Mohammed EL Houadfi - Academia.edu (original) (raw)

Papers by Mohammed EL Houadfi

Research paper thumbnail of Low Pathogenic Avian Influenza H9N2 Viruses in Morocco: Antigenic and Molecular Evolution from 2021 to 2023

Viruses, Nov 29, 2023

This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

Research paper thumbnail of Application du système de scoring lésionnel pour contribuer à l’étude de la pathogénicité du virus de l’influenza aviaire faiblement pathogène H9N2 chez le poulet de chair infecté expérimentalement

DOAJ (DOAJ: Directory of Open Access Journals), Sep 1, 2021

Suite à l'introduction du virus de l'influenza aviaire faiblement pathogène H9N2 au Maroc en 2016... more Suite à l'introduction du virus de l'influenza aviaire faiblement pathogène H9N2 au Maroc en 2016, une étude de la pathogénicité du virus a été effectuée, pour bien comprendre la pathophysiologie de la maladie et son rôle dans les dégâts observés au niveau du terrain. L'étude a été effectuée dans des conditions contrôlées pour pouvoir ressortir le véritable impact du virus H9N2 seul en limitant les infections concomitantes. Pour ce faire, 110 poulets de chair d'un jour vaccinés à un jour d'âge, contre le virus de l'influenza aviaire faiblement pathogène H9N2, ont été élevés et entretenus dans des isolateurs. A 21 jours, les poussins ont été répartis en trois lots, deux lots (vC, nvC) ont été inoculé par la souche marocaine du virus H9N2 (GenBank accession number : LT 598532) et un lot témoin non challengé (vNC). Les résultats des examens cliniques ont révélé une gêne respiratoire seulement et aucune mortalité. Deux autopsies ont été programmées à 5 et à 12 jours post-challenge. Sur le plan lésionnel, une trachéite, un épaississement des sacs aériens, et une congestion pulmonaire ont été observés pendant la première autopsie, lors de la deuxième, seulement l'épaississement des sacs aériens a persisté. L'étude histopathologique réalisée sur les organes prélevés lors des autopsies, a révélé une trachéite lympho-histiocytaire, une bronchite sévère, une néphrite lymphocytaire légère et une déplétion lymphocytaire au niveau de la rate à 5 jours post challenge, à 12 jours post-challenge, les lésions ont régressé et seulement quelques cas de trachéite ont été détectés. La présente étude est la première à avoir étudié l'effet pathogène du virus seul dans des conditions contrôlées, les résultats indiquent que l'infection par le virus seul ne reproduit pas la maladie telle qu'elle est rapportée dans le terrain et que d'autres facteurs (infections concomitantes, conditions d'élevage et stress environnemental…) peuvent être à l'origine de la gravité des dégâts rapportés, l'équipe a aussi conclu que la souche marocaine du virus de l'IA H9N2 a un tropisme essentiellement respiratoire et un effet néphropathogène faible.

Research paper thumbnail of Molecular characterization and phylogenetic analysis of very virulent infectious bursal disease virus circulating in Morocco during 2016-2017

Archives of Virology, Oct 26, 2018

Very virulent infectious bursal disease virus (vvIBDV), the cause of significant economic losses ... more Very virulent infectious bursal disease virus (vvIBDV), the cause of significant economic losses in many poultry-producing areas, has been present in Morocco since 1991. In spite of the introduction of vaccination, disease outbreaks are frequently observed. To ascertain if vaccines failure may be due to the emergence of new strains, the aim of this study was to perform for the first time the molecular characterization of vvIBDV strains circulating in Morocco by focusing on the hypervariable region (HVR) of the VP2 protein, which is frequently used for molecular epidemiology and phylogenetic studies. Field samples of haemorrhagic bursae of Fabricius were collected for molecular characterization in different parts of the country during 2016-2017 from 48 chicken flocks showing symptoms of disease. In a phylogenetic tree, nucleotide sequences containing the VP2 HVR of 13 samples that were positive for vvIBDV formed a common branch with those of vvIBDV references strains published in GenBank, but they clearly grouped into a distinct subcluster. An alignment of the deduced amino acid sequences, in addition to confirming the presence of the “signature” typical of the vvIBDV HVR, also revealed the presence of substitutions in hydrophilic loops that are known to be involved in the elicitation of neutralizing antibodies. One of these substitutions is unique to the Moroccan isolates. These results represent the first molecular characterization of vvIBDV isolates in Morocco and may indicate that one of the causes of vaccine ineffectiveness is antigenic drift.

