RESUMO
Infectious laryngotracheitis (ILT) is a severe respiratory disease, which causes high morbidity and mortality in affected birds. In our study, ILT were reported in 42 farms from nine governates over two years (20182020) that showed clinical signs of ILT including dyspnea, blood expectoration of, excessive lacrimation, rattling, conjunctivitis. The disease affected different chicken breeds and age groups despite vaccination with licensed and commonly used vaccines. Samples of larynx, trachea, lungs and air sacs were examined and collected for histopathological, ultrastructural, immunohistochemical examination and molecular detection. Gross examination of laryngeal and tracheal lumen revealed different types of exudate varied from catarrhal to fibrinonecotric, also pneumonia and airsacculitis were detected. Histopathological examination showed different alternation in larynx, trachea, lung and air sac as characteristic syncytial cells containing intranuclear inclusion body hanged in fibrinoheterphilic exudate that precent in laryngeal, tracheal, bronchial and parabronchial lumen and air sacs. Tracheal lesion scoring system was used to categorize the severity of lesion in different governates. Tracheal lesion score showed that 6.02%, 26.5%, 43.3% of the birds exhibited mild, moderate, and severe changes, respectively, while 24.18% of the birds exhibited very severe changes. Furthermore, severe cases were related to the Qalyubia , Fayoum then Sharkia Governorate. Moreover, immunohistochemistry was used to detect viral particles in syncytial cells, inflammatory cells beside epithelium of trachea and lung. Transmission electron microscopy enabled the detection of virus particles and demonstrated that heterophils could be infected. PCR targeting a region in the thymidine kinase gene and glycoprotein gJ gene confirmed the presence of infectious laryngotracheitis ILT virus-specific DNA. In conclusion, anatomopathological, immunohistochemical, molecular and ultrastructural findings showed increased of ILTV severity in Egypt. Larynx, trachea, lungs and air sac should be collected and examined that aid in diagnosis. Importance of good biosecurity level to be considered.
Assuntos
Animais , Aves Domésticas/anatomia & histologia , Aves Domésticas/imunologia , Aves Domésticas/microbiologia , Herpesvirus Galináceo 1/classificação , Herpesvirus Galináceo 1/patogenicidade , Imuno-Histoquímica/veterinária , Microscopia Eletrônica , Reação em Cadeia da PolimeraseRESUMO
Infectious laryngotracheitis (ILT) is a severe respiratory disease, which causes high morbidity and mortality in affected birds. In our study, ILT were reported in 42 farms from nine governates over two years (20182020) that showed clinical signs of ILT including dyspnea, blood expectoration of, excessive lacrimation, rattling, conjunctivitis. The disease affected different chicken breeds and age groups despite vaccination with licensed and commonly used vaccines. Samples of larynx, trachea, lungs and air sacs were examined and collected for histopathological, ultrastructural, immunohistochemical examination and molecular detection. Gross examination of laryngeal and tracheal lumen revealed different types of exudate varied from catarrhal to fibrinonecotric, also pneumonia and airsacculitis were detected. Histopathological examination showed different alternation in larynx, trachea, lung and air sac as characteristic syncytial cells containing intranuclear inclusion body hanged in fibrinoheterphilic exudate that precent in laryngeal, tracheal, bronchial and parabronchial lumen and air sacs. Tracheal lesion scoring system was used to categorize the severity of lesion in different governates. Tracheal lesion score showed that 6.02%, 26.5%, 43.3% of the birds exhibited mild, moderate, and severe changes, respectively, while 24.18% of the birds exhibited very severe changes. Furthermore, severe cases were related to the Qalyubia , Fayoum then Sharkia Governorate. Moreover, immunohistochemistry was used to detect viral particles in syncytial cells, inflammatory cells beside epithelium of trachea and lung. Transmission electron microscopy enabled the detection of virus particles and demonstrated that heterophils could be infected. PCR targeting a region in the thymidine kinase gene and glycoprotein gJ gene confirmed the presence of infectious laryngotracheitis ILT virus-specific DNA. In conclusion, anatomopathological, immunohistochemical, molecular and ultrastructural findings showed increased of ILTV severity in Egypt. Larynx, trachea, lungs and air sac should be collected and examined that aid in diagnosis. Importance of good biosecurity level to be considered.(AU)
Assuntos
Animais , Aves Domésticas/anatomia & histologia , Aves Domésticas/imunologia , Aves Domésticas/microbiologia , Herpesvirus Galináceo 1/classificação , Herpesvirus Galináceo 1/patogenicidade , Imuno-Histoquímica/veterinária , Reação em Cadeia da Polimerase , Microscopia EletrônicaRESUMO
