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Infectious bursal disease (IBD) affects young chicks, inducing immune suppression, intestinal dysbiosis, poor growth performance, and mortalities. Our aim is to study the role of prebiotics and probiotics in overcoming dysbiosis related to IBD experimental infection. One-day-old chicks were divided into six groups (n=18) as four groups were given Enterococcus faecium (T1), Saccharomyces cerevisiae (T2), organic acids (T3), and symbiotic (T4) for five days at the 3rd-day post-infection. Groups 5 and 6 were considered negative control (NC) and positive control (PC). At 14 days old, all groups were challenged via eye drops with very virulent IBDV strain (MK088026), except the NC group. Feed conversion ratio (FCR), histopathological changes, and gut microbiome profile using 16srRNA gene sequencing were studied. Severe depletion of the bursa was observed in the PC group but was less severe in treated infected groups. 8 dpi, a significant decrease in cecum villous length (p<0.05) was observed in the PC group compared to the NC group, while it was corrected in treated infected groups. Cecal microbiome profile was studied on the 3rd and 8th-day post-infection (dpi). The IBD virus caused a decrease in the family Lachnospiraceae and family Ruminococcaceae compared to the NC group. In contrast, the treated infected groups showed an increase in the relative abundance of phylum Bacteroidetes, family Ruminococcaceae, and family Lachnospiraceae than the PC group. IBD infection caused poorer FCR than the NC group. In contrast, treated infected groups showed higher improvement in FCR than the PC group. [ABSTRACT FROM AUTHOR]

Gumboro disease is a viral poultry disease that causes immune suppression on the infected birds leading to poor production, mortality, and exposure to secondary infections, hence a major threat in the poultry industry worldwide. A mathematical model of the transmission dynamics of Gumboro disease is developed in this paper having four compartments of chicken population and one compartment of Gumboro pathogen population. The basic reproduction number R og is derived, and the dynamical behaviors of both the disease-free equilibrium (DFE) and endemic equilibrium are analyzed using the ordinary differential equation theory. From the analysis, we found that the system exhibits an asymptotic stable DFE whenever R og < 1 and an asymptotic stable EE whenever R og > 1. The numerical simulation to verify the theoretical results was carried out using MATLAB ode45 solver, and the results were found to be consistent with the theoretical findings. [ABSTRACT FROM AUTHOR]

In Egypt, the poultry industry is plagued by the significant economic losses caused by the infectious bursal disease virus (IBDV). In the present study, a total of 30 diseased commercial chicken flocks aged 23-41 days old in three Egyptian governorates (Fayoum, Beni-Suef, and Minya) having symptoms consistent with IBDV were examined. The collected bursal samples (n=30, ten pooled bursae for each flock) were screened by RT-PCR to amplify the IBDV VP2 gene. Results revealed that 20 out of 30 samples were positive, as indicated by the amplification of 620 bp of the VP2 gene. The twenty positive samples were inoculated into specific pathogen-free embryonated chicken eggs (SPF-ECEs) via the chorioallantoic-membrane (CAM) route to isolate the suspected virus. Eight samples were successfully isolated and were subjected to a partial sequence of VP2 (targeting the HVR). The nucleotide sequences and phylogenetic analysis revealed that the examined isolates exhibited amino acids A222, I256, I294, and S299, which are extremely conserved among very virulent (vv)IBDV. The amino acid sequence analysis of the eight isolates revealed a high degree of similarity (97-100%) in between and 90-100% similarity compared to other Egyptian vvIBDV strains. In contrast, lower similarity was observed with attenuated IBDV vaccine strains D78, Lukert, and Bursavac (91-93%, 91-93%, and 92-94%, respectively). In conclusion, this study underscores the importance of ongoing surveillance of the IBDV situation in the field, as well as the need for further research to investigate the efficacy of current vaccination strategies to curb IBDV infection. [ABSTRACT FROM AUTHOR]

