Inclusion Body Hepatitis-hydropericardium Syndrome Research Articles

Síndrome da hepatite-hidropericárdio por Aviadenovirus e em reprodutores de corte

ABSTRACT: Fowl aviadenovirus (FAdV) is an important pathogen in the global poultry industry and the etiology of inclusion body hepatitis-hydropericardium syndrome (HHS) in chickens. Since the 1990s, several outbreaks of HHS have occurred in poultry producing areas, including South America. The coinfection of FAdV and chicken anemia virus (CAV) may markedly impact the incidence of HHS. This study describes an outbreak of HHS in coinfection with CAV in industrial broiler breeders and characterizes the FAdV isolate. The three-week-old male broiler breeders had pale bone marrow, enlarged and yellowish liver, splenomegaly, and atrophied thymus; one chicken was also found with hydropericardium. Virus isolation was performed in SPF chicken embryos of liver and thymus. Tissues of the naturally infected chickens and the inoculated embryos were evaluated by PCR and histopathology. All affected chickens and inoculated embryos were positive for FAdV and CAV. The inoculated embryos had enlarged, greenish and hemorrhagic livers, and 30% died within 7 days of inoculation. Phylogenetic analysis of the FAdV isolate hexon gene partial sequence enabled grouping with E species. The E species has recently become a relevant species in several countries. The association of FAdV with CAV in breeders is of further concern due to both being capable of vertical transmission. Within the last decade, a worldwide upsurge of HHS in broiler breeders owing to failed biosecurity has occurred. In this episode, the failure on biosecurity may have enabled challenge with both FAdV and CAV, with pathological synergism. The CAV-impaired adaptive immunity may have benefited the FAdV infection.

Pathogenicity Assessment and Vaccine Efficacy of Fowl Adenovirus Serotype 4 and 11 Responsible for Inclusion Body Hepatitis Hydropericardium Syndrome in Broilers

Thisstudy aimed to assess the pathogenicity and vaccine efficacy of fowl adenovirus serotypes 4 and 11, causing inclusion body hepatitis hydropericardium syndrome in broilers. The study was carried out on 144-day-old Cobb broiler chicks divided into six experimental groups, each of 24 birds. Group, I birds served as a control without any vaccine or viral challenge, while birds of Group II were vaccinated with commercial vaccine on 6th day. Group III and IV birds were non-vaccinated and challenged with 107 TCID50 of FAdV serotype 4 and 11, respectively, on the 27th day. In contrast, Group V and VI birds were vaccinated on the 6th day and challenged with 107 TCID50 of FAdV serotype 4 and 11 on the 27th day. The challenge of FAdV serotype 4 led to 66.66% mortality, and serotype 11 produced 5.00% mortality in the experimental groups. The challenge of the virus led to the production of clinical signs such as depression, huddling, reduced feed intake, reluctance to move, and terminal gasping before death. Characteristic gross lesions of IBH-HPS were observed in birds that died after the challenge of serotypes 4 and 11 of FAdV. The liver was enlarged with focal areas of necrosis, subcapsular hemorrhages, and mild fatty changes. The heart was flabby, congested, and showed hydropericardium with an accumulation of clear watery to a yellow jelly-like fluid in the pericardial sac. The kidneys were enlarged and hemorrhagic. On microscopic examination, the liver showed multifocal areas of necrosis with infiltration of mononuclear cells, mild fatty changes and large basophilic intranuclear inclusion bodies. The birds that died after the challenge of the virus were positive for the presence of FAdV upon PCR. The vaccine efficacy study indicated that the vaccine provided satisfactory protection against Fowl Adenovirus challenge in experimental groups V and VI.

