Outbreaks Of Inclusion Body Hepatitis Research Articles

Pathological and phylogenetic characterization of a rare fowl adenovirus (FAdV-8b) associated with inclusion body hepatitis in naturally infected Meleagris gallopavo.

Adenoviruses are a diverse group of viruses that can cause a variety of diseases in poultry, including respiratory and gastrointestinal infections. In turkeys (Meleagris gallopavo), adenoviruses commonly cause hemorrhagic enteritis and, rarely, inclusion body hepatitis. In this study, we investigated fowl adenoviruses (FAdVs) circulating in turkeys in Egypt. Following clinical examination of 500 birds, a portion of the hexon gene was amplified from four out of 50 samples from diseased birds (8%), and one amplicon that produced a strong band was selected for sequencing. Molecular and phylogenetic analysis revealed that the virus in that sample belonged to serotype FAdV-8b. Histopathological and immunohistochemical examinations of prepared tissue sections were performed to confirm the pathological findings. Diseased birds exhibited ruffled feathers, low body weight, a crouching posture, and diarrhea. Gross examination revealed petechial hemorrhage on the spleen, swollen pale liver, and congested intestine. Microscopic examination revealed the presence of eosinophilic and basophilic intranuclear inclusion bodies, nuclear pyknosis, and apoptotic bodies in the liver, congestion, hemorrhage, and fibrosis in the lungs, and desquamation of enterocytes. The presence of viral antigens in the liver, lungs, and intestine was confirmed by immunohistochemistry. To our knowledge, this is the first report of the characterization of an outbreak of inclusion body hepatitis in turkeys (hybrid converter breeds) due to FAdV-8b in Egypt. This finding raises an epidemiological alarm, necessitating further studies, including full-genome sequencing, to trace the virus's origin and genetic diversity.

Fowl Aviadenovirus (FAdV-11) as the causative agent of a vertical outbreak of inclusion body hepatitis in commercial broiler breeders in Brazil

Inclusion body hepatitis (IBH), caused by Fowl Aviadenovirus (FAdV), is a significant disease affecting chickens worldwide. FAdV-11 associated with IBH was identified in 9-day-old commercial broiler breeders in Brazil. The chicks exhibited a sudden increase in daily mortality, accompanied by nonspecific clinical signs, in one house on the farm. The cumulative mortality rate reached 11.13 % by 15 days of age. Macroscopically, the liver was markedly enlarged and pale red with a distinct lobular pattern. Histologically, the liver showed mild to severe multifocal coalescent vacuolar degeneration and necrosis, with hepatocyte nuclei diffusely enlarged and containing large basophilic inclusion bodies. Additionally, the heart exhibited a diffuse, moderate infiltration of lymphocytes and plasma cells, with focal thrombosis in the epicardium. FAdV was detected in liver samples using specific primers for the hexon gene (52 K-fw and 52 K-rv) in a polymerase chain reaction (PCR) assay. Sequencing of the hypervariable region of this gene (Hex L1) for phylogenetic analysis revealed FAdV-D species serotype 11. To our knowledge, this is the first report of FAdV-D serotype 11 as the causative agent of a vertical outbreak of inclusion body hepatitis in broiler breeders in Brazil.

Studying an outbreak of inclusion body hepatitis in broilers in Nineveh governorate, Iraq

The aim of this study was to provide field outbreaks data with FAdVs in Ninevah governorate to emphasize the importance of the disease due to high mortality and production losses. A total of 729,500 broilers collected from 64 flocks at 14 different locations in Nineveh governorate during the second half of 2020. were included in this study. Histopathological changes of the liver in infected birds have been studied. Molecular identification of FAdV was accomplished by DNA extraction from liver samples using DNeasy Tissue Kit. Results reviled that there were 51892 mortalities representing 7.11%. It was noted that the broiler flocks were infected during their 2nd-6th weeks of age, being the highest in the 5th week of age. Decreased mortality was detected from July to December. being 11.3, 7.91, 7.08, 6.38, 5.94 and 4.95%, respectively. Microscopical examination of the liver manifested the pathognomonic presence of eosinophilic intranuclear inclusion bodies related to the disease. PCR findings revealed positive results of FAdVs. It could be concluded that the environmental stress and immunosuppressive agents could contribute to the percentage and duration of mortalities in broiler flocks.