Infectious Bursal Disease (IBD) or Gumboro is caused by the IBD virus of the Birnaviridae family. The disease is acute and highly contagious in young birds. The virus infection causes severe damage to the lymphoid organs i.e. bursa Fabricius leading to immunosuppression. The disease morbidity may reach 100%, while the mortality varies from 20 to 100%, causing high economic losses. Infectious Bursal Disease has remained significant threat although vaccination has been applied. This study aimed to determine the current typical pathological changes in the bursa Fabricius of commercial broilers showing IBD symptoms. The samples were obtained from commercial broiler farms in Sragen, Wonogiri, Batang, and Sleman. Gross lesion examination showed enlargement of the bursa Fabricius with gelatinous material on the serosal surface, oedema with fluid accumulation in the lumen, hemorrhages of the serosal surface, atrophy, and caseous exudate in the lumen. Histopathologic changes of acute IBD include hemorrhages, congestion, lymphocyte necrosis, accumulation of fibrin, oedematous and heterophils infiltration in the interfollicular tissues. Microscopic changes in chronic IBD (5-7 days post infection IBDV) including follicular atrophy, lymphocyte necrosis, vacuolization of the follicle, and proliferation of fibroblast and connective tissue in the interfollicular space. In conclusion, the notable pathological change description of bursa Fabricius in suspected acute is gross lesion (swelling and edema, thickened and enlarged plica bursa Fabricius, hemorraghe), microscopic lesion (congestion, hemorraghe, heterophil infiltration) or chronically IBD infection in broiler chicken was gross lesion (atrophy bursa Fabricius, atrophy and excudate casouse in the lumen bursa Fabricius), microscopic lesion (lymphocyte necrosis, vacuolization of bursa Fabricius follicles, proliferation of fibroblasts and interfollicular connective tissue).

Abstract Infectious bursal disease (IBD) is an avian viral disease caused in chickens by infectious bursal disease virus (IBDV). IBDV strains (Avibirnavirus genus, Birnaviridae family) exhibit different pathotypes, for which no molecular marker is available yet. The different pathotypes, ranging from sub-clinical to inducing immunosuppression and high mortality, are currently determined through a 10-day-long animal experiment designed to compare mortality and clinical score of the uncharacterized strain with references strains. Limits of this protocol lie within standardization and the extensive use of animal experimentation. The aim of this study was to establish a predictive model of viral pathotype based on a minimum number of early parameters measured during infection, allowing faster pathotyping of IBDV strains with improved ethics. We thus measured, at 2 and 4 days post-infection (dpi), the blood concentrations of various immune and coagulation related cells, the uricemia and the infectious viral load in the bursa of Fabricius of chicken infected under standardized conditions with a panel of viruses encompassing the different pathotypes of IBDV. Machine learning algorithms allowed establishing a predictive model of the pathotype based on early changes of the blood cell formula, whose accuracy reached 84.1%. Its accuracy to predict the attenuated and strictly immunosuppressive pathotypes was above 90%. The key parameters for this model were the blood concentrations of B cells, T cells, monocytes, granulocytes, thrombocytes and erythrocytes of infected chickens at 4 dpi. This predictive model could be a second option to traditional IBDV pathotyping that is faster, and more ethical.

ABSTRACT: Gumboro virus is one of the most dangerous immunosuppressant viruses that infect chickens and causes massive financial losses worldwide. The current study aims to conduct a molecular characterization of chicken farms for the infectious bursal disease virus (IBDV). Based on postmortem (PM) lesions, 125 bursal samples from 25 farms were collected from clinically diseased commercial chicken farms with increased mortality and suspected Gumboro virus infection. Pooled bursal samples from suspected IBD-vaccinated flocks were tested for IBDV by reverse transcriptase polymerase chain reaction (RT-PCR). Fifteen out of 25 pooled specimens were found positive for IBDV, with a 60% detection rate, and confirmed positive for very virulent IBDV (vvIBDV) by sequence analysis. Nucleotide phylogenetic analysis of VP1 and VP2 genes was employed to compare the 5 chosen isolates with strains representing different governorates in Egypt during 2022. All strains were clustered with vvIBDV with no evidence of reassortment in the VP1 gene. The VP1 and VP2 genes are divided into groups (I, II). The strains in our study were related to group II, and it acquired a new mutation in the VP2 gene that clustered it into new subgroup B. By mutation analysis, the VP2 gene of all strains had a characteristic mutation to vvIBDV. It acquired new mutations in HVRs compared with HK46 in Y220F, A222T/V in all strains in our study, and Q221K that was found in IBD-EGY-AH5 and AH2 in the loop PBC in addition to G254S in all strains in our study and Q249k that found in IBD-EGY-AH1 and AH3 in the loop PDE. These mutations are important in the virulency and antigenicity of the virus. The VP1 had 242E, 390M, and 393D which were characteristic of vvIBDV and KpnI restriction enzyme (777GGTAC/C782) in addition to a new mutation (F243Y and N383H) in IBD-EGY-AH1 and AH4 strains. According to the current study, the strains were distinct from the vaccinal strain; they could be responsible for the most recent IBDV outbreaks observed in flocks instead of received vaccinations. The current study highlighted the importance of molecular monitoring to keep up to date on the circulating IBDV for regular evaluation of commercial vaccination programs against circulating field viruses.