The objective of this study was to determine how cytokine transcription profiles correlate with patterns of infectious laryngotracheitis virus (ILTV) replication in the trachea, Harderian gland, and trigeminal ganglia during the early and late stages of infection after intratracheal inoculation. Viral genomes and transcripts were detected in the trachea and Harderian gland but not in trigeminal ganglia. The onset of viral replication in the trachea was detected at day one post-infection and peaked by day three post-infection. The peak of pro-inflammatory (CXCLi2, IL-1ß, IFN-γ) and anti-inflammatory (IL-13, IL-10) cytokine gene transcription, 5 days post-infection, coincided with the increased recruitment of inflammatory cells, extensive tissue damage, and limiting of virus replication in the trachea. In contrast, transcription of the IFN-ß gene in the trachea remained unaffected suggesting that ILTV infection blocks type I interferon responses. In the Harderian gland, the most evident transcription change was the early and transient upregulation of the IFN-γ gene at 1 day post-infection, which suggests that the Harderian gland is prepared to rapidly respond to ILTV infection. Overall, results from this study suggest that regulation of Th1 effector cells and macrophage activity by Th1/2 cytokines was pertinent to maintain a balanced immune response capable of providing an adequate Th1-mediated protective immunity, while sustaining some immune homeostasis in preparation for the regeneration of the tracheal mucosa.
Assuntos
Citocinas/metabolismo , Glândula de Harder/metabolismo , Infecções por Herpesviridae/veterinária , Herpesvirus Galináceo 1/patogenicidade , Traqueia/metabolismo , Gânglio Trigeminal/metabolismo , Animais , Galinhas , Citocinas/genética , DNA , Regulação da Expressão Gênica/imunologia , Genoma Viral , Glândula de Harder/virologia , Infecções por Herpesviridae/metabolismo , Infecções por Herpesviridae/virologia , Herpesvirus Galináceo 1/fisiologia , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/metabolismo , Doenças das Aves Domésticas/virologia , RNA , Organismos Livres de Patógenos Específicos , Traqueia/virologia , Transcrição Gênica , Gânglio Trigeminal/virologia , Carga Viral , Virulência , Replicação ViralRESUMO
Avian Infectious laryngotracheitis (AILT) is a respiratory tract disease of great importance because it causes significant economic losses in the poultry industry around the world. It is caused by a Gallid herpesvirus type 1, a member of the genus Iltovirus. The target system for Avian Infectious Laryngotracheitis virus (AILTV) infections is the respiratory system, and the main organ in which the virus remains latent is the trigeminal ganglia. However, the virus has demonstrated tropism for other organs besides the respiratory tract. The main transmission routes are ocular and respiratory. Infected birds with clinical symptoms are main sources of transmission, but birds with latent infections, litter, and contaminated fomites may also transmit the virus. Clinical signs usually appear 6-12 days after natural exposure and may be moderate or severe. The causative agent of this disease can be propagated in chorioallantoic membrane (CAM) of developing chicken embryos and replicate in mature chicken kidney cells, as well as in a variety of epithelial chick embryo cells, such as kidneys, liver and lungs. There are several procedures for the diagnosis of ILT such as the observation of clinical signs, the detection of gross and histopathological lesions, and the use of molecular techniques, including RFLP, polymerase chain reaction (PCR), real-time PCR, and loop-mediated isothermal amplification. Vaccination with different types of vaccine provides a good expectation on disease control, such as vaccines produced in chicken-embryo-origin (CEO), tissue-culture-origin (TCO), and recombinant vaccines. However, in endemic areas, biosecurity measures and best management practices are important for the control of the disease. It is distributed worldwide and, in South America, it has been reported in Brazil, Peru, Ecuador, Bolivia, and Argentina causing great economic losses.(AU)
Assuntos
Animais , Epidemiologia , Herpesvirus Galináceo 1/fisiologia , Herpesvirus Galináceo 1/patogenicidade , Sistema Respiratório/patologia , Infecções por Herpesviridae/veterinária , Iltovirus/patogenicidade , Galinhas/fisiologia , Doenças Endêmicas/veterinária , /prevenção & controle , /estatística & dados numéricos , Vacinas contra Herpesvirus/uso terapêutico , Transmissão de Doença Infecciosa/veterinária , Controle de Doenças Transmissíveis , DiagnósticoRESUMO