Genetic diversity of fowl adenovirus serotype 8b isolated from cases of inclusion body hepatitis in commercial broiler chickens

Inclusion body hepatitis (IBH) is a devastating disease of chickens caused by Fowl adenovirus (FAdV) and molecular studies of hexon gene is important for classification of FAdV isolates, epidemiology of IBH infection and development of effective control strategy. The objective of the study was to molecularly characterize FAdV isolates obtained from the field outbreaks of IBH in broiler chicken from 2017 to 2019. Liver and gizzard samples named UPM1701, UPM1801, UPM1802, UPM1901 and UPM1902 were collected and processed for FAdV detection and characterization by PCR. Swollen, necrotic and haemorrhagic liver; erosion of koilin layer of gizzard and enlargement of the proventriculus were observed. The samples were positive for FAdV with 98% to 100% identical to serotype 8b reference strains based on NCBI Blast. Thirty-one nucleotide changes that produced 10 amino acid substitutions were observed in L1 loop region of UPM1701, UPM1901 and UPM1902 isolates. All isolates clustered together with FAdV 8b reference strains and shared common ancestor with UPM1137E2 and UPM04217. Gizzard erosion in FAdV 8b infection is not common and conciding with mutations indicate evolving novel pathogenicity. These mutations could have effect on the epidemiology of IBH and be useful in designing effective prevention and control strategy.

Pathogenicity of field strain of fowl aviadenovirus serotype 11 isolated from chickens with inclusion body hepatitis in Morocco.

Outbreaks of inclusion body hepatitis have emerged in Morocco since 2013 and has resulted in significant economic losses to poultry farms. Three isolates of the causative virus, Fowl adenonovirus (FAdV)were characterized from chickens with IBH, but their pathogenicity has never been investigated. In this work, the pathogenicity of an isolate FAdV 11 (MOR300315 strain) was evaluated by inoculating a group of 40 SPF chickens at 3 days of age by oral route. A group of 40 chicks injected with phosphate-buffered saline solution was used as a control group. The infected chickens showed decreased weight gain from 3dpi. Necropsy displayed pallor and enlargement in liver, swelling and slight hemorrhage in kidney and spleen at 6 dpi. Histopathological changes were mainly characterized by severe and extensive hepatic necrosis associated with the presence of basophilic intra-nuclear inclusion bodies within hepatocytes. The FAdV was reisolated in chicken embryo fibroblast cell culture from liver tissue homogenate of infected chicken from 3 to 6 dpi. Viral DNA was detected by PCR in liver, kidney, spleen and cloacal swabs from 3 to 13 dpi. Antibody response against inoculated FAdV was appeared from 9 dpi. These results confirmed that the FAdV 11 strain is pathogenic in chicken. This study is the first experimental infection of FAdV 11 in chicken in Morocco, which increase our understanding of its pathogenicity in chickens and indicate that preventive measures against FAdV infection in poultry farms should be implemented in Morocco.

