo17 sequence has spread to fixation in the virus population possibly by natural selection. Supporting the latter hypothesis, it has been shown by our group for the V. test strain that Bo17 is expressed during BoHV-4 replication in vitro, and that Bo17 expression product (pBo17) has all three enzymic activities exhibited by cellular C2GnT-M, i.e. core 2, core 4 and I branching activities. In the present study, firstly it was investigated whether encoding a functional C2GnT-M is a general property of BoHV-4 strains. Analysis of nine representative strains of the BoHV-4 species revealed that all of them express the Bo17 gene and the associated core 2 branching activity during virus replication in vitro. Secondly, in order to investigate the roles of Bo17, its kinetic class of expression was analysed and a deleted recombinant strain was produced. These experiments revealed that Bo17 is expressed as an early gene which is not essential for virus replication in vitro. However, comparison of the structural proteins, produced by the wild-type, the revertant and the deleted viruses, by 2D gels demonstrated that pBo17 contributes to the post-translational modifications of structural proteins. Possible roles of Bo17 in vivo are discussed. [less ▲]

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See detailBovine herpesvirus 1 glycoprotein D expression in bovine upper respiratory tract mediated by a human adenovirus type 5
Gogev, S.; Georgin, J. P.; Schynts, F. et al

in Veterinary Research (2004), 35(6, Nov-Dec), 715-721

Bovine herpesvirus 1 glycoprotein D (gD) gene expression by recombinant replication defective human adenovirus type 5 (HAdV-5) was investigated in calves using indirect immunofluorescence microscopy (IIFM ... [more ▼]

Bovine herpesvirus 1 glycoprotein D (gD) gene expression by recombinant replication defective human adenovirus type 5 (HAdV-5) was investigated in calves using indirect immunofluorescence microscopy (IIFM), confocal laser scanning microscopy (CLSM) and RT-PCR. One fold intranasal instillation of HAdV-5-expressing gD in the cattle upper respiratory tract showed a short term expression of at least 5 days, but not 10 days, limited only to epithelial cells localised in the epithelium of the nasal mucosa in one out of six calves. Observed limited gene transfer into well differentiated cattle airway epithelial cells must be taken into consideration in order to enhance transfection efficiency, and consequently the vaccine potential of this vector. [less ▲]

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See detailDelayed neutrophil apoptosis in bovine subclinical mastitis.
Boutet, Philippe ULg; Boulanger, D.; Gillet, Laurent ULg et al

in Journal of Dairy Science (2004), 87(12), 4104-4114

Bovine subclinical mastitis can be defined as a moderated inflammatory disease characterized by a persistent accumulation of neutrophils in milk. As GMCSF-mediated delay of neutrophil apoptosis ... [more ▼]

Bovine subclinical mastitis can be defined as a moderated inflammatory disease characterized by a persistent accumulation of neutrophils in milk. As GMCSF-mediated delay of neutrophil apoptosis contributes to the accumulation of inflammatory cells at the site of inflammation in many human diseases, we sought to determine whether subclinical mastitis in cows is also associated with a GMCSF-dependent increase in milk-neutrophil survival. We first addressed the hypothesis that GMCSF delays bovine neutrophil apoptosis by activation of the signal transducer and activator of transcription (STAT) family members STAT3 and STAT5, which are critical regulators of the expression of various Bcl-2 family proteins. Granulocyte-macrophage colony-stimulating factor significantly delayed apoptosis of blood neutrophils obtained from healthy cows. In these cells, GMCSF activated STAT5, but not STAT3, and induced an increase in the mRNA of the antiapoptotic Bcl-2 member, Bcl-xL. Granulocyte-macrophage colony-stimulating factor-dependent STAT5 activation and up-regulation of Bcl-xL mRNA were blocked by the Jak inhibitor, AG-490. This inhibition was associated with abrogation of the prosurvival effect of GMCSF, demonstrating a key role for STAT5 in delayed neutrophil apoptosis. We further found that GMCSF expression was increased in milk cells from cows affected with subclinical mastitis. Neutrophils from these cows demonstrated a significant delay of apoptosis as compared with neutrophils obtained from healthy cows and were unresponsive to GMCSF. Active STAT5 complexes were detected in these neutrophils. Finally, in the presence of AG-490, apoptosis was induced and a time-dependent down-regulation of Bcl-xL mRNA was observed in milk neutrophils from mastitis-affected cows. These results indicate that neutrophil survival is enhanced in milk of subclinical mastitis-affected cows and suggest a role for a GMCSF-activated STAT5 signaling pathway in this phenomenon. This pathway could thus represent a target for the control of persistent accumulation of neutrophils in the bovine mammary gland [less ▲]