Avian Infectious laryngotracheitis (AILT) is a respiratory tract disease of great importance because it causes significant economic losses in the poultry industry around the world. It is caused by a Gallid herpesvirus type 1, a member of the genus Iltovirus. The target system for Avian Infectious Laryngotracheitis virus (AILTV) infections is the respiratory system, and the main organ in which the virus remains latent is the trigeminal ganglia. However, the virus has demonstrated tropism for other organs besides the respiratory tract. The main transmission routes are ocular and respiratory. Infected birds with clinical symptoms are main sources of transmission, but birds with latent infections, litter, and contaminated fomites may also transmit the virus. Clinical signs usually appear 6-12 days after natural exposure and may be moderate or severe. The causative agent of this disease can be propagated in chorioallantoic membrane (CAM) of developing chicken embryos and replicate in mature chicken kidney cells, as well as in a variety of epithelial chick embryo cells, such as kidneys, liver and lungs. There are several procedures for the diagnosis of ILT such as the observation of clinical signs, the detection of gross and histopathological lesions, and the use of molecular techniques, including RFLP, polymerase chain reaction (PCR), real-time PCR, and loop-mediated isothermal amplification. Vaccination with different types of vaccine provides a good expectation on disease control, such as vaccines produced in chicken-embryo-origin (CEO), tissue-culture-origin (TCO), and recombinant vaccines. However, in endemic areas, biosecurity measures and best management practices are important for the control of the disease. It is distributed worldwide and, in South America, it has been reported in Brazil, Peru, Ecuador, Bolivia, and Argentina causing great economic losses.
Assuntos
Animais , Doenças Endêmicas/veterinária , Epidemiologia , Galinhas/fisiologia , Herpesvirus Galináceo 1/fisiologia , Herpesvirus Galináceo 1/patogenicidade , Iltovirus/patogenicidade , Infecções por Herpesviridae/veterinária , Sistema Respiratório/patologia , Controle de Doenças Transmissíveis , Diagnóstico , Transmissão de Doença Infecciosa/veterinária , Vacinas contra Herpesvirus/uso terapêuticoRESUMO
A laringotraqueíte infecciosa (LTI)é uma infecção virale de distribuição cosmopolita que acomete especialmente o trato respiratório superior e a conjuntiva das aves comerciais 21,33.O vírus da laringotraqueíte pertence ao gênero Iltovirus,família Herpesviridae e subfamília Herpesvirinae. O vírus é taxonomicamente identificado como Gallid herpesvírus 1 (GaHV-1).
Assuntos
Animais , Herpesvirus Galináceo 1/fisiologia , Herpesvirus Galináceo 1/patogenicidade , Diagnóstico Diferencial , Doenças Respiratórias/diagnóstico , Doenças Respiratórias/terapia , Galinhas/fisiologia , Patologia , Aves Domésticas/fisiologia , Aves Domésticas/virologia , Criação de Animais DomésticosRESUMO
A laringotraqueíte infecciosa (LTI)é uma infecção virale de distribuição cosmopolita que acomete especialmente o trato respiratório superior e a conjuntiva das aves comerciais 21,33.O vírus da laringotraqueíte pertence ao gênero Iltovirus,família Herpesviridae e subfamília Herpesvirinae. O vírus é taxonomicamente identificado como Gallid herpesvírus 1 (GaHV-1).
Assuntos
Animais , Diagnóstico Diferencial , Doenças Respiratórias/diagnóstico , Doenças Respiratórias/terapia , Galinhas/fisiologia , Herpesvirus Galináceo 1/fisiologia , Herpesvirus Galináceo 1/patogenicidade , Aves Domésticas/fisiologia , Aves Domésticas/virologia , Criação de Animais Domésticos , PatologiaRESUMO
Seventy-eight chickens from a very high poultry density (approximately eight million) region and twelve backyard chickens from neighboring areas were analyzed by histopathology and additional techniques for the presence of the infectious laryngotracheitis virus. The virus distribution was determined in different tissues using immunohistochemistry (IHC) and polymerase chain reaction (PCR). The disease was histopathologically diagnosed in 41.0% (32/78) of the commercial layers. Lesions were mainly characterized by syncytial cells with eosinophilic intranuclear inclusion body formed from the hyperplastic epithelium of the upper respiratory tract, primary and secondary bronchi, and conjunctiva. IHC showed 70% (21/30) positive signal in the larynx/trachea and, 53.8% (14/26) in the lungs, either in epithelial cells or syncytia. In the turbinates and paranasal sinuses, 29.6% (8/27) of samples showed positive signal. PCR detected the following gallid herpesvirus 1-positive percentages: conjunctiva 63.2% (31/49), lungs 57.6% (30/52), turbinates and paranasal sinuses 56% (28/50), and larynx/trachea 50% (39/78). IHC showed to be a useful additional tool for definitive ILT diagnosis, especially during the subacute phase of the disease when syncytial cells with intranuclear inclusion bodies are no longer observed. PCR using specific primers from ICP4 gene, generating a product of 237 base pairs, was sensitive for ILT diagnosis, and very useful for rapid detection of GaHV-1 in chickens. Fixed tissues allowing histopatological examination and detection of GaHV-1 by PCR, are a good option in areas where farms are located several hundred kilometers away from a diagnostic center, reducing problems with conservation of fresh samples and the risk of virus spread.