Molecular epidemiology of fowl adenoviruses in Greece

Outbreaks of inclusion body hepatitis (IBH) and adenoviral gizzard erosion have been anecdotally reported in Greece since approximately 2011. However, a relevant increase in clinical outbreaks compatible with IBH has been described since 2014. Unfortunately, with limited exceptions, only serological assays were performed, and involved strains were not properly characterized. In the present study, 35 outbreaks were investigated in the period between July 2017 and February 2018 in Greece. In addition to clinical and histopathological diagnosis, fowl adenovirus (FAdV) presence was investigated by PCR and sequencing. Thirty-four out of 35 samples tested FAdV positive. Twenty-nine (85.29%) and 5 (14.71%) strains were classified as FAdV-E and FAdV-D, respectively. Fowl adenovirus-E strains were genetically homogeneous and formed an independent cluster of Greek-only sequences, including the sole previously available sequence, suggesting the prolonged circulation of this species in Greece. On the contrary, FAdV-D strains were more heterogeneous and closely related to strains sampled in other European countries, testifying the occurrence of multiple introduction events. The evaluation of phylogenetic relationships, geographic clustering, age of infection, and origin of the broiler breeder flocks suggests that both vertical and horizontal transmission are important in FAdV epidemiology in Greece and highlights the limited efficacy of currently implemented control measures. Of note, a significantly higher mortality was observed in precociously infected flocks, likely because of the higher susceptibility of younger animals. This evidence stresses the need of preventing vertical and/or early infection to limit the economic impact of adenovirus-induced diseases.

Characterisation of Fowl Adenovirus (FAdV-8b) Strain Concerning the Geographic Analysis and Pathological Lesions Associated with Inclusion Body Hepatitis in Broiler Flocks in Turkey.

IntroductionFowl adenovirus can cause important diseases in chickens such as inclusion body hepatitis, hepatitis hydropericardium syndrome, and gizzard erosion and ulceration. Inclusion body hepatitis has been regularly reported from many countries. This is the first case report from Turkey, describing an outbreak of inclusion body hepatitis in broiler farms due to fowl adenovirus-8b (FAdV-8b).Material and MethodsBroiler flocks with mortality about 10% were visited in Turkey, and necropsy was performed on dead birds. Samples were subjected to PCR assay to detect FAdV and other viral pathogens. After sequencing, phylogenetic analysis was performed and the nucleotide sequences of hexon genes were compared with the FAdV sequences data available in GenBank.ResultsClinical signs such as anorexia, depression, ruffled feathers, huddling, and greenish diarrhoea were observed. Mortality started at the 8th day of age and ranged from 10% to 14%. Necropsy showed severe hepatitis, jaundice, and pancreatitis. The main necropsy findings included a pale, enlarged, haemorrhagic, and friable liver along with swollen and haemorrhagic kidneys and spleen. PCR and sequence analysis revealed the presence of fowl adenovirus serotype 8b (FAdV-E).ConclusionThis is the first report on characterisation and the pathological lesions associated with FAdV in broilers in Turkey. Our findings suggest that FAdV strains could be an emerging pathogen in Turkish broilers and could actively contribute to hepatitis and immunosuppression.

An efficient fiber-based ELISA for detection of antibody against fowl adenovirus serotypes 7 and 8.

An outbreak of inclusion body hepatitis caused by fowl adenovirus serotype 8 (FAdV-8) has caused significant economic losses in the poultry industry worldwide. However, a rapid serology test kit specific to FAdV-8 is not available to date. We developed a fiber-based ELISA using the purified GST-fiber of FAdV-8 as coating antigen to measure antibodies against FAdV-8. Specificity analysis showed that our ELISA could react with sera against FAdV-7, -8a, and -8b, but not with sera against the other pathogens tested. Moreover, detection of positive sera with our ELISA had 83% and 94% agreement with an indirect immunofluorescence assay (IFA) and a commercial ELISA from BioChek, respectively. Our ELISA was also effective in the detection of antibodies against FAdV-8 in sera from both experimentally infected and clinically vaccinated chickens. Our FAdV-8 fiber-based ELISA can be a valuable tool to specifically and sensitively detect antibodies against FAdV-7 and/or -8 in infected or vaccinated chickens.

Isolation and molecular characterization of fowl aviadenovirus associated with inclusion body hepatitis from poultry in Banten and West Java, Indonesia.