Isolation and Molecular Characterization of Fowl Adenoviruses Associated with Inclusion Body Hepatitis-hydropericardium Syndrome in Broiler Chickens in Egypt

Avian adenoviruses are an extremely diversified group of pathogens that recently triggering a variety of problems for poultry production. In particular, Inclusion Body Hepatitis-Hydropericardium Syndrome (IBH-HPS), which has been observed in broiler birds from 3 to 6 weeks of age and is associated with anemia, hemorrhagic disorders, hydropericardium, and high mortality. The disease has been reported worldwide, and recently it was reported in many Egyptian farms, causing severe economic losses. Therefore, the current study aimed to isolate, and genetically type the most common Adenovirus serotypes associated with this syndrome in Egyptian farms. A total of 50 broiler chicken farms (3-6 weeks old) located in different Egyptian governorates were examined. Macroscopically, the diseased flock revealed hydropericardium, enlarged friable livers with ecchymotic hemorrhages, and varying mortality rates (1 to 7.5%). Histopathologically, severe diffuse necrotizing enteritis, hepatitis, pericarditis, and diffuse lymphoid depletion of the spleen were the most prominent lesions. Liver tissues and cloacal swabs were collected from all examined flocks for FAdVs detection by conventional polymerase chain reaction (PCR) targeting the L1 loop in the hexon gene. The PCR products were sequenced for typing of the detected viruses. It was found that 10 out of 50 flocks examined were PCR positive for FAdVs (20%). Phylogenetic analysis of the sequenced genes revealed that the obtained viruses clustered with reference strains belonging to FAdV type D and E serotype 2, 11, and 8a respectively. The isolation of both FAdV type D and FAdV type E were carried out on a primary cell culture chicken embryo liver cell (CEL) and the presence of these viruses was confirmed by PCR after the appearance of cytopathic effect (CPE). From this study, it could be concluded that both FAdVs types D and E are the most common adenoviruses circulating in poultry farms suffering from hydropericardium and inclusion body hepatitis.

Chicken infectious anemia virus helps fowl adenovirus break the protection of maternal antibody and cause inclusion body hepatitis-hydropericardium syndrome in layers after using co-contaminated Newcastle disease virus-attenuated vaccine.

Inclusion body hepatitis-hydropericardium syndrome (IBH-HPS) caused by fowl adenovirus type 4 (FAdV-4) has caused huge economic losses for China in the past five years. At present, this disease is controlled in many flocks with the inactivated FAdV vaccine, but the offspring chicks of a layer breeding flock that were vaccinated with this vaccine still became infected and developed IBH-HPS with a 20% mortality rate. Analysis revealed that the NDV-attenuated vaccine in use from the above-mentioned poultry farm was simultaneously contaminated with FAdV-4 and chicken infectious anemia virus (CIAV). The FAdV and CIAV isolated from the vaccine were purified for the artificial preparation of an NDV-attenuated vaccine singly contaminated with FAdV or CIAV, or simultaneously contaminated with both of them. Seven-day-old layers with maternal FAdV antibody were inoculated with the artificially prepared, contaminated vaccines and assessed for corresponding indices. The experiments showed that no obvious symptoms occurred after using the NDV-attenuated vaccine singly contaminated with FAdV or CIAV; however, common IBH and occasional HPS-related death was found in birds after administering the NDV-attenuated vaccine co-contaminated with FAdV and CIAV. In conclusion, this study illustrated that CIAV could assist FAdV in breaking maternal FAdV antibody protection, which then caused the IBH-HPS after vaccination with the co-contaminated NDV vaccine.

The intracorporal interaction of fowl adenovirus type 4 and LaSota strain significantly aggravates the pathogenicity of one another after using contaminated Newcastle disease virus-attenuated vaccine.