Research paper thumbnail of Phylogenetic analysis of avian infectious bronchitis virus isolated in Morocco: a retrospective study, 1983 to 2014

HAL (Le Centre pour la Communication Scientifique Directe), Jun 21, 2016

Background: Infectious bronchitis virus (IBV), a major pathogen of commercial poultry flocks, cir... more Background: Infectious bronchitis virus (IBV), a major pathogen of commercial poultry flocks, circulates in the form of several serotypes/genotypes. Only a few amino-acid changes in the S1 subunit of wild-type IBVS proteins may result in mutants unaffected by current vaccines. Methods: Partial S1 gene sequences of 3 IBV isolates of the Moroccan Italy 02 genotype from vaccinated and unvaccinated broiler chicken flocks, located in southern and central regions of Morocco, were amplified by RT-PCR, sequenced, and aligned for phylogenetic and amino-acid similarity analyses. Results: The three isolates were found genetically highly distant from known avian IBV based on partial sequences of their S1 genes: gammaCoV/chicken/Morocco/I01/2011(IBV/Morocco/01), gammaCoV/chicken/Morocco/I30/2010 (IBV/Morocco/30), and gammaCoV/chicken/Morocco/I38/2013 (IBV/Morocco/38), nucleotide sequence identities reached 89.5 % to 90.9 % among the three isolates. The deduced protein sequence identities ranged from 29.7 % (between IBV/Morocco/38 and Egypt SCU-14/2013-1) to 78.2 % (between IBV/Morocco/01 and Spain/05/866). Amino acid sequence comparison and phylogenetic analysis indicated the emergence of a new Moroccan genotype, clustering with regionally related isolates from Spain (Spain/05/866) and belonging to a new sub-genotype. Conclusion: Our sequencing results demonstrate a co-circulation of wild-type infectious bronchitis viruses in broiler chickens. These results justify permanent monitoring of circulating strains in order to rationally modify vaccination strategies to make them appropriate to the evolving field situation.

Research paper thumbnail of Severe outbreaks of infectious Bursal Disease in Morocco

Research paper thumbnail of Phylogenetic analysis of avian infectious bronchitis virus isolates from Morocco: a retrospective study (1983 to 2014)

Virologica Sinica, Apr 1, 2017

Research paper thumbnail of Isolation of avian infectious bronchitis viruses in Morocco including an enterotropic variant

Research paper thumbnail of An Enterotropic Avian Infectious Bronchitis Virus

Of six isolates of infectious bronchitis (IB) virus isolated from commercial poultry flocks in Mo... more Of six isolates of infectious bronchitis (IB) virus isolated from commercial poultry flocks in Morocco, five (designated D,E,F, H and M) were related serologically to the Massachusetts serotype, while a sixth, (designated G) was found to be different from any previously reported serotype of IB virus. Neutralising antibodies to this virus have been detected in the sera of commercial chicken flocks from a number of regions in Britain. While isolate G, in common with the other 5 isolates, caused respiratory disease typical of IB in 3-week old SPF chicks, it showed a particular predilection for the alimentary tract, and at various times up to 28 days could be isolated from all regions between oesophagus and bursa of Fabricus. Greatest persistence occurred in the anterior regions (oesophagus, proventriculus and duodenum).