Background and Aim:Fowl avidenoviruses (FAdVs) are generally considered ubiquitous, but certain serotypes and strains are known to be associated with primary diseases, such as inclusion body hepatitis (IBH). Since 2018, the outbreak of IBH has been reported in part provinces of Indonesia. This study aimed to isolate and molecularly characterize the FAdV from Banten and West Java Provinces of Indonesia and described the phylogenetic relationship with the FAdV that has been characterized in other countries.Materials and Methods:A total of 25 FAdV archive samples have been collected from January to August 2019 from clinical cases of FAdV infection in Banten and West Java Provinces, Indonesia. Collected samples were inoculated in 10-day-old specific-pathogenic-free chicken embryonated eggs. Hexon gene of FAdV was detected using polymerase chain reaction (PCR) with a primer set from previous study. To gain a better understanding of the FAdV genetic properties and construct the phylogeny tree, the PCR products were sequenced and subjected to a BLAST search and inferred using the neighbor-joining method by bootstrap test 1000×.Results:FAdV-D and FAdV-E are present in Banten, Indonesia. The phylogenetic analysis of 850 nucleotides that encode 289 amino acid of the partial hexon gene shows that the isolates Broiler/MSL/Ciputat-149/18, Broiler/MSL/Lebak-151/18, and Broiler/MSL/Ciputat-29/19 have 100% homology with FAdV-E TR/BVKE/R/D-1 from Turkey, whereas the isolates Layer/MSL/Ciputat-20/19 and Broiler/MSL/Ciputat-30/19 have 100% homology with FAdV-D strain 685 from Canada.Conclusion:The present study provides updates of the circulating FAdV in commercial poultry flocks in Banten and West Java Provinces, Indonesia. Since the FAdV vaccine was unavailable in Indonesia, this result might be used as guidance to select a proper FAdV vaccine strain. Our result indicates that at least two FAdV species were circulating among poultry in Banten and West Java Provinces, Indonesia; they are FAdV-D and FAdV-E.

First report of fowl aviadenovirus serotypes FAdV-8b and FAdV-11 associated with inclusion body hepatitis in commercial broiler and broiler-breeder flocks in Turkey.

Inclusion body hepatitis (IBH), hydropericardium syndrome (HS), and gizzard erosion (GE) are all economically important diseases in the poultry industry worldwide and are all caused by fowl aviadenovirus (FAdV). It is important to identify the serotype of the virus to differentiate these diseases. In the present study, a total of six recent FAdV serotypes were isolated and identified in broiler and broiler-breeder flocks in Izmir, Manisa, and Aydın provinces of the Aegean region of Turkey between January and March 2019. The viruses were isolated from livers and pooled organs of chickens using primary chicken embryo kidney cell cultures (CEKC). Virus isolates were identified by PCR amplification of the loop 1 (L1) variable region of the hexon gene followed by Sanger sequencing. Sequence analysis revealed the presence of both FAdV-D (serotype 11) and FAdV-E (serotype 8b). The viruses that were isolated were associated withIBH, which is typically characterized by gross lesions such as enlarged and pale yellow liver with multiple petechial hemorrhages. Histopathological examination also showed necrotizing hepatitis with intranuclear inclusion bodies in hepatocytes. This study is the first report of the isolation and identification of FAdV serotypes associated with IBH in commercial broilers and broiler-breeder flocks in Turkey. The results of sequence analysis showed that FAdV-8b and FAdV-11 were the circulating serotypes that caused recent field outbreaks of IBH in the Aegean region between January and March, 2019.