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See detailInvestigation of the susceptibility of human cell lines to bovine herpesvirus 4 infection: Demonstration that human cells can support a nonpermissive persistent infection which protects them against tumor necrosis factor alpha-induced apoptosis
Gillet, Laurent ULg; Minner, F.; Detry, Bruno et al

in Journal of Virology (2004), 78(5), 2336-2347

Bovine herpesvirus 4 (BoHV-4) is a gammaherpesvirus that has a worldwide distribution in the population of cattle. Many factors make human contamination by BoHV-4 likely to occur. In this study, we ... [more ▼]

Bovine herpesvirus 4 (BoHV-4) is a gammaherpesvirus that has a worldwide distribution in the population of cattle. Many factors make human contamination by BoHV-4 likely to occur. In this study, we performed in vitro experiments to assess the risk and the consequences of human infection by BoHV-4. First, by using a recombinant BoHV-4 strain expressing enhanced green fluorescent protein under the control of the human cytomegalovirus immediate-early gene promoter, we tested 21 human cell lines for their sensitivity and their permissiveness to BoHV-4 infection. These experiments revealed that human cell lines from lymphoid and myeloid origins were resistant to infection, whereas epithelial cells, carcinoma cells, or adenocarcinoma cells isolated from various organs were sensitive but poorly permissive to BoHV-4 infection. Second, by using the HeLa cell line as a model of human cells sensitive but not permissive to BoHV-4 infection, we investigated the resistance of infected cells to apoptosis and the persistence of the infection through cellular divisions. The results obtained can be summarized as follows. (i) BoHV-4 nonpermissive infection of HeLa cells protects them against tumor necrosis factor alpha-induced apoptosis. (ii) BoHV-4 infection of HeLa cells persists in cell culture; however, the percentage of infected cells decreases with time due to erratic transmission of the viral genome through cell division. (iii) BoHV-4 infection has no effect on the rate of HeLa cell division. Altogether, these data suggest that BoHV-4 could infect humans. This study also stresses the importance of considering the insidious effects of nonpermissive infection when the biosafety of animal gammaherpesviruses for humans is being considered. [less ▲]

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See detailDownregulation of ICAM-1 and VCAM-1 expression in endothelial cells treated by photodynamic therapy
Volanti, Cédric ULg; Gloire, Geoffrey ULg; Vanderplasschen, Alain ULg et al

in Oncogene (2004), 23(53), 8649-8658

Photodynamic therapy (PDT) is a treatment for cancer and several noncancerous proliferating cell diseases that depends on the uptake of a photosensitizing compound followed by selective irradiation with ... [more ▼]

Photodynamic therapy (PDT) is a treatment for cancer and several noncancerous proliferating cell diseases that depends on the uptake of a photosensitizing compound followed by selective irradiation with visible light. In the presence of oxygen, irradiation leads to the production of reactive oxygen species (ROS). A large production of ROS induces the death of cancer cells by apoptosis or necrosis. A small ROS production can activate various cellular pathways. Here, we show that PDT by pyropheophorbide-a methyl ester (PPME) induces the activation of nuclear factor kappa B (NF-kappaB) in HMEC-1 cells. NF-kappaB is active since it binds to the NF-kappaB sites of both ICAM-1 and vascular cell adhesion molecule-1 (VCAM-1) promoters and induces the transcription of several NF-kappaB target genes such as those of IL-6, ICAM-1, VCAM-1. In contrast, expression of ICAM-1 and VCAM-1 at the protein level was not observed, although we measured an IL-6 secretion. Using specific chemical inhibitors, we showed that the lack of ICAM-1 and VCAM-1 expression is the consequence of their degradation by lysosomal proteases. The proteasome and calpain pathways were not involved. All these observations were consistent with the fact that no adhesion of granulocytes was observed in these conditions. [less ▲]

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See detailSTAT5 promotes granulocyte survival during lung inflammation
Fievez, Laurence ULg; Desmet, Christophe ULg; Seumois, G. et al

in Proceedings: 22nd Symposium of the Veterinary and Comparative Respiratory Society (2004)

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See detailRise and survival of bovine herpesvirus 1 recombinants after primary infection and reactivation from latency
Schynts, F.; Meurens, F.; Detry, Bruno et al

in Journal of Virology (2003), 77(23), 12535-12542

Recombination is thought to be an important source of genetic variation in herpesviruses. Several studies, performed in vitro or in vivo, detected recombinant viruses after the coinoculation of two ... [more ▼]