Research paper thumbnail of Assessing the Efficacy of Recombinant Newcastle Disease Virus Vaccines (Double-Insert vHVT-IBD-ND and Single-Insert vHVT-ND) Followed by a Vaccination with a Live Newcastle Disease Vaccine Against a Moroccan Velogenic Newcastle Disease Challenge in Commercial Broilers

Research paper thumbnail of Protection conferred by H120 vaccine against IBV Moroccan Italy 02 in commercial broilers and SPF chickens

HAL (Le Centre pour la Communication Scientifique Directe), Jun 21, 2016

Research paper thumbnail of Etude des performances zootechniques et sensibilité au virus de l’Influenza Aviaire H9N2 chez une race de poulet croisé à croissance intermediaire

Revue Marocaine des Sciences Agronomiques et Vétérinaires, Sep 15, 2021

Research paper thumbnail of Profil moléculaire et épidémiologique du virus de la bursite infectieuse aviaire circulant au Maroc entre 2013 et 2016

Revue Marocaine des Sciences Agronomiques et Vétérinaires, Sep 15, 2021

Research paper thumbnail of RETRACTED ARTICLE: Co-infection of turkeys with <i>Escherichia coli</i> (O78) and H6N1 avian influenza virus

We, the Editors and Publisher of the journal <i>Avian Pathology</i>, have retracted t... more We, the Editors and Publisher of the journal <i>Avian Pathology</i>, have retracted the following article: Sajid Umar, Maxence Delverdier, Mattias Delpont, Sakhia F.Z. Belkasmi, Angélique Teillaud, Céline Bleuart, Isabelle Pardo, Mohammed EL Houadfi, Jean-Luc Guérin & Mariette F. Ducatez 'Co-infection of turkeys with Escherichia coli (O78) and H6N1 avian influenza virus' (47:3, 2018) https://www.tandfonline.com/doi/full/10.1080/03079457.2018.1449942The above article has been retracted as, subsequent to publication, significant duplication has been found in content with the following unreferenced earlier published works: Qamar-un-Nisa, Muhammad Younus, Muti-ur-Rehman, Azhar Maqbool and Sajid Umar. 2017. Pathological Alterations during Co-Infection of Newcastle Disease Virus with Escherichia coli in Broiler Chicken. <i>Pakistan Journal of Zoology</i>, 50(2), pp 401–797, DOI: 10.17582/journal.pjz/2018.50.2.495.503Shahid Jaleel, Muhammad Younus, Asif Idre...

Research paper thumbnail of Evaluation semi-quantitative des lésions histopathologiques respiratoires chez la dinde moyennant un système de scoring lésionnel: Infection expérimentale par le virus de l’influenza aviaire faiblement pathogène H9N2

Revue Marocaine des Sciences Agronomiques et Vétérinaires, Sep 15, 2021

Research paper thumbnail of Avian Influenza a H9N2 Viruses in Morocco, 2018–2019

Viruses, 2022

Low pathogenic H9N2 avian influenza (LPAI H9N2) is considered one of the most important diseases ... more Low pathogenic H9N2 avian influenza (LPAI H9N2) is considered one of the most important diseases found in poultry (broiler, laying hens, breeding chickens, and turkeys). This infection causes considerable economic losses. The objective of this work was to monitor and assess the presence of avian influenza virus (AIV) H9N2 in eight different regions of Morocco using real-time RT-PCR, and to assess the phylogenetic and molecular evolution of the H9N2 viruses between 2016 and 2019. Field samples were collected from 108 farms suspected of being infected with LPAI H9N2 virus. Samples were analyzed using H9N2-specific real-time RT-PCR. Highly positive samples were subjected to virus isolation and seven isolates were fully sequenced. Low pathogenic H9N2 avian influenza virus was introduced in Morocco in 2016. We show that in 2018–2019, the virus was still present irrespective of vaccination status. Phylogenetic and molecular analyses showed mutations related to virulence, although our viru...

Research paper thumbnail of Les souches très virulentes du virus de la bursite infectieuse aviaire: Revue bibliographique et situation épidémiologique

Revue Marocaine des Sciences Agronomiques et Vétérinaires, 2020

Cette revue se focalise sur le virus très virulent de la bursite infectieuse aviaire (vvIBDV). Ce... more Cette revue se focalise sur le virus très virulent de la bursite infectieuse aviaire (vvIBDV). Ce virus est réparti dans le monde entier, causant des pertes économiques très considérable représentant une menace pour l'industrie de la volaille. L'émergence des formes aiguës de la maladie a radicalement changé l'épidémiologie de l'IBD. Bien que leur origine soit encore à l'étude, les vvIBDV se sont répandus dans le monde entier de manière explosive mais conservée. Cela pose la question de l'origine des vvIBDV, de la possibilité d'existence des réservoirs et de l'émergence possible de nouvelles lignées distinctes dans l'avenir. Il est devenu évident que les acides aminés dans la région hypervariable de la protéine virale VP2 constitue une base moléculaire de la variation antigénique, mais aucune mutation qui détermine la pathogénicité n'a été identifiée. Ces marqueurs moléculaires des souches vvIBDV doivent être considérés davantage comme une évo...