Caracterización molecular del adenovirus aviar en pollos comerciales del Ecuador

El Adenovirus Aviar del grupo I (FAdV-I), es considerado como un patógeno de mucha importancia en la industria avícola en el Ecuador y a nivel mundial. La Hepatitis por Cuerpos de Inclusión (IBH) y el Síndrome del Hidropericardio (HPS), son las principales enfermedades asociadas a este virus, y a pesar de ser un agente etiológico que por lo general se encuentra relacionado a enfermedades inmunodepresoras como Anemia Infecciosa de las Aves o la enfermedad de Gumboro, recientes estudios han demostrado la actividad patológica del FAdV-I como responsable primario de estas enfermedades. Desde la década de 1990, se reportaron varios brotes importantes de IBH y HPS en muchos países de América Latina incluyendo el Ecuador, logrando identificar principalmente al serotipo 4 del FAdV-I como agente causal de estos brotes. El objetivo de este estudio fue determinar por métodos moleculares como la Reacción en Cadena de la Polimerasa (PCR), la presencia de los serotipos del FAdV-I que se encuentran circulando en granjas de aves comerciales en Ecuador. Fueron colectados diferentes órganos de aves con problemas entéricos en la zona norte del Ecuador, y posteriormente impregnados en tarjetas FTA para su transporte y procesamiento. 4/13 (30,8%) muestras fueron positivas a FAdV-I y mediante el secuenciamiento y análisis bioinformático del ADN amplificado por la PCR, se caracterizaron los serotipos 6 y 11 del FAdV-I. Estos datos nos demuestran la variedad de serotipos presentes en granjas avícolas del Ecuador y que podrían estar influenciando en el estado sanitario de la industria avícola del país.

Newcastle disease virus-attenuated vaccine LaSota played a key role in the pathogenicity of contaminated exogenous virus

Newcastle disease virus (NDV)-attenuated vaccine has been widely used since the 1950s and made great progress in preventing and controlling Newcastle disease. However, many reports mention exogenous virus contamination in attenuated vaccines, while co-contamination with fowl adenovirus (FAdV) and chicken infectious anaemia virus (CIAV) in the NDV-attenuated vaccine also emerged in China recently, which proved to be an important reason for the outbreaks of inclusion body hepatitis–hydropericardium syndrome in some flocks. It is amazing that exogenous virus contamination at extremely low doses still infected chickens and induced severe disease; thus, we speculated that there must be some interaction between the NDV-attenuated vaccine and the contaminated exogenous viruses within. Accordingly, simulation experiments were launched using FAdV and CIAV isolated from the abovementioned vaccine. The results showed that the pathogenicity of FAdV and CIAV co-infection through the contaminated vaccine was significantly higher than that of direct oral infection, while the synergistic reaction of these viruses and LaSota prompted their multiplication in vivo and disturbed the production of antibodies against each other. This study showed the interactions of FAdV, CIAV and LaSota after using contaminated NDV-attenuated vaccine, helping us to understand how the contaminated exogenous viruses cause infection and induce severe disease at a relatively low dose through the oral route.

Molecular characterization of fowl aviadenoviruses species D and E associated with inclusion body hepatitis in chickens and falcons indicates possible cross-species transmission

ABSTRACTDuring the period from 2015 to 2017, frequent outbreaks of inclusion body hepatitis (IBH) were observed in broiler chickens and falcons in Saudi Arabia. Fifty samples were collected from both species. The histopathological examination and polymerase chain reaction confirmed the IBH infection in eight samples (five samples from chickens and three samples from falcons). The genomic sequence and phylogenetic analysis based on nucleotide and amino acid sequences of Saudi strains, reference fowl aviadenoviruses (FAdVs) and field viruses available in Genbank revealed that all investigated FAdVs clustered into FAdV-2 (species D) and FAdV-6 (species E). The host-dependent characterization revealed that falcon origin strains showed low identity (∼35%) with falcon adenoviruses isolated from USA, which clustered into a separate group. The identification of FAdV-D and FAdV-E in diseased falcons and chickens indicates cross-species transmission although falcons and chickens are phylogenetically different. The control of IBH infection in falcons and chickens should be based on the separation of carriers and susceptible chickens as well as falcons to prevent cross-species contact. Vaccination is an important method for prevention of IBH. The characterization of newly emerging FAdV strains provides valuable information for the development of an efficacious control strategy based on the molecular structure of current circulating FAdV strains in different species of birds.

