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1.
Avian Dis ; 68(2): 99-111, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38885051

RESUMO

The continued circulation of infectious bursal disease virus (IBDV) in Egypt, despite the use of various vaccines, is a serious problem that requires continuous detection of IBDV. In the current study, real-time reverse transcriptase polymerase chain reaction testing of 100 diseased chicken flocks during 2017-2021 revealed the presence of very virulent IBDV (vvIBDV) in 67% of the flocks, non-vvIBDV in 11%, and a mixture of both vvIBDV and non-vvIBDV in 4%. Twenty-nine IBDV isolates were submitted for partial sequencing of the viral protein 2 hypervariable region (VP2-HVR), and 27 isolates were confirmed to be genogroup A3 (vvIBDV) with 96.3%-98.5% similarity to the global A3 (vvIBDV) and 88.9%-97% similarity to genogroup A1 vaccine strains. The remaining two isolates were non-vvIBDV and showed 91.1% and 100% identity with classical genogroup A1 strains, respectively. Furthermore, the sequence and phylogenetic analysis of VP1 (amino acids 33-254) of two selected isolates of A3, 5/2017 and 98/2021, clustered them as B2, vvIBDV-like, strains with high similarity (99.5%) to four Egyptian, 99% to Chinese and European, and 97.7% to Chinese and Polish vvIBDV isolates. Experimental infection of commercial broiler chickens with two vvIBDV-A3B2 isolates (5/2017 and 98/2021) showed no mortality despite typical tissue lesions, clear histopathological changes, and strong ELISA antibody response. Isolate 98/2021 was more pathogenic, as confirmed by histopathology, whereas isolate 5/2017 induced a stronger serological response. In conclusion, vvIBDV (A3B2) strains with two amino acid (aa) substitutions in VP1 as V141I and V234I as well as VP2 as Y220F and G254S are still circulating in Egypt.


Análisis de las secuencias genéticas y de la patogenicidad del virus de la enfermedad infecciosa de la bolsa de pollos en Egipto durante los años 2017­2021. La circulación continua del virus de la enfermedad infecciosa de la bolsa (IBDV) en Egipto, a pesar del uso de varias vacunas, continua siendo un problema serio que requiere la detección continua de este virus. En el presente estudio, se realizó una prueba de transcripción reversa y reacción en cadena de la polimerasa en tiempo real de 100 parvadas enfermas de pollos durante los años 2017­2021 y reveló la presencia de virus muy virulentos (vvIBDV) en el 67% de las parvadas, otros tipos diferentes a los muy virulentos en el 11%, y una mezcla de virus muy virulentos y otros tiposen un 4% de las parvadas. Se enviaron veintinueve aislados del virus de la enfermedad infecciosa de la bolsa para la secuenciación parcial de la región hipervariable de la proteína viral 2 (VP2-HVR), y se confirmó que 27 aislados pertenecían al genogrupo A3 (vvIBDV) con una similitud del 96.3% al 98.5% con el genogrupo A3 global (vvIBDV) y de 88.9% a 97% de similitud con las cepas vacunales del genogrupo A1. Los dos aislamientos restantes no resultaron ser muy virulentos y mostraron un 91.1% y un 100% de identidad con las cepas clásicas del genogrupo A1, respectivamente. Además, la secuencia y el análisis filogenético de la proteina VP1 (aminoácidos 33-254) de dos aislados seleccionados de genogrupo A3, 5/2017 y 98/2021, los agruparon como cepas B2, similares a virus muy virulentos, con alta similitud (99.5%) con cuatro aislamientos de Egipto, con similitud de 99% con aislados chinos y europeos, y de 97.7% con aislados muy virulentos chinos y polacos. La infección experimental de pollos de engorde comerciales con dos aislados muy virulentos tipo A3B2 (5/2017 y 98/2021) no mostró mortalidad a pesar de las lesiones tisulares típicas, los cambios histopatológicos claros y la fuerte respuesta de anticuerpos por ELISA. El aislado 98/2021 fue más patógeno, según lo confirmado por histopatología, mientras que el aislado 5/2017 indujo una respuesta serológica más fuerte. En conclusión, las cepas muy virulentas (A3B2) con dos sustituciones de aminoácidos (aa) en la proteina VP1 como V141I y V234I, así como en VP2 tales como Y220F y G254S, todavía circulan en Egipto.