Research paper thumbnail of Esbl resistance APEC (eng) v2

Research paper thumbnail of Neurofibromatose segmentar: relato de caso

Anais Brasileiros De Dermatologia, 1999

Research paper thumbnail of Prevalence and molecular characterization of avian infectious bronchitis virus in poultry flocks in Morocco from 2010 to 2014 and first detection of Italy 02 in Africa

Avian pathology : journal of the W.V.P.A, 2015

The aim of this study was to investigate the prevalence and diversity of infectious bronchitis vi... more The aim of this study was to investigate the prevalence and diversity of infectious bronchitis virus (IBV) genotypes in poultry flocks in 16 areas of Morocco between 2010 and 2014. A total of 360 chicken flocks suspected of being infected by IBV were screened for the IBV N gene using real-time reverse transcriptase-polymerase chain reaction (RT-PCR). Flocks were classified into four groups according to their IBV vaccination programme. Group 1 contained unvaccinated birds. Group 2 received a single application of live H120 vaccine. Groups 3 and 4 birds received one or two booster vaccination(s), respectively, mostly using the H120 vaccine. The real-time RT-PCR results showed that 51.7% of the flocks were positive for the IBV genome with geographical disparities. Molecular characterization of IBV was performed on 50 RT-PCR positive samples by partially sequencing the S1 gene, including the hypervariable regions (nucleotides 705-1097). Two predominant genotypes were detected, with the ...

Research paper thumbnail of Moroccan

Phylogenetic analysis of avian infectious bronchitis virus S1 glycoprotein regions reveals emerge... more Phylogenetic analysis of avian infectious bronchitis virus S1 glycoprotein regions reveals emergence of a new genotype in

Research paper thumbnail of Low Pathogenic Avian Influenza H9N2 Viruses in Morocco: Antigenic and Molecular Evolution from 2021 to 2023

Viruses, Nov 29, 2023

This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

Research paper thumbnail of Application du système de scoring lésionnel pour contribuer à l’étude de la pathogénicité du virus de l’influenza aviaire faiblement pathogène H9N2 chez le poulet de chair infecté expérimentalement

DOAJ (DOAJ: Directory of Open Access Journals), Sep 1, 2021

Suite à l'introduction du virus de l'influenza aviaire faiblement pathogène H9N2 au Maroc en 2016... more Suite à l'introduction du virus de l'influenza aviaire faiblement pathogène H9N2 au Maroc en 2016, une étude de la pathogénicité du virus a été effectuée, pour bien comprendre la pathophysiologie de la maladie et son rôle dans les dégâts observés au niveau du terrain. L'étude a été effectuée dans des conditions contrôlées pour pouvoir ressortir le véritable impact du virus H9N2 seul en limitant les infections concomitantes. Pour ce faire, 110 poulets de chair d'un jour vaccinés à un jour d'âge, contre le virus de l'influenza aviaire faiblement pathogène H9N2, ont été élevés et entretenus dans des isolateurs. A 21 jours, les poussins ont été répartis en trois lots, deux lots (vC, nvC) ont été inoculé par la souche marocaine du virus H9N2 (GenBank accession number : LT 598532) et un lot témoin non challengé (vNC). Les résultats des examens cliniques ont révélé une gêne respiratoire seulement et aucune mortalité. Deux autopsies ont été programmées à 5 et à 12 jours post-challenge. Sur le plan lésionnel, une trachéite, un épaississement des sacs aériens, et une congestion pulmonaire ont été observés pendant la première autopsie, lors de la deuxième, seulement l'épaississement des sacs aériens a persisté. L'étude histopathologique réalisée sur les organes prélevés lors des autopsies, a révélé une trachéite lympho-histiocytaire, une bronchite sévère, une néphrite lymphocytaire légère et une déplétion lymphocytaire au niveau de la rate à 5 jours post challenge, à 12 jours post-challenge, les lésions ont régressé et seulement quelques cas de trachéite ont été détectés. La présente étude est la première à avoir étudié l'effet pathogène du virus seul dans des conditions contrôlées, les résultats indiquent que l'infection par le virus seul ne reproduit pas la maladie telle qu'elle est rapportée dans le terrain et que d'autres facteurs (infections concomitantes, conditions d'élevage et stress environnemental…) peuvent être à l'origine de la gravité des dégâts rapportés, l'équipe a aussi conclu que la souche marocaine du virus de l'IA H9N2 a un tropisme essentiellement respiratoire et un effet néphropathogène faible.