Inactivated and live bivalent fowl adenovirus (FAdV8b + FAdV11) breeder vaccines provide broad-spectrum protection in chicks against inclusion body hepatitis (IBH)

Fowl adenovirus (FAdV) is comprised of five species (A to E) and 12 serotypes (1–7, 8a, 8b, 9–11). Inclusion body hepatitis (IBH) is caused by FAdV-7, 8a, 8b (species E) and FAdV-2 and 11 (species D). Commercial vaccines against IBH are not available in Canada. Autogenous FAdV broiler breeder vaccines are now used in some areas where outbreaks of IBH are occurring. The objective of this study was to evaluate the efficacy of a bivalent (species D and E) live and an inactivated FAdV broiler breeder vaccine in protecting broiler chicks against IBH through maternal antibody (MtAb) transfer. FAdV seronegative broiler breeders (n = 300/group) received either a live or inactivated bivalent (FAdV-8b-SK + FAdV-11-1047) vaccine. The live vaccine (1 × 104 TCID50 of each virus/bird) was given orally once at 16 weeks of age and the inactivated vaccine (1 × 106TCID50 of each virus + 20% Emulsigen D) was given intramuscularly at 16 and 19 weeks of age. Controls (n = 150) were given saline orally. The inactivated vaccine group was boosted 3 weeks later with the same vaccine. Neutralizing antibodies (NAb) in sera (n = 10) were detected at 19, 22, 30 and 48 weeks of age. NAb were able to neutralize various FAdV serotypes within species D and E. Mean NAb were similar in the both live and killed vaccine groups at 19, 30 and 48 weeks and ranged from 2.4 to 3.7 log10. Approximately 26 ± 7% of MtAbs were passively transferred through eggs to day-old chicks. Progeny challenged with a lethal dose (1 × 107 TCID50/bird intramuscularly) of FAdV-8b-SK, FAdV-11-1047, or FAdV-2-685 (n = 90/group) at 14 days post-hatch (dph) showed 98–100% protection in broiler chicks to homologous or heterologous FAdV challenges. Our data suggests that a bivalent live and an inactivated FAdV vaccine are equally effective and have the potential for the control of IBH.

An unusual outbreak of inclusion body hepatitis on a broiler chicken farm: a case report

This study investigated an outbreak of inclusion body hepatitis in ROSS 308 hybrid broiler type chickens between 19 and 25 days of fattening. For this purpose, clinical observation, ELISA fowl adenovirus and chicken anaemia virus antibody detection in serum at 21 and 42 days, mortality evaluation, epidemiological analysis, histology and genetic identification were performed. The six flocks of the farm consisted of 90,000 chickens. Only one flock of 15,000 chickens was affected on this farm. At 19 days of age, ill chickens showed clinical signs of depression, anorexia, somnolence, ruffled feathers, anaemic comb and wattles and occasionally nervous signs. Based on ELISA titres, the antibody response to fowl adenovirus increased greatly from 21 to 42 days. The antibody response to vaccination against infectious bursal disease virus and chicken anaemia virus was at the expected level in all broiler flocks. Necropsy showed diffuse petechial and ecchymotic haemorrhages in skeletal muscles, liver, pancreas, kidney, together with hepatomegaly, splenomegaly and catarrhal enteritis. Histologically, fatty liver degeneration, multifocal liver necrosis and intranuclear inclusions in hepatocytes, as well as focal necrosis in pancreas and spleen parenchyma were seen. The DNA of AAV-1 (avian adenovirus group 1) was detected using the PCR method in paraffin-embedded liver samples. The results revealed no association of inclusion body hepatitis with infectious bursal disease virus or chicken anaemia virus infection, and suggested primary disease. However, the involvement of only one chicken flock on the farm remains unexplained.

Chronologic Analysis of Gross and Histologic Lesions Induced by Field Strains of FAdV-1, FAdV-8b, and FAdV-11 in Six-Week-Old Chickens.