Infectious bursal disease (IBD) is an avian viral disease caused in chickens by infectious bursal disease virus (IBDV). IBDV strains (Avibirnavirus genus, Birnaviridae family) exhibit different pathotypes, for which no molecular marker is available yet. The different pathotypes, ranging from sub-clinical to inducing immunosuppression and high mortality, are currently determined through a 10-day-long animal experiment designed to compare mortality and clinical score of the uncharacterized strain with references strains. Limits of this protocol lie within standardization and the extensive use of animal experimentation. The aim of this study was to establish a predictive model of viral pathotype based on a minimum number of early parameters measured during infection, allowing faster pathotyping of IBDV strains with improved ethics. We thus measured, at 2 and 4 days post-infection (dpi), the blood concentrations of various immune and coagulation related cells, the uricemia and the infectious viral load in the bursa of Fabricius of chicken infected under standardized conditions with a panel of viruses encompassing the different pathotypes of IBDV. Machine learning algorithms allowed establishing a predictive model of the pathotype based on early changes of the blood cell formula, whose accuracy reached 84.1%. Its accuracy to predict the attenuated and strictly immunosuppressive pathotypes was above 90%. The key parameters for this model were the blood concentrations of B cells, T cells, monocytes, granulocytes, thrombocytes and erythrocytes of infected chickens at 4 dpi. This predictive model could be a second option to traditional IBDV pathotyping that is faster, and more ethical. [ABSTRACT FROM AUTHOR]

Infectious bursitis virus (IBDV) is the infectious agent of bursal disease, which mainly affects young poultry populations, generating a negative economic impact on productions. The viral protein 1 (VP1) is an enzyme with important functions for the replication of the viral genome, so it could be considered as a target for searching compounds with possible inhibitory activities. The aim of this research was to evaluate terpenoids with inhibitory potential of the VP1 protein of IBDV using computational approximations tools. A total of 52 terpenoids were selected and evaluated for their pharmacological, pharmacokinetic and toxic properties (ADME-Tox). Molecules without toxic activities and with pharmacokinetic competences were subjected to extensive molecular docking tests with the catalytic site of VP1 using the genetic and Broyden-Fletcher-Goldfarb- Shanno algorithms with a local gradient optimization method. Data obtained revealed that Gibberellin A1 exhibits significantly (P < 0.05) favorable binding free energy values (AG=-7.28±0.06 kcal/mol; Kdcalc 8.62±0.99 pM) compared to rCTP and rGTP substrates. The Gibberellin A1-VP1 complex exhibits hydrogen bonds with residues Arg335 and Asp402, which play important roles in catalytic activity in viral replication. These findings suggest that the terpenoid Gibberellin A1 could be considered as a candidate compound for in vitro studies of inhibition of VP1 functions and in vivo antiviral activities against infectious bursitis virus. [ABSTRACT FROM AUTHOR]