Assuntos
Infecções por Birnaviridae , Galinhas , Vírus da Doença Infecciosa da Bursa , Filogenia , Doenças das Aves Domésticas , Animais , Vírus da Doença Infecciosa da Bursa/genética , Vírus da Doença Infecciosa da Bursa/patogenicidade , Infecções por Birnaviridae/veterinária , Infecções por Birnaviridae/virologia , Infecções por Birnaviridae/epidemiologia , Doenças das Aves Domésticas/virologia , Doenças das Aves Domésticas/epidemiologia , Egito/epidemiologia , Virulência
3.
Front Vet Sci ; 9: 963199, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36304412

RESUMO

Infection with fowl adenoviruses (FAdVs) can result in a number of syndromes in the production of chicken, including inclusion body hepatitis (IBH), hepatitis-hydropericardium syndrome (HHS), and others, causing enormous economic losses around the globe. FAdVs are divided into 12 serotypes and five species (A-E; 1-8a and 8b-11). Most avian species are prone to infection due to the widespread distribution of FAdV strains. The genus aviadenovirus, which is a member of the adenoviridae family, is responsible for both IBH and HHS. The most popular types of transmission are mechanical, vertical, and horizontal. Hepatitis with basophilic intranuclear inclusion bodies distinguishes IBH, but the buildup of translucent or straw-colored fluid in the pericardial sac distinguishes HHS. IBH and HHS require a confirmatory diagnosis because their clinical symptoms and postmortem abnormalities are not unique to those conditions. Under a microscope, the presence of particular lesions and inclusion bodies may provide clues. Traditional virus isolation in avian tissue culture is more delicate than in avian embryonated eggs. Additionally, aviadenovirus may now be quickly and precisely detected using molecular diagnostic tools. Preventive techniques should rely on efficient biosecurity controls and immunize breeders prior to production in order to protect progeny. This current review gives a general overview of the current local and global scenario of IBH, and HHS brought on by FAdVs and covers both their issues and preventative vaccination methods.

4.
Poult Sci ; 101(4): 101684, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35168162

RESUMO

Globally, several studies have investigated the utilization and efficacy of promising medicinal herbal plants to enhance livestock and poultry production. The most commonly investigated phytobiotics in broiler ration were oregano, garlic, thyme, rosemary, black pepper, hot red pepper (HRP), and sage. Phytobiotics are classified on the basis of the medicinal properties of plants, their essential oil extracts, and their bioactive compounds. The majority of bioactive compounds in plants are secondary metabolites, such as terpenoids, phenolic, glycosides, and alkaloids. The composition and concentrations of these bioactive constitutes vary according to their biological factors and manufacturing and storage conditions. Furthermore, HRP is one of the most important and widely used spices in the human diet. Capsicum annum, that is, HRP, is a species of the plant genus Capsicum (pepper), which is a species native to southern North America and northern South America and is widely grown and utilized for its fresh or cooked fruits. Moreover, these fruits may be used as dried powders or processed forms of oleoresins. Researches have proven that C. annuum is the only plant that produces the alkaloid capsaicinoids. Approximately 48% of its active substances are capsaicin (8-methyl-N-vanillyl-6-nonemide), the main active compound responsible for the intense effects of HRP varieties and the main component inducing the hot flavor. This review aimed to highlight the effects of HRP as a phytobiotic in broiler nutrition and its mode of action as a possible alternative to antibiotics and clarify its impact on broiler and layer productivity.