Research paper thumbnail of Molecular characterization and phylogenetic analysis of very virulent infectious bursal disease virus circulating in Morocco during 2016-2017

Archives of Virology, Oct 26, 2018

Very virulent infectious bursal disease virus (vvIBDV), the cause of significant economic losses ... more Very virulent infectious bursal disease virus (vvIBDV), the cause of significant economic losses in many poultry-producing areas, has been present in Morocco since 1991. In spite of the introduction of vaccination, disease outbreaks are frequently observed. To ascertain if vaccines failure may be due to the emergence of new strains, the aim of this study was to perform for the first time the molecular characterization of vvIBDV strains circulating in Morocco by focusing on the hypervariable region (HVR) of the VP2 protein, which is frequently used for molecular epidemiology and phylogenetic studies. Field samples of haemorrhagic bursae of Fabricius were collected for molecular characterization in different parts of the country during 2016-2017 from 48 chicken flocks showing symptoms of disease. In a phylogenetic tree, nucleotide sequences containing the VP2 HVR of 13 samples that were positive for vvIBDV formed a common branch with those of vvIBDV references strains published in GenBank, but they clearly grouped into a distinct subcluster. An alignment of the deduced amino acid sequences, in addition to confirming the presence of the “signature” typical of the vvIBDV HVR, also revealed the presence of substitutions in hydrophilic loops that are known to be involved in the elicitation of neutralizing antibodies. One of these substitutions is unique to the Moroccan isolates. These results represent the first molecular characterization of vvIBDV isolates in Morocco and may indicate that one of the causes of vaccine ineffectiveness is antigenic drift.

Research paper thumbnail of Phylogenetic analysis of avian infectious bronchitis virus isolated in Morocco: a retrospective study, 1983 to 2014

HAL (Le Centre pour la Communication Scientifique Directe), Jun 21, 2016

Background: Infectious bronchitis virus (IBV), a major pathogen of commercial poultry flocks, cir... more Background: Infectious bronchitis virus (IBV), a major pathogen of commercial poultry flocks, circulates in the form of several serotypes/genotypes. Only a few amino-acid changes in the S1 subunit of wild-type IBVS proteins may result in mutants unaffected by current vaccines. Methods: Partial S1 gene sequences of 3 IBV isolates of the Moroccan Italy 02 genotype from vaccinated and unvaccinated broiler chicken flocks, located in southern and central regions of Morocco, were amplified by RT-PCR, sequenced, and aligned for phylogenetic and amino-acid similarity analyses. Results: The three isolates were found genetically highly distant from known avian IBV based on partial sequences of their S1 genes: gammaCoV/chicken/Morocco/I01/2011(IBV/Morocco/01), gammaCoV/chicken/Morocco/I30/2010 (IBV/Morocco/30), and gammaCoV/chicken/Morocco/I38/2013 (IBV/Morocco/38), nucleotide sequence identities reached 89.5 % to 90.9 % among the three isolates. The deduced protein sequence identities ranged from 29.7 % (between IBV/Morocco/38 and Egypt SCU-14/2013-1) to 78.2 % (between IBV/Morocco/01 and Spain/05/866). Amino acid sequence comparison and phylogenetic analysis indicated the emergence of a new Moroccan genotype, clustering with regionally related isolates from Spain (Spain/05/866) and belonging to a new sub-genotype. Conclusion: Our sequencing results demonstrate a co-circulation of wild-type infectious bronchitis viruses in broiler chickens. These results justify permanent monitoring of circulating strains in order to rationally modify vaccination strategies to make them appropriate to the evolving field situation.