Assuntos
Animais , Aves Domésticas/anatomia & histologia , Aves Domésticas/imunologia , Herpesvirus Galináceo 1/imunologia , Herpesvirus Galináceo 1/patogenicidade , Imuno-Histoquímica , Reação em Cadeia da PolimeraseRESUMO
Seventy-eight chickens from a very high poultry density (approximately eight million) region and twelve backyard chickens from neighboring areas were analyzed by histopathology and additional techniques for the presence of the infectious laryngotracheitis virus. The virus distribution was determined in different tissues using immunohistochemistry (IHC) and polymerase chain reaction (PCR). The disease was histopathologically diagnosed in 41.0% (32/78) of the commercial layers. Lesions were mainly characterized by syncytial cells with eosinophilic intranuclear inclusion body formed from the hyperplastic epithelium of the upper respiratory tract, primary and secondary bronchi, and conjunctiva. IHC showed 70% (21/30) positive signal in the larynx/trachea and, 53.8% (14/26) in the lungs, either in epithelial cells or syncytia. In the turbinates and paranasal sinuses, 29.6% (8/27) of samples showed positive signal. PCR detected the following gallid herpesvirus 1-positive percentages: conjunctiva 63.2% (31/49), lungs 57.6% (30/52), turbinates and paranasal sinuses 56% (28/50), and larynx/trachea 50% (39/78). IHC showed to be a useful additional tool for definitive ILT diagnosis, especially during the subacute phase of the disease when syncytial cells with intranuclear inclusion bodies are no longer observed. PCR using specific primers from ICP4 gene, generating a product of 237 base pairs, was sensitive for ILT diagnosis, and very useful for rapid detection of GaHV-1 in chickens. Fixed tissues allowing histopatological examination and detection of GaHV-1 by PCR, are a good option in areas where farms are located several hundred kilometers away from a diagnostic center, reducing problems with conservation of fresh samples and the risk of virus spread.(AU)
Assuntos
Animais , Aves Domésticas/anatomia & histologia , Aves Domésticas/imunologia , Herpesvirus Galináceo 1/imunologia , Herpesvirus Galináceo 1/patogenicidade , Imuno-Histoquímica , Reação em Cadeia da PolimeraseRESUMO
At the end of 2002 and throughout 2003, there was a severe outbreak of infectious laryngotracheitis (ILT) in an intensive production area of commercial hens in the Sao Paulo State of Brazil. ILT virus was isolated from 28 flocks, and 21 isolates were genotyped by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) using four genes and eight restriction enzymes, and by partial sequencing of the infected cell protein 4 (ICP4) and thymidine kinase (TK) genes. Three groups resulted from the combinations of PCR-RFLP patterns: 19 field isolates formed Group I, and the remaining two isolates together with the chicken embryo origin (CEO) vaccine strains formed Group II. Group III comprised the tissue-culture origin (TCO) vaccine strain by itself. The PCR-RFLP results agreed with the sequencing results of two ICP4 gene fragments. The ICP4 gene sequence analysis showed that the 19 field isolates classified into Group I by RFLP-PCR were identical among themselves, but were different to the TCO and CEO vaccines. The two Group II isolates could not be distinguished from one of the CEO vaccines. The nucleotide and amino acid sequence analyses discriminated between the Brazilian and non-Brazilian isolates, as well as between the TCO and CEO vaccines. Sequence analysis of the TK gene enabled classification of the field isolates (Group I) as virulent and non-vaccine. This work shows that the severe ILT outbreak was caused by a highly virulent, non-vaccine strain.