MB-1 is an attenuated infectious bursal disease virus vaccine. Previously, we observed a temporal delay of vaccine virus replication in the bursae of chicks due to maternally derived antibodies (MDAs). The mechanism that allowed its survival despite MDA neutralization remained unclear. We hypothesized that after vaccination at 1 day of age (DOA), the MB-1 virus penetrates and resides in local macrophages that are then distributed to lymphoid organs. Furthermore, MB-1's ability to survive within macrophages ensures its survival during effective MDA protection. PCR analysis of lymphoid organs from chicks with MDA, vaccinated on 1 DOA, demonstrated that the MB-1 virus was identified at low levels solely in the spleen pre-14 days of age. Fourteen days after vaccination, the virus was identified using PCR in the bursa, with viral levels increasing with time. The possible delay in viral colonization of the bursa was attributed to the presence of anti-IBDV capsid VP2 maternal IgA and IgY in the bursa interstitium. These indicate that during the period of high MDA levels, a small but viable MB-1 viral reservoir was maintained in the spleen, which might have served to colonize the bursa after MDA levels declined. Thereafter, individual immunization of chicks against Gumboro disease was achieved. [ABSTRACT FROM AUTHOR]

The present study was aimed to administering hyperimmunized avian salmonella-immune lymphokines (S-ILK) to 200 one-day-old layer pullets to improve the immunological response against Gumboro (IBDV) divided into four groups. On the first day, the following was applied to all groups: G1: intraperitoneal injection of 0.50 mL S-ILK followed by a 30-minute challenge with 0.1 mL IBDV (ELD50 103.2); G2: intraperitoneal injection of 0.5 mL of S-NILK followed by a 30-minute challenge by 0.1 mL IBDV. G3: challenged with 0.1 mL of IBDV only, G4: uninfected, unchallenged group consider as a negative control. The results of the findings indicated the greatest a statistically significant rise (p≤ 0.05) in IgG and IFN-γ titres in that group and the viral load test revealed that at 7 and 14 days after infection, The largest number of IBDV RNA copies were found in G2 and G3. in the bursa of Fabricius. The first group had the lowest mortality rate compared to the other groups. Early S-ILK administration improves maternal resistance to IBDV infection and inhibits viral replication in the fabricius bursa following IBDV challenge. Thus, we may reduce the amount of time, effort, and money spent on immunization procedures that do not completely protect against diseases. [ABSTRACT FROM AUTHOR]

The present explorative study was done to find out the current technological adoption and problems of broiler entrepreneurs including disease prevalence among the farms. Information was gathered by visiting selected chicken farms and interviewing the owners using a prepared questionnaire. The study found several bacterial diseases among the broilers including chronic respiratory disease, Escherichia coli infection, Omphalitis, and viral diseases such as Gumboro (Infectious bursal disease-IBD). The study also found cases of Coccidiosis and mortality from unknown etiology. The study found 14.09 per cent mortality in broiler farms in all the seasons combined. The present study found 4.32, 4.76, and 5.10 per cent mortality in winter, summer, and rainy seasons respectively. The study clearly highlighted the presence of almost all important diseases in broiler birds causing economic loss to farmers and ultimately to the country. The present study conclusively indicates the need to implement biosecurity measures, not just for farmers, but also for veterinarians, public health practitioners, and other stakeholders involved directly or indirectly in poultry production in India. [ABSTRACT FROM AUTHOR]

Nghiên cứu nhằm đánh giá đáp ứng miễn dịch của hai loại vaccine nhược độc chủng M.B. Một trăm ba mươi lăm gà Ác 1 ngày tuổi được bố trí hoàn toàn ngẫu nhiên một yếu tố vào 2 lô gồm (1) tiêm vaccine MB-1 lúc 1 ngày ở trạm ấp và (2) chủng vaccine MB live lúc 7 và 15 ngày ở trại. Gà được lấy máu lúc 1, 14, 21, 24, 28 ngày để kiểm tra hiệu giá kháng thể (HGKT) IBD. Các chỉ số túi Bursa (BI), khối lượng bình quân (KLBQ) và tăng trọng hàng ngày (TTHN) của gà từ 1 đến 49 ngày cũng được theo dõi. Gà con có HGKT mẹ truyền kháng virus IBD là 1515 titer với CV 58,7%. Vào thời gian 14, 21, 24 ngày, HGKT IBD giữa hai lô không có khác biệt về mặt thống kê (P > 0,05). Đến 28 ngày, HGKT IBD của lô MB-1 cao hơn có ý nghĩa so với HGKT lô MB live, 6218 titer so với 5075 titer (P < 0,05). Các thông số BI, KLBQ, TTHN của lô MB-1 có xu hướng cao hơn so với lô MB live qua các thời điểm.