Research paper thumbnail of Severe outbreaks of infectious Bursal Disease in Morocco

Research paper thumbnail of Phylogenetic analysis of avian infectious bronchitis virus isolates from Morocco: a retrospective study (1983 to 2014)

Virologica Sinica, Apr 1, 2017

Research paper thumbnail of Isolation of avian infectious bronchitis viruses in Morocco including an enterotropic variant

Research paper thumbnail of An Enterotropic Avian Infectious Bronchitis Virus

Of six isolates of infectious bronchitis (IB) virus isolated from commercial poultry flocks in Mo... more Of six isolates of infectious bronchitis (IB) virus isolated from commercial poultry flocks in Morocco, five (designated D,E,F, H and M) were related serologically to the Massachusetts serotype, while a sixth, (designated G) was found to be different from any previously reported serotype of IB virus. Neutralising antibodies to this virus have been detected in the sera of commercial chicken flocks from a number of regions in Britain. While isolate G, in common with the other 5 isolates, caused respiratory disease typical of IB in 3-week old SPF chicks, it showed a particular predilection for the alimentary tract, and at various times up to 28 days could be isolated from all regions between oesophagus and bursa of Fabricus. Greatest persistence occurred in the anterior regions (oesophagus, proventriculus and duodenum).

Research paper thumbnail of Assessing the Efficacy of Recombinant Newcastle Disease Virus Vaccines (Double-Insert vHVT-IBD-ND and Single-Insert vHVT-ND) Followed by a Vaccination with a Live Newcastle Disease Vaccine Against a Moroccan Velogenic Newcastle Disease Challenge in Commercial Broilers

Research paper thumbnail of Protection conferred by H120 vaccine against IBV Moroccan Italy 02 in commercial broilers and SPF chickens

HAL (Le Centre pour la Communication Scientifique Directe), Jun 21, 2016

Research paper thumbnail of Etude des performances zootechniques et sensibilité au virus de l’Influenza Aviaire H9N2 chez une race de poulet croisé à croissance intermediaire

Revue Marocaine des Sciences Agronomiques et Vétérinaires, Sep 15, 2021

Research paper thumbnail of Profil moléculaire et épidémiologique du virus de la bursite infectieuse aviaire circulant au Maroc entre 2013 et 2016

Revue Marocaine des Sciences Agronomiques et Vétérinaires, Sep 15, 2021

Research paper thumbnail of RETRACTED ARTICLE: Co-infection of turkeys with <i>Escherichia coli</i> (O78) and H6N1 avian influenza virus

We, the Editors and Publisher of the journal <i>Avian Pathology</i>, have retracted t... more We, the Editors and Publisher of the journal <i>Avian Pathology</i>, have retracted the following article: Sajid Umar, Maxence Delverdier, Mattias Delpont, Sakhia F.Z. Belkasmi, Angélique Teillaud, Céline Bleuart, Isabelle Pardo, Mohammed EL Houadfi, Jean-Luc Guérin & Mariette F. Ducatez 'Co-infection of turkeys with Escherichia coli (O78) and H6N1 avian influenza virus' (47:3, 2018) https://www.tandfonline.com/doi/full/10.1080/03079457.2018.1449942The above article has been retracted as, subsequent to publication, significant duplication has been found in content with the following unreferenced earlier published works: Qamar-un-Nisa, Muhammad Younus, Muti-ur-Rehman, Azhar Maqbool and Sajid Umar. 2017. Pathological Alterations during Co-Infection of Newcastle Disease Virus with Escherichia coli in Broiler Chicken. <i>Pakistan Journal of Zoology</i>, 50(2), pp 401–797, DOI: 10.17582/journal.pjz/2018.50.2.495.503Shahid Jaleel, Muhammad Younus, Asif Idre...