Inclusion body hepatitis (IBH) is a disease affecting broiler chicken flocks worldwide. Several serotypes of fowl adenovirus (FAdV) have been implicated in disease outbreaks, with and without immunosuppression as a predisposing factor. IBH usually occurs in flocks up to 30 days of age; it is seldom seen in older birds. The objective of this study was to determine whether the pathogenicity for older birds of three FAdV field strains, belonging to serotypes 1, 8b, and 11, in the absence of immunosuppressive factors, was akin to that for younger birds, and to establish an effective and economical disease model for assessing cross-protection between serotypes. To achieve this objective, the gross pathology, histopathology, and dissemination of virus were examined at multiple time points after inoculation of 6-wk-old, specific-pathogen-free chickens via intraperitoneal injection. Both FAdV-8b and FAdV-11 generated lesions typical of those associated with outbreaks of IBH, and they were shown to be primary pathogens. The presence and severity of hepatic lesions were used to define two disease stages: degeneration (1-5 days postinoculation) and convalescence (6-14 days postinoculation). During the degenerative stage, FAdV-8b was detected in the liver, kidney, and gizzard of most birds, whereas FAdV-11 was predominantly detected in the liver, and both viruses persisted in the gizzard into convalescence. The pathogenesis of two IBH-associated FAdV strains in 6-wk-old chickens confirms their high level of virulence and also provides an effective experimental model for investigation of cross-protection between FAdVs. It also demonstrates persistence of the virus in the gizzard long after infection, supporting the notion that it is a site of viral shedding.

Detailed molecular analyses of the hexon loop-1 and fibers of fowl aviadenoviruses reveal new insights into the antigenic relationship and confirm that specific genotypes are involved in field outbreaks of inclusion body hepatitis

Forty-eight fowl aviadenoviruses (FAdVs) isolated from recent IBH outbreaks across Europe were investigated, by utilizing for the first time the two major adenoviral antigenic domains, hexon loop-1 and fiber, for compound molecular characterization of IBH-associated FAdVs.Successful target gene amplification, following virus isolation in cell culture or from FTA-card samples, demonstrated presence of FAdVs in all cases indicative for IBH. Based on hexon loop-1 analysis, 31 European field isolates exhibited highest nucleotide identity (>97.2%) to reference strains FAdV-2 or -11 representing FAdV-D, while 16 and one European isolates shared >96.0% nucleotide identity with FAdV-8a and -8b, or FAdV-7, the prototype strains representing FAdV-E. These results extend recognition of specific FAdV-D and FAdV-E affiliate genotypes as causative agents of IBH to the European continent.In all isolates, species specificity determined by fiber gene analysis correlated with hexon-based typing. A threshold of 72.0% intraspecies nucleotide identity between fibers from investigated prototype and field strains corresponded with demarcation criteria proposed for hexon, suggesting fiber-based analysis as a complementary tool for molecular FAdV typing. A limited number of strains exhibited inconsistencies between hexon and fiber subclustering, indicating potential constraints for single-gene based typing of those FAdVs.Within FAdV-D, field isolate fibers shared a high degree of nucleotide (>96.7%) and aa (>95.8%) identity, while FAdV-E field isolate fibers displayed greater nucleotide divergence of up to 22.6%, resulting in lower aa identities of >81.7%.Furthermore, comparison with FAdVs from IBH outbreaks outside Europe revealed close genetic relationship in the fiber, independent of the strains’ geographic origin.

Pathology of inclusion body hepatitis and hydropericardium syndrome in broiler chicken in natural outbreaks in Odisha

Natural outbreaks of inclusion body hepatitis (IBH) and hydropericardium syndrome (HPS) occurred in various broiler farms of coastal districts of Odisha within a span of 5 months from August to December, 2011. Pathological investigation revealed macroscopic lesion of pale, friable, haemorrhagic and swollen liver. Hydropericardium was seen in most of the cases. Occasionally, the pericardial fluid was coagulated giving cloudy appearance. Kidneys were pale and swollen. Histopathologically, changes like necrotic foci and reticulation in hepatic parenchyma were commonly observed, with presence of fatty changes in most of the instances. Intranuclear inclusions were often detected in hepatocytes that were taken as diagnostic for IBH. The disease occurred alone or in association with infectious bursal disease and colibacillosis.