Assuntos
Capsicum , Animais , Antibacterianos , Galinhas , Aves Domésticas , Pós
5.
Avian Dis ; 65(3): 407-413, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34427415

RESUMO

Despite the vast Egyptian poultry production, scanty information is available concerning the infection of haemprotozoan parasites as pathogens in commercial broilers. In the present study, we provided the first detection of leucocytozoonosis in five broiler chicken flocks in El-Beheira Egyptian governorate. Despite the low mortality rates in the affected flocks (0.3%-1% as a 5-day mortality), severe postmortem (hemorrhagic spots and scars) and histopathologic lesions appeared in different organs including skeletal muscles, liver, kidney, pancreas, abdominal cavity, and bursa of Fabricius. Evaluation of blood smears revealed gametocytes in erythrocytes and leukocytes. Conventional reverse transcriptase-PCR and partial sequence analysis of mitochondrial cytochrome oxidase b gene detected Leucocytozoon caulleryi. GenBank accession numbers of the five Egyptian L. caulleryi isolates were obtained. The five L. caulleryi were 99.9% identical to each other and 99.14% similar to the L. caulleryi mitochondrial DNA gene of Asian strains from India, Japan, Malaysia, South Korea, Taiwan, and Thailand.


Leucocytozoon caulleryi en parvadas de pollos de engorde: detección clínica, hematológica, histopatológica y molecular. A pesar de la vasta producción avícola en Egipto, se dispone de escasa información sobre la infección de parásitos hemoprotozoarios como patógenos en pollos de engorde comerciales. En el presente estudio, se proporciona la primera detección de leucocitozoonosis en cinco parvadas de pollos de engorde en la gobernación egipcia de El-Beheira. A pesar de las bajas tasas de mortalidad en las parvadas afectadas (0.3% -1% como mortalidad de 5 días), aparecieron graves lesiones post mortem (manchas hemorrágicas y cicatrices) e histopatológicas en diferentes órganos, incluidos músculo esquelético, hígado, riñón, páncreas, cavidad abdominal y bolsa de Fabricio. La evaluación de los frotis de sangre reveló gametocitos en eritrocitos y leucocitos. Mediante un método de transcripción reversa con PCR convencional y el análisis parcial de secuencias del gene del citocromo oxidasa b mitocondrial se detectó Leucocytozoon caulleryi. Se obtuvieron los números de acceso de la base de datos GenBank de los cinco aislados de los L. caulleryi egipcios. Los cinco L. caulleryi eran 99.9% idénticos entre sí y 99.14% similares al gene del ADN mitocondrial de L. caulleryi de cepas asiáticas de India, Japón, Malasia, Corea del Sur, Taiwán y Tailandia.


Assuntos
Haemosporida , Doenças das Aves Domésticas , Infecções Protozoárias em Animais , Animais , Galinhas , Citocromos b/genética , Haemosporida/genética
6.
Environ Sci Pollut Res Int ; 28(18): 22241-22264, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33733422

RESUMO

Diseases negatively impact the environment, causing many health risks and the spread of pollution and hazards. A novel coronavirus, severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) has led to a recent respiratory syndrome epidemic in humans. In December 2019, the sudden emergence of this new coronavirus and the subsequent severe disease it causes created a serious global health threat and hazards. This is in contrast to the two aforementioned coronaviruses, SARS-CoV-2 (in 2002) and middle east respiratory syndrome coronavirus MERS-CoV (in 2012), which were much more easily contained. The World Health Organization (WHO) dubbed this contagious respiratory disease an "epidemic outbreak" in March 2020. More than 80 companies and research institutions worldwide are working together, in cooperation with many governmental agencies, to develop an effective vaccine. To date, six authorized vaccines have been registered. Up till now, no approved drugs and drug scientists are racing from development to clinical trials to find new drugs for COVID-19. Wild animals, such as snakes, bats, and pangolins are the main sources of coronaviruses, as determined by the sequence homology between MERS-CoV and viruses in these animals. Human infection is caused by inhalation of respiratory droplets. To date, the only available treatment protocol for COVID-19 is based on the prevalent clinical signs. This review aims to summarize the current information regarding the origin, evolution, genomic organization, epidemiology, and molecular and cellular characteristics of SARS-CoV-2 as well as the diagnostic and treatment approaches for COVID-19 and its impact on global health, environment, and economy.