MB-1 is an attenuated infectious bursal disease virus vaccine. Previously, we observed a temporal delay of vaccine virus replication in the bursae of chicks due to maternally derived antibodies (MDAs). The mechanism that allowed its survival despite MDA neutralization remained unclear. We hypothesized that after vaccination at 1 day of age (DOA), the MB-1 virus penetrates and resides in local macrophages that are then distributed to lymphoid organs. Furthermore, MB-1’s ability to survive within macrophages ensures its survival during effective MDA protection. PCR analysis of lymphoid organs from chicks with MDA, vaccinated on 1 DOA, demonstrated that the MB-1 virus was identified at low levels solely in the spleen pre-14 days of age. Fourteen days after vaccination, the virus was identified using PCR in the bursa, with viral levels increasing with time. The possible delay in viral colonization of the bursa was attributed to the presence of anti-IBDV capsid VP2 maternal IgA and IgY in the bursa interstitium. These indicate that during the period of high MDA levels, a small but viable MB-1 viral reservoir was maintained in the spleen, which might have served to colonize the bursa after MDA levels declined. Thereafter, individual immunization of chicks against Gumboro disease was achieved.

In Egypt, several highly pathogenic infectious bursal disease isolates were reported to break through high levels of maternal immunity in commercial flocks. This study investigated viral tropism and immune profiling of circulating very virulent strains in broiler farms. Samples from 19 suspected outbreaks were collected. RT-PCR was conducted for genetic differentiation between very virulent strains and other circulating strains. Immunohistochemical staining applied on positive samples for describing the topographic distribution of viral antigens in bursa of Fabricius, thymus and spleen. Anti-chicken CD3 and CD79A markers were used to study the immune profiling of B and T cells. Among 19 flocks, 78.9% came out positive with RT-PCR. 57.9% were very virulent strains, 15.8% were classical or vaccinal strains, and 5.2% were coinfected. Viral antigens were most prevalent in bursa, followed by the spleen but not in thymic tissue. B cell significantly reduced in moderate and severe lesion scored bursae, while increased number of intra-bursal T cells was observed. In thymic cells, depletion of lymphocytes was obvious, although it was not associated with viral detection. Thymic sections revealed significant reduction in T-cells in moderate and severe lesion scores. However, mild affected tissue showed significant increase in T cells. In spleen, significant decrease in T and B cells was observed in moderate and severe scored samples. Very virulent isolates induced similar pathogenicity to typical UK661 strain. Providing detailed information on immune response against circulating strains may increase our understanding about the ability of the virus to frequently break through vaccination control. [ABSTRACT FROM AUTHOR]

Infectious bursal disease has hampered the development of commercial poultry production in Ghana, with outbreaks continually occurring despite the introduction of the harmonized national poultry vaccination protocol (HNPVP) that incorporates two types of live IBD vaccines. One major reported reason for these vaccination failures is the vaccine neutralization by maternally-derived antibodies (MDA). This study compared the antibody titres of layers vaccinated with the HNPVP to layers vaccinated with VAXXITEK HVT+IBD, a viral vectored vaccine. An agar gel immunodiffusion test and an indirect enzyme linked immunosorbent assay (ELISA) were used to detect and quantify antibodies. The results of this experiment show that high MDA did not affect VAXXITEK HVT + IBD as there was a measurable antibody response with high titre values. However, the delay before this antibody response and the resultant low antibody levels at the most susceptible period may create an opportunity for field infection. However high MDA interfere with and can neutralize live IBD vaccines even when they are applied strictly as advised in the HNPVP. It is therefore quite likely that a significant portion of the reported IBD vaccination failures in Ghana are due to failure of the HNPVP due to interference with MDA hence specific ‘farm-tailored’ vaccination schedules based on flock profiling, and recombinant vectored vaccines that have been shown to produce universal protection unaffected by high MDA may be the solutions to post vaccination outbreak commonly observed in Ghana. [ABSTRACT FROM AUTHOR]