Recombination is thought to be an important source of genetic variation in herpesviruses. Several studies, performed in vitro or in vivo, detected recombinant viruses after the coinoculation of two distinguishable strains of the same herpesvirus species. However, none of these studies investigated the evolution of the relative proportions of parental versus recombinant progeny populations after coinoculation of the natural host, both during the excretion and the reexcretion period. In the present study, we address this by studying the infection of cattle with bovine herpesvirus 1 (BoHV-1). The recombination of two BoHV-1 mutants lacking either glycoprotein C (gC(-)/gE(+)) or E (gC(+)/gE(-)) was investigated after inoculation of cattle by the natural route of infection. The results demonstrated that (i) recombination is a frequent event in vivo since recombinants (gC(+)/gE(+) and gC(-)/gE(-)) were detected in all coinoculated calves, (ii) relative proportions of progeny populations evolved during the excretion period toward a situation where two populations (gC(+)/gE(+) and gC(-)/gE(+)) predominated without fully outcompeting the presence of the two other detected populations (gC(+)/gE(-) and gC(-)/gE(-)), and (iii) after reactivation from latency, no gC(+)/gE(-) and gC(-)/gE(-) progeny viruses were detected, although gC(+)/gE(-) mutants, when inoculated alone, were detected after reactivation treatment. In view of these data, the importance of gE in the biology of BoHV-1 infection and the role of recombination in herpesvirus evolution are discussed. [less ▲]

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See detailL'herpèsvirus alcélaphin 1, l'agent responsable de la forme africaine du coryza gangreneux
Dewals, Benjamin G ULg; Boudry, Christel ULg; Markine-Goriaynoff, Nicolas ULg et al

in Annales de Médecine Vétérinaire (2003), 147(1, FEB-MAR), 1-15

Malignant catarrhal fever (MCF) is a pathology usually lethal which has been described in a large number of ruminant species. Based on the etiology, two main forms of MCF have been described, i.e., the ... [more ▼]

Malignant catarrhal fever (MCF) is a pathology usually lethal which has been described in a large number of ruminant species. Based on the etiology, two main forms of MCF have been described, i.e., the European and the African forms due to ovine herpesvirus 2 (OvHV-2) and alcelaphine herpesvirus 1 (AlHV-1), respectively. The present review is devoted to the African form of MCF and to its causative agent AlHV-1. AlHV-1 belongs to the Gammaherpesvirinae subfamily of the Herpesviridae family. Wildebeests (Connochaetes spp) carry AlHV-1, which is lethal for a large number of ruminant species, while apparently harmless to its natural host. In hosts susceptible to MCF, the pathology is characterized by fever, extensive lymphadenopathy, ulcerative lesions of the digestive and the upper respiratory tracts mucous membranes and severe keratoconjunctivitis. In the present paper, we will review the data available to date on AlHV-1 and on the African form of MCF with emphasis on the pathogenesis, clinical signs and anatomo-pathological lesions of MCF. Finally, we will discuss the relationship between AlHV-1 and wildebeest as an example of symbiosis between a virus and its natural host. [less ▲]

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See detailCeramides play a critical role in spontaneous neutrophil apoptosis
Seumois, G.; Fillet, Marianne ULg; Gillet, Laurent ULg et al

Poster (2003)

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See detailInduce triploidy by heat shock in Eurasian perch, Perca fluviatilis
Rougeot, Carole ULg; Minet, Laurent; Prignon, Christian ULg et al

in Aquatic Living Resources (2003), 16(2, MAR-APR), 90-94

In Eurasian perch (Perca fluviatilis), females grow significantly faster than males. Moreover, gonadal development has a significant negative impact on somatic growth and fillet yield. In order to induce ... [more ▼]

In Eurasian perch (Perca fluviatilis), females grow significantly faster than males. Moreover, gonadal development has a significant negative impact on somatic growth and fillet yield. In order to induce sterility, triploidy induction was attempted by subjecting fertilised eggs to heat shocks. Different combinations of temperature (28, 30, 34, 35 and 36 degreesC), duration (2, 5, 10 and 25 min) and time of shock initiation (TI = 3, 5 and 7 min post-fertilisation) were tested. Flow cytometry analysis was used to assess ploidy level of control and heat-shocked larvae. Low intensity (28-30 degreesC) and long duration (10 and 25 min) shocks lead to significantly higher survival (44 +/- 26%) and triploidisation (71 +/- 26%) rates than high intensity (34-36 degreesC) and short duration (2 and 5 min) shocks (17 +/- 19% and 21 +/- 26%, respectively). The most effective conditions for efficient triploidy induction were low intensity shock of 30 degreesC, applied 5 min post-fertilisation for 25 min. This treatment led to the production of all-triploid populations (100%) with up to 43% survival rate. (C) 2003 Editions scientifiques et medicales Elsevier SAS and Ifremer/IRD/Inra/Cemagref. All rights reserved. [less ▲]

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