Assuntos
COVID-19 , Coronavírus da Síndrome Respiratória do Oriente Médio , Animais , Surtos de Doenças , Meio Ambiente , Humanos , SARS-CoV-2
7.
Avian Dis ; 64(4): 536-541, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33570106

RESUMO

The prevalence of Gallibacterium anatis in poultry production has increased over the last two decades. However, only a few studies have explored the pathogenicity of this bacterium in commercial layer chickens. This trial studied the aspects of the pathogenicity of a Gallibacterium anatis biovar haemolytica local Egyptian isolate (previously registered as strain B14 with GenBank accession no. KJ026147). We used 500 base pairs of a 16S ribosomal RNA gene and the 16S-23S ribosomal RNA intergenic spacer, partial sequence in an experimental infection trial in commercial White Shaver layer chickens aged 19 wk. The hens were divided into three groups of 40 birds each. The hens in Groups 1 and 2 were experimentally infected through the intranasal (IN) and intravenous (IV) routes, respectively, with a dose of 0.2 ml/bird containing 1.2 × 109 colony-forming units/ml. In contrast, Group 3 was kept as a noninfected control group. Both IN and IV infections resulted in a delayed egg laying for 1 wk and a significant (P ≤ 0.05) drop in egg production by 7.81% and 10.28% compared with the control group over 7 wk. Severe lesions in the form of hemorrhagic pneumonia, catarrhal tracheitis, ovarian follicle and oviductal regression, and septicemia were evident on necropsy, demonstrating the pathogenicity of G. anatis as a primary pathogen.


Assuntos
Galinhas , Doenças Ovarianas/veterinária , Infecções por Pasteurellaceae/veterinária , Pasteurellaceae/fisiologia , Pasteurellaceae/patogenicidade , Doenças das Aves Domésticas/patologia , Doenças Respiratórias/veterinária , Animais , Feminino , Doenças Ovarianas/microbiologia , Doenças Ovarianas/patologia , Doenças Ovarianas/fisiopatologia , Pasteurellaceae/genética , Infecções por Pasteurellaceae/microbiologia , Infecções por Pasteurellaceae/patologia , Infecções por Pasteurellaceae/fisiopatologia , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/fisiopatologia , Doenças Respiratórias/microbiologia , Doenças Respiratórias/patologia , Doenças Respiratórias/fisiopatologia , Sepse/microbiologia , Sepse/patologia , Sepse/fisiopatologia , Sepse/veterinária
8.
Animals (Basel) ; 9(6)2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31185682

RESUMO

Newcastle disease is an acute fatal disease of poultry. The aim of this study was to determine the dynamics of the transmission of avian avulavirus (velogenic viscerotropic Newcastle disease-genotype VIId) from either intramuscularly (IM)- or intranasally (IN) infected 8-week-old Egyptian Baladi pigeons in contact with commercial Arbor Acres broiler chickens (4 weeks of age). The mortality of IM infected chickens and pigeons was 10/10 for chickens and 8/15 for pigeons, while the mortality of IN infected chickens and pigeons was 7/10 for chickens and only 1/15 for pigeons. The concentration of viral shedding in the oropharynx was higher than that in the cloaca for both IN and IM infected pigeons. Pigeons infected IN continued shedding the virus from the oropharynx from the 4th day post-infection (dpi) up to the 16th dpi, while IM infected pigeons stopped oropharyngeal shedding at the 11th dpi. Chickens in contact with infected pigeons developed severe respiratory, digestive and nervous signs. The mortality rates in chickens in contact with IM and IN infected pigeons were 2/5 and 3/5, respectively. Chickens in contact with IM infected pigeons showed higher viral shedding titres in both the oropharynx and cloaca than chickens in contact with pigeons infected IN. In conclusion, free-range pigeons are considered an efficient carrier and transmitter of NDV-VIId compared to commercial broiler chickens raised in open houses.