Molecular differentiation and pathogenicity of Aviadenoviruses isolated during an outbreak of inclusion body hepatitis in South Africa.

Fowl adenovirus (FAdV) is a member of the genus Aviadenovirus and causes a number of economically important poultry diseases. One of these diseases, inclusion body hepatitis (IBH), has a worldwide distribution and is characterised by acute mortality (5% - 20%) in production chickens. The disease was first described in the United States of America in 1963 and has also been reported in Canada, the United Kingdom, Australia, France and Ireland, but until now, not in South Africa. Adenoviruses isolated from the first outbreak of IBH in South Africa were able to reproduce the disease in chicken embryo livers. The aim of the present study was to characterise the viruses and determine the pathogenicity of the FAdV strains responsible for the first reported case of IBH in South Africa. Polymerase chain reaction (PCR) amplification of the L1 loop region of the fowl adenovirus hexon gene using degenerate primer pair hexon A/B was used to identify the viruses that were isolated. Restriction fragment length polymorphism (RFLP) of the amplification products was used for the differentiation of 14 isolates of fowl adenovirus. Sequencing of the PCR products followed by amino acid comparison and phylogenetic analysis using the L1 loop region of the hexon protein was done to determine the identity of the isolates. Amino acid sequences of the hexon genes of all the South African isolates were compared with those of reference strains representing FAdV species. Amino acid comparison of 12 South Africa field isolates to FAdV reference strains revealed a high sequence identity (> 93.33%) with reference strains T8-A and 764. Two of the isolates had high sequence identity (93.40%) with reference strains P7-A, C2B and SR48. Phylogenetic analysis of the L1 loop region of the hexon protein of all 14 South African isolates was consistent with their RFLP clusters. The mortality rates of embryos challenged with 106 egg infective doses (EID50) FAdV 2 were 80% - 87% and mortality rates for embryos challenged with 105.95 (EID50) FAdV 8b were 65% - 80%.

High Incidence of Glomerulonephritis Associated with Inclusion Body Hepatitis in Broiler Chickens: Routine Histopathology and Histomorphometric Studies

During the routine histologic evaluation of an outbreak of inclusion body hepatitis (IBH) in Mississippi broilers, a high incidence of renal enlargement and glomerulonephropathy was observed in the birds presenting classic hepatic pathology. Characteristic intranuclear adenoviral inclusion bodies were demonstrated in the livers of these birds, and fowl adenovirus was identified by viral isolation and by PCR. The glomerular lesions were consistent with proliferative or membranoproliferative forms of glomerulonephritis. Histomorphometric evaluations were performed to generate a more quantitative analysis of altered glomerular size and cellularity, to detect statistically significant borderline changes, and to get a clearer insight into the incidence of the glomerular alterations. Marked increases in both the average glomerular size (area) and the total glomerular cellularity were observed for the affected glomeruli relative to normal controls. The average glomerular area values for normal glomeruli in the peripheral subcapsular cortical and central cortical kidney regions were 1791 microm2 and 5302 microm2, respectively. In contrast, glomerular measurements for kidneys exhibiting glomerulonephritis by routine histopathology, had average values for the two regions of 4429 microm2 and 11,063 microm2. The average glomerular cell counts for the two regions in controls were 44 and 107 cells/ glomeruli, while averages for birds with glomerulonephritis were 85 and 193 cells/glomeruli. The proportion of IBH-associated glomeruli greater than two standard deviations above the mean glomerular size of the normal controls was 52% for the central region and 62% for the peripheral region.