In the past five years, inclusion body hepatitis-hydropericardium syndrome caused by fowl adenovirus type 4 (FAdV-4) has been rampant in China and is still an epidemic at present. We had found the contamination of FAdV-4 in Newcastle disease virus (NDV)-attenuated vaccine from a large farm with aforementioned disease, and then conjectured that the use of this contaminated vaccine might be an important reason for the outbreak of the FAdV-4 infection. To assess the pathogenicity of this contaminated vaccine and the interaction between FAdV and LaSota, systemic animal experiments were launched with FAdV infection via the contaminated vaccine, as well as FAdV direct infection. Results showed that no chicks died after FAdV direct infection, while a 16.7% mortality rate appeared after FAdV infection through the contaminated vaccine; the synergistic reaction of FAdV and LaSota aggravated their inhibitory action for weight growth of SPF chickens, enhanced one another's capacity for immune system destruction, promoted their multiplication in vivo, and restrained antibody production. This study demonstrated the intracorporal interaction and enhanced pathogenicity of FAdV-4 and LaSota strain in contaminated NDV-attenuated vaccine, illustrating how the exogenous virus causes infection and induces severe diseases, which reminds us that the damage of attenuated vaccine contaminated with FAdV-4 even in extremely low dose is not insignificant.

Newcastle disease virus-attenuated vaccine co-contaminated with fowl adenovirus and chicken infectious anemia virus results in inclusion body hepatitis-hydropericardium syndrome in poultry

Inclusion body hepatitis-hydropericardium syndrome (IBH-HPS) induced by fowl adenovirus type 4 (FAdV-4) has caused huge economic losses to the poultry industry of China, but the source of infection for different flocks, especially flocks with high biological safety conditions, has remained unclear. This study tested the pathogenicity of Newcastle disease virus (NDV)-attenuated vaccine from a large-scale poultry farm in China where IBH-HPS had appeared with high mortality. Analysis revealed that the NDV-attenuated vaccine in use from the abovementioned poultry farm was simultaneously contaminated with FAdV-4 and chicken infectious anemia virus (CIAV). The FAdV and CIAV isolated from the vaccine were purified for the artificial preparation of an NDV-attenuated vaccine singly contaminated with FAdV or CIAV, or simultaneously contaminated with both of them. Seven-day-old specific pathogen-free chicks were inoculated with the artificially prepared contaminated vaccines and tested for corresponding indices. The experiments showed that no hydropericardium syndrome (HPS) and corresponding death occurred after administering the NDV-attenuated vaccine singly contaminated with FAdV or CIAV, but a mortality of 75% with IBH-HPS was commonly found in birds after administering the NDV-attenuated vaccine co-contaminated with FAdV and CIAV. In conclusion, this study found the co-contamination of FAdV-4 and CIAV in the same attenuated vaccine and confirmed that such a contaminated attenuated vaccine was a significant source of infection for outbreaks of IBH-HPS in some flocks.

Overexpression and characterization of the 100K protein of Fowl adenovirus-4 as an antiviral target

100K is an important scaffolding protein of adenoviruses including fowl adenovirus serotype 4 (FAdV-4) that causes inclusion body hepatitis-hydropericardium syndrome (IBH-HPS) in poultry. 100K carries out the trimerization of the major capsid hexon protein of the virus for the generation of new virions inside the target host cells. Despite its critical role for FAdV-4, no structural study, in particular, has been conducted so far. Here, the overexpression of soluble 100K protein was successfully carried out in E. coli using various expression constructs and purification yield of 3mg per litre culture volume was obtained. Gel filtration chromatography suggested that 100K protein exists in trimeric form. Circular dichroism and Fourier transform infrared spectroscopy clearly reveal that 100K protein folds with a high content of α-helices. The 3-dimentional homology model of the 100K protein, refined with molecular dynamics tools also depicts higher α-helical content within the protein model. Moreover, overexpressed recombinant 100K protein could be used to differentiate vaccinated and FAdV-4 infected chickens on the basis of higher serum anti 100K antibody titres. Our work provides preliminary structural and functional results to study biological role of the 100K protein and for further investigations to develop 100K inhibitors to control IBH-HPS in poultry.