Virus-infectious diseases are permanent threats and cause serious lost for chicken industry of our country. Recombinant chicken interferon alpha (rChIFN-α) were expressed successfully on yeast pichia pastorisand was functional antivirus. The objective of this study was determined recombinant chicken interferon alpha (rChIFN-α) effectiveness in 3-week-old chickens infected infectious bursal diseasevirus (IBDV).In the present study, we used 3-week-old chickens without IBDV antibodies. Each 3-week-old chickens were infected virulent Gumboro disease virus with dose of 5x104ELD50. After 24 hours infected virus, they were exposed to eye/nasal drops with one of doses 0.1 μg/chick; 1 μg/chick; 10 μg/chick or 100 μg/chick. The results suggested treatment with rChIFN-α 0.1 μg/chick, the chickens' protected and survival rate were 46.7% and 80% respectively. Group of chickens were treated rChIFN-α 1 μg / chick, the protected and survival rate of chickens respectively 60.0% and 86.7%; The same result with chickens were treated rChIFN-α 10 μg/chick and 100 μg/chick, the chickens' protected and survival rate were 66.7% and 93.3%, respectively. Meanwhile, the positive control group (chicken infected virus, untreated), unprotected chickens (infection rate was 100%) and survival rate was only 60,00%. The negative control (chickens uninfected viruses, untreated with rChIFN-α), completely uninfected and 100% survival chickens. The result suggested that rChIFN-α have effective treating Gumboro disease and depends on the dose used. In addition, the chickens' antibody titres shown that the chickens' immune response in rChIFN-α groups was not different than the chickens infected only Gumboro disease virus, suggested that rChIFN-α did not affect the chickens' immune response.

1. This study evaluated the effect of folic acid (FA) supplementation on the proinflammatory and antiviral molecular pathways of B-lymphocytes infected with a modified live IBDV (ST-12) mild vaccine strain during a timed post-infection analysis. 2. A chicken B-lymphocytes (DT-40) cell line was cultured in triplicate at a concentration of 5 × 105 cells per well in 24-well plates; and was divided into three groups: 1: No virus, FA; 2: Virus, no FA; 3: Virus + FA at a concentration of 3.96 mM. The experiment was repeated three times. 3. Cells in groups 2 and 3 were infected with a modified live IBDV (ST-12) mild vaccine strain at one multiplicity of infection (MOI: 1). After 1 hour of virus adsorption, samples were collected at 0, 3, 6, 12, 24 and 36 hours post-infection (hpi). 4. The modified live IBDV (ST-12) mild vaccine strain triggered a B-lymphocyte specific immune response associated with the upregulation of genes involved in virus recognition (Igß), virus sensing (TLR-2, TLR-3, TLR-4 and MDA5), signal transduction and regulation (TRIF, MyD88 and IRF7), and the antiviral effector molecules (IFN-α, OAS, PKR, and viperin). 5. FA supplementation modulated IBDV replication and regulated the proinflammatory and antiviral downstream molecular pathways. 6. In conclusion, the low virulent pathotype serotype I modified live IBDV (ST-12) mild vaccine strain was able to trigger and mount an immune response in chicken B-lymphocytes without affecting B-cell viability. FA supplementation modulated B lymphocytes response and improved their innate immune proinflammatory and antiviral response molecular pathways. [ABSTRACT FROM AUTHOR]