Research paper thumbnail of Evaluation semi-quantitative des lésions histopathologiques respiratoires chez la dinde moyennant un système de scoring lésionnel: Infection expérimentale par le virus de l’influenza aviaire faiblement pathogène H9N2

Revue Marocaine des Sciences Agronomiques et Vétérinaires, Sep 15, 2021

Research paper thumbnail of Avian Influenza a H9N2 Viruses in Morocco, 2018–2019

Viruses, 2022

Low pathogenic H9N2 avian influenza (LPAI H9N2) is considered one of the most important diseases ... more Low pathogenic H9N2 avian influenza (LPAI H9N2) is considered one of the most important diseases found in poultry (broiler, laying hens, breeding chickens, and turkeys). This infection causes considerable economic losses. The objective of this work was to monitor and assess the presence of avian influenza virus (AIV) H9N2 in eight different regions of Morocco using real-time RT-PCR, and to assess the phylogenetic and molecular evolution of the H9N2 viruses between 2016 and 2019. Field samples were collected from 108 farms suspected of being infected with LPAI H9N2 virus. Samples were analyzed using H9N2-specific real-time RT-PCR. Highly positive samples were subjected to virus isolation and seven isolates were fully sequenced. Low pathogenic H9N2 avian influenza virus was introduced in Morocco in 2016. We show that in 2018–2019, the virus was still present irrespective of vaccination status. Phylogenetic and molecular analyses showed mutations related to virulence, although our viru...

Research paper thumbnail of Les souches très virulentes du virus de la bursite infectieuse aviaire: Revue bibliographique et situation épidémiologique

Revue Marocaine des Sciences Agronomiques et Vétérinaires, 2020

Cette revue se focalise sur le virus très virulent de la bursite infectieuse aviaire (vvIBDV). Ce... more Cette revue se focalise sur le virus très virulent de la bursite infectieuse aviaire (vvIBDV). Ce virus est réparti dans le monde entier, causant des pertes économiques très considérable représentant une menace pour l'industrie de la volaille. L'émergence des formes aiguës de la maladie a radicalement changé l'épidémiologie de l'IBD. Bien que leur origine soit encore à l'étude, les vvIBDV se sont répandus dans le monde entier de manière explosive mais conservée. Cela pose la question de l'origine des vvIBDV, de la possibilité d'existence des réservoirs et de l'émergence possible de nouvelles lignées distinctes dans l'avenir. Il est devenu évident que les acides aminés dans la région hypervariable de la protéine virale VP2 constitue une base moléculaire de la variation antigénique, mais aucune mutation qui détermine la pathogénicité n'a été identifiée. Ces marqueurs moléculaires des souches vvIBDV doivent être considérés davantage comme une évo...

Research paper thumbnail of Esbl resistance APEC (eng) v2

Research paper thumbnail of Neurofibromatose segmentar: relato de caso

Anais Brasileiros De Dermatologia, 1999

Research paper thumbnail of Prevalence and molecular characterization of avian infectious bronchitis virus in poultry flocks in Morocco from 2010 to 2014 and first detection of Italy 02 in Africa

Avian pathology : journal of the W.V.P.A, 2015

The aim of this study was to investigate the prevalence and diversity of infectious bronchitis vi... more The aim of this study was to investigate the prevalence and diversity of infectious bronchitis virus (IBV) genotypes in poultry flocks in 16 areas of Morocco between 2010 and 2014. A total of 360 chicken flocks suspected of being infected by IBV were screened for the IBV N gene using real-time reverse transcriptase-polymerase chain reaction (RT-PCR). Flocks were classified into four groups according to their IBV vaccination programme. Group 1 contained unvaccinated birds. Group 2 received a single application of live H120 vaccine. Groups 3 and 4 birds received one or two booster vaccination(s), respectively, mostly using the H120 vaccine. The real-time RT-PCR results showed that 51.7% of the flocks were positive for the IBV genome with geographical disparities. Molecular characterization of IBV was performed on 50 RT-PCR positive samples by partially sequencing the S1 gene, including the hypervariable regions (nucleotides 705-1097). Two predominant genotypes were detected, with the ...

Research paper thumbnail of Moroccan

Phylogenetic analysis of avian infectious bronchitis virus S1 glycoprotein regions reveals emerge... more Phylogenetic analysis of avian infectious bronchitis virus S1 glycoprotein regions reveals emergence of a new genotype in