9.
Poult Sci ; 98(10): 4441-4448, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31111928

RESUMO

This work was designed to study the dynamics of transmission of Newcastle disease virus (NDV), genotype VIId, from Muscovy ducks (Cariana moscata) infected either by intramuscular (IM) or intranasal (IN) inoculation, to in-contact broiler chickens (Gallus gallus). IM-infected Muscovy ducks (G1d) exhibited only 5% mortality, and the concentration of virus shed from the cloaca was greater and for longer period than virus shed from the trachea. In contrast, IN-infected ducks (G2d) exhibited no mortality, and virus shedding from the trachea was higher than that from the cloaca starting from 4 days post infection (dpi) and continued up to 16 dpi, while in IM-infected ducks (G1d), tracheal shedding stopped at 11 dpi. Chickens in contact with IM-infected and IN-infected ducks, G1c and G2c, respectively, not only developed severe clinical symptoms and death (80% and 20% mortality, respectively), but also shed the virus at higher concentrations than infected ducks. G1c chickens had higher viral shedding titers in both the trachea and cloaca than G2c chickens until 11 dpi. All broiler chickens infected by IM route (G3c) died, while the IN route of infection resulted in lower mortality (70%) in G4c. Generally, all IM-infected birds produced an earlier and higher level of NDV hemagglutination inhibition (HI) antibody titer, along with higher rates and shorter periods of viral shedding than those infected by the intranasal route. Our conclusion is that Muscovy ducks are efficient carriers of NDV-genotype VIId and transmit the virus to contact chickens.


Assuntos
Galinhas , Patos , Doença de Newcastle/transmissão , Vírus da Doença de Newcastle/imunologia , Doenças das Aves Domésticas/transmissão , Animais , Genótipo , Doença de Newcastle/virologia , Vírus da Doença de Newcastle/genética , Doenças das Aves Domésticas/virologia
10.
BMC Vet Res ; 14(1): 358, 2018 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-30458777

RESUMO

BACKGROUND: H9N2 avian influenza virus is endemic in Egyptian poultry flocks. The role of the live viral vaccines such as LaSota in exaggeration of the clinical picture of H9N2 infection under field conditions is significantly important leading to severe economic losses due to higher mortality and lower growth performance. This experiment was designed to identify the possible interaction between experimental infection with H9N2 virus and NDV live vaccine (LaSota strain) in broiler chickens. Six groups each of 20 broiler chicks were used. Three groups (G1-3) were infected with H9N2 and vaccinated with LaSota, 3 days before, at the same day or 3 days post vaccination (dpv), while the remaining groups (G4-6) were non-vaccinated infected, vaccinated non-infected and non-vaccinated non-infected. RESULTS: The highest mortality rate (37.5%) was noticed in chickens of G1 (H9N2 infected 3 days prior LaSota vaccination). Also, this bird group had the most severe clinical signs, histopathological lesions and the longest viral shedding for 9 days post infection (dpi). In the 2nd and 3rd groups, the mortality rate was the similar (31.2%) with less pronounced clinical signs, histopathological lesions and H9N2 shedding was for only 6 dpi with the least shedding quantity in chickens of G3. The control non-vaccinated infected chickens (G4) had 18.7% mortality with the least degree of clinical signs, lesions and the highest viral shedding quantity but only for 6 dpi. At 35 days of age, there was a statistical significant decrease (P < 0.05) in chicken's body weight of all H9N2 infected groups from G1 to G4 compared to non-infected control groups, G5 and G6 respectively. CONCLUSION: It was clear that laSota vaccination significantly affect H9N2 infection in broiler chickens regarding clinical signs, mortality rate, lesions, performance and viral shedding.


Assuntos
Vírus da Influenza A Subtipo H9N2 , Influenza Aviária/imunologia , Vírus da Doença de Newcastle/imunologia , Vacinas Virais/imunologia , Animais , Galinhas/imunologia , Galinhas/virologia , Vírus da Influenza A Subtipo H9N2/imunologia , Influenza Aviária/mortalidade , Influenza Aviária/prevenção & controle , Influenza Aviária/virologia , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Vacinas Virais/farmacologia , Eliminação de Partículas Virais
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