Background: Infectious Bursal Disease (IBD) is a highly infectious disease which causes huge economic losses to the poultry industry due to the direct impact of the illness and indirect consequences such as decreasing the general immunity of the flock, leaving it naive to other diseases. In Iraq, IBD is highly prevalent despite vaccination programs, yet studies on sequence diversity of the causative virus are still rare. Methods: A sample from Bursa of Fabricius from an IBD outbreak in a flock in the city of Najaf in Iraq was smeared on an FTA card. Amplicons of targeted regions in VP1 and VP2 genes were generated and sequenced. Sequences were then compared with other local and global sequences downloaded from GenBank repositories. Sequence alignment and DNA sequence analyses were achieved using MUSCLE, UGENE and MEGAx software. The molecular clock and sequence evolutionary analyses were applied using MEGAx tools. Results: The strain sequenced in this study belongs to a very virulent Infectious Bursal Disease Virus (vvIBDV) as the DNA and phylogenetic analysis of VP1 and VP2 gene sequences showed a mutual clustering with similar sequences belonging to vvIBDV genogroup 3. Analyses of the hyper variable region of VP2 gene (hvVP2) of IBDV isolates from Iraq indicates a presence of sequence diversity. Interestingly, the two vaccine strains Ventri IBDV Plus and ABIC MB71 that showed the highest sequence similarity to the local isolates in the hvVP2 region are not used in vaccination routine against IBDV in Iraq. Conclusion: Sequences of vvIBDV in Iraq are diverse. Remarkably, some of the available vaccine strains show high sequence similarity with local strains in Iraq; however, they are not included in the routine vaccination programs. Analysis of more samples involving more geographical regions is needed to draw a detailed map of antigenic diversity of IBDV in Iraq.

Background: Infectious Bursal Disease (IBD) is a highly infectious disease which causes huge economic losses to the poultry industry due to the direct impact of the illness and indirect consequences such as decreasing the general immunity of the flock, leaving it naive to other diseases. In Iraq, IBD is highly prevalent despite vaccination programs, yet studies on sequence diversity of the causative virus are still rare. Methods: A sample from Bursa of Fabricius from an IBD outbreak in a flock in the city of Najaf in Iraq was smeared on an FTA card. Amplicons of targeted regions in VP1 and VP2 genes were generated and sequenced. Sequences were then compared with other local and global sequences downloaded from GenBank repositories. Sequence alignment and DNA sequence analyses were achieved using MUSCLE, UGENE and MEGAx software. The molecular clock and sequence evolutionary analyses were applied using MEGAx tools. Results: The strain sequenced in this study belongs to a very virulent Infectious Bursal Disease Virus (vvIBDV) as the DNA and phylogenetic analysis of VP1 and VP2 gene sequences showed a mutual clustering with similar sequences belonging to vvIBDV genogroup 3. Analyses of the hyper variable region of VP2 gene (hvVP2) of IBDV isolates from Iraq indicates a presence of sequence diversity. Interestingly, the two vaccine strains Ventri IBDV Plus and ABIC MB71 that showed the highest sequence similarity to the local isolates in the hvVP2 region are not used in vaccination routine against IBDV in Iraq. Conclusion: Sequences of vvIBDV in Iraq are diverse. Remarkably, some of the available vaccine strains show high sequence similarity with local strains in Iraq; however, they are not included in the routine vaccination programs. Analysis of more samples involving more geographical regions is needed to draw a detailed map of antigenic diversity of IBDV in Iraq.

Infectious Bursal Disease (IBD), also called Gumboro, was disease which attacked cells in the bursa of fabricius, causing interference with the chicken's immune system or immunosuppressive. IBD was the one of viral disease that often attacks chickens in the field. The aim of this study was to determine the diagnosis of IBD by through at clinical symptoms and necropsy that can still be relevant on in the field. The diagnosis of IBD correctly, cheaply, easily and quickly in the field is very important to optimize the health care management and evaluation program. The method used was by observing clinical symptoms of broiler chickens in commercial farms suspected of contracting IBD and observing post-death organs (necropsy). The object of necropsy was 5 samples of broiler chickens from the farm. Data was analyzed descriptively. The results of this study was the broiler chickens that infected with IBD could be diagnosed through clinical symptoms and post-death organ changes, so that the diagnosis for IBD cases in the field used the observation of clinical symptoms and necropsy are still relevant.