English

English

Immune system dysfunction in broiler chickens experimentally inoculated with fowl adenovirus serotype-4 associated with inclusion body hepatitis hydropericardium syndrome

Inclusion body hepatitis-hydropericardium syndrome (IBH-HPS) in broilers is caused by an adenovirus, here referred to as inclusion body hepatitis-hydropericardium syndrome virus (IBH-HPSV). This study describes the immune status of broiler chickens experimentally inoculated with an isolate of fowl adenovirus-4 serotype-1, involved in IBH-HPS in various trials. When compared with the unchallenged controls, IBH-HPSV-inoculated broilers had significantly higher atrophy of the bursa of Fabricius (BF) by up to 2-fold, as well as of the thymus (up to 9-fold) and spleen (up to 1.5-fold) (P < 0.05), with up to 60% mortality. Upon challenge with sheep red blood cells (SRBCs), IBH-HPSV-inoculated birds had from 2- to 3-log lower anti-SRBC antibody titers than the control. Response to phytohemagglutinin-P (PHA-P) was significantly reduced in IBH-HPSV-inoculated birds (P < 0.05) as compared to the control. Results of the studies revealed that the immune status of broilers is compromised significantly during IBH-HPSV infection in terms of lymphoid organ integrity, humoral, and cell-mediated immune responses, respectively. These findings suggest that immune dysfunction could be a contributing factor in the increased mortality of birds affected by IBH-HPS, which renders the birds immunosuppressed for the rest of their lives.

Molecular charecterization of Avian Adeno virus causing Inclusion Body Hepatitis-Hydropericardium syndrome in broiler chickens of Anand, Gujarat, India

Molecular charecterization of Avian Adeno virus causing Inclusion Body Hepatitis-Hydropericardium syndrome in broiler chickens of Anand, Gujarat, India

닭 유래 아데노 바이러스 혈청형 4형(FAdV-4) 사독 오일 백신의 안전성 및 효능 평가

봉입체성 간염-심낭수종증(IBH-HPS)은 주로 육계에서 다발하며 3~6주령의 육계에서 최고 75%까지의 폐사율을 일으킬 수 있는 질병이다. 주 증상으로는 심낭의 황색 수양성 액체가 저류되는 심낭수종증과 함께 봉입체성 간염이 나타난다. 1987년 파키스탄에서 처음 발생이 보고된 후 여러 나라에서 발병되었으며, 최근 우리나라에서도 질병 발생이 확인된 바 있다. 본 실험에서는 IBH-HPS에 대한 경제적 피해를 감소시키기 위한 목적으로 사독 오일 백신을 제조하여 안전성 및 효능을 평가하였다. 2주령의 SPF 닭에 제조한 사독 백신을 1 또는 2수분으로 근육 접종한 뒤 2주 후인 4주령에 FAdV-4로 공격 접종을 실시하였다. 백신 접종에 의한 임상 증상 발현 및 폐사가 관찰되지 않아 백신의 안전성이 인정되었고, AGP 검사를 통해 FAdV-4에 대한 항체가 100% 형성되었음을 확인하였다. 공격 접종 시 각각 경구 또는 근육으로 접종하였고, 접종 후 10일간 관찰한 결과, 백신 접종군 모두 부검 소견, 바이러스 유전자 검색율 및 조직학적 병변도에 있어서 효능이 인정되었다. 육안 병변의 경우, 백신 비접종군에서는 간의 괴사 반점이 10~50%의 개체에서 발생한 데 비해 백신 접종군에서는 관찰되지 않았다. 바이러스 유전자 검색 양성률 또한 백신 접종군이 백신 비접종군에 비해 낮은 수준으로 나타났으며, 이는 특히 근육 투여군에서 더 명확하게 나타났다. 조직 병변도는 관찰 기간 내내 핵내 봉입체는 관찰되지 않았으나, 림프구 침윤 및 간세포의 괴사 정도가 백신 접종군에서 현저히 감소한 것을 확인할 수 있었다. 따라서, 본 실험에서 제조한 FAdV-4 사독 오일 백신은 실험계에 임상적으로 안전하고 면역원성도 높았으며, 효능에 있어서는 백신 비접종군에서의 임상 증상이 명확하지 않았음에도 불구하고, 육안 병변, 바이러스 검색율 및 조직 병변도에 있어서 공격 접종에 대한 방어가 효과적인 것으로 판단된다. Inclusion body hepatitis-hydropericardium syndrome (IBH-HPS) is an acute viral disease usually found in broilers aged from 3 to 5 weeks and causes up to 75% mortality. Among the 12 serotypes of fowl adenovirus group 1, serotype-4 (FAdV-4) was identified as a primary agent of IBH-HPS and was usually isolated in IBH-HPS cases in Korea since 2007. To prevent these IBH-HPS outbreaks in Korea, we developed the FAdV-4 inactivated vaccine using Korean isolate (ADL070244) and evaluated the efficacy of this vaccine. For the efficacy test, 2-week-old specific-pathogen-free (SPF) chickens intramuscularly inoculated with 1 or 2 dose of inactivated vaccine were used and challenged with FAdV-4 through either intramuscular or oral route at 2 weeks after vaccination. The vaccine induced good seroconversion which was confirmed by agar gel precipitation (AGP) test. In addition, the vaccine could decrease the FAdV-4 detection rate and histological lesion severity such as lymphocyte infiltration and necrosis in the liver comparing with those of non-vaccination group. Based on the current results, the developed FAdV-4 inactivated vaccine in this study was effective in the terms of reduction of virus detection rate and histological lesions severity. However, it was difficult to confirm the efficacy of the vaccine clearly because of no mortality and clinical signs in the non-vaccinated group after challenge. Therefore, we need further study to develop a standard challenged model system which could clearly evaluate the efficacy of the vaccines for FAdV-4.

The hydropericardium syndrome in poultry--a current scenario.

Inclusion-body hepatitis hydropericardium syndrome (IBH-HPS) is an important, recently emerged, disease of poultry, particularly of 3- to 6-week-old broiler chicks, characterized by its sudden onset, with high mortality ranging from 20% to 70%, typical hydropericardium and enlarged mottled and friable livers, with intranuclear inclusion bodies in the hepatocytes. The causative agent is a non-enveloped icosahedral fowl adenovirus (FAV) serotype 4, belonging to the Adenovirus genus of the family Adenoviridae, which can be propagated or cultivated in chicken embryo liver and kidney primary cell cultures. The transmission of disease occurs vertically and laterally by the oral-faecal route. The liver of infected birds shows necrotic foci and basophilic intranuclear inclusion bodies in the hepatocytes. The disease can be diagnosed from its gross and histopathological changes in the liver and by various serological tests, such as agar gel immunodiffusion, counterimmunoelectrophoresis, indirect haemagglutination, the fluorescent antibody technique, enzyme-linked immunosorbent assay and the polymerase chain reaction. The disease has been brought under control by the use of formalin-inactivated vaccines, prepared from infected liver homogenate, and of inactivated cell culture vaccines. The vaccines are effective in the face of natural outbreaks or experimental challenge and significantly reduce the mortality.

Antigenic Characteristics of Fowl Adenovirus-4 (FAV-4) Isolates from Inclusion Body Hepatitis-hydropericardium Syndrome of Chickens

Kaur, G., Maiti, N.K. and Oberoi, M.S. 2002. Antigenic characteristics of fowl adenovirus-4 (FAV-4) isolates from inclusion body hepatitis-hydropericardium syndrome of chickens. J. Appl. Anim. Res., 22: 231–236. Two-dimensional (crossed) immunoelctrophoresis of 10 FAV-4 isolates revealed 6 immunoprecipitate peaks with FAV-4 antiserum. Purified isolates and standard FAV-4 strain revealed 8 structural polypeptides in SDS-PAGE ranging between 18 to 116 KD in molecular weight. Out of the eight polypeptides, only six polypeptides between 35–166 KD molecular weight were found to be immunogenic in immunoblotting study. This indicated no antigenic differences in the FAV-4 isolates from IBH-HPS cases.