Between July and September 2017, samples collected from six unvaccinated chickens in Namibia were shown to be positive for infectious bursal disease virus (IBDV) by RT-PCR. Partial sequence and phylogenetic analysis of the VP1 and VP2 genes from six viruses revealed that they all belong to the very virulent pathotype (Genogroup 3) and are genetically very similar to IBDVs identified in neighbouring Zambia. This is the first molecular characterisation of IBDV in Namibia and has implications on the control and management of the disease in the country.

The emergence of new infectious bursal disease virus (IBDV) variants can threaten poultry health and production all over the world causing significant economic losses. Therefore, this study was performed to determine IBDV molecular epidemilogy, VP2 gene variation, and corresponding pathological lesions in IBDV infected chickens in Turkey. For this, 1855 bursa of Fabricius samples were collected from 371 vaccinated broiler flocks. Atrophia and haemorrhages were seen in the bursa Fabricius of very virulent IBDV (vvIBDV) infected chickens. Partial VP2 gene was sequenced and phylogenetic, recombination, and evolutionary analyses were performed. 1548 (83.5%) out of 1855 of bursa of Fabricius samples were IBDV positive and 1525 of those could be sequenced. The recombination analysis did not detect occurrence of any recombination event among the Turkish strains. Among 1525 sequenced samples, 1380 of them were found to be classical strains. Among 1380 classical strains, 1317 were similar to IBDV 2512, 11 to Faragher 52/70, 40 to 228 E, and 12 to Lukert strain. Out of 1525 reverse transcriptase ploymerase chain reaction positive samples, 144 of them were found to be similar to vvIBDV-VP2 gene reported to GenBank previously. The phylogenetic tree performed on a broad sequence dataset demonstrated grouping of vvIBDV Turkish strains in three different clusters, including sequences collected also from Iraq and Kuwait (Cluster 1), Indian (Cluster 2), and a distinct Turkish-only cluster (Cluster 3). The evolutionary rate estimation on branches/clades including Turkish strain mirrored the expected one for RNA viruses and no significant differences were found among different considered branches. In conclusion, results of this study indicate that vvIBDV strains similar to those circulating in various countries in the Middle East are present and undergoing evolution in chickens from Turkish broiler flocks. This point needs to be taken into account in planning adequate control strategies. [ABSTRACT FROM AUTHOR]

This study was conducted to assess the effect of methanolic plant extract of some selected plants (Acanthus montanus, Spondiamombins and Mucunapruriens) on immune response in cockerel. One hundred and forty birds (140) were allotted to 7 groups (n=10) in this experimental unit and replicated twice. Birds were administered Spondiasmombin orally at 250mg/kg bw, Spondiasmombin at 500mg/kg bw, Mucunapruriens at 250mg/kg bw, Mucunapruriens at 500mg/kg bw, Acanthus montanus at 250mg/kg bw, Acanthus montanus administered orally to birds at 500mg/kg bw and distilled water and designated as Groups 1- 7 respectively. Birds were vaccinated against Gumboro twice at days 10 and 21 while Lasota vaccine was administered twice at days 14 and 28. Blood samples were collected brachial vein (wing vein) of the animal on days 9, 23 and 37 to obtain sera samples which were used for indirect haemagglutination assay (to detect Gumboro virus antibody) and days 13, 27 and 42 for sera samples used for Haemaglutination inhibition test (HI) (to detect Newcastle virus antibody). There were no significant differences (p>0.05) in the initial antibody titre among the birds for both IHA and HI. The highest antibody titre, 28.0 was found in birds administered with Acanthus montanus (500mg/kg) at day 42 for HI. The highest antibody titre for the IHA was found in birds administered with Acanthus montanus (500mg/kg) at day 37. The control birds had 23.5 and 23.7 at days 37 and 42 for IHA and HI respectively.From this study, A. montanus at 500mg/kg is recommended as adjuvant to gumboro and Newcastle vaccines in poultry. [ABSTRACT FROM AUTHOR]

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Nghiên cứu trình bày kết quả điều tra dịch tễ trên 64 ổ dịch tại An Giang, Cần Thơ, Hậu Giang, Vĩnh Long. Kết quả lấy mẫu huyết thanh xét nghiệm phản ứng ELISA như sau: 30 đàn có kết quả dương tính với virus Gumboro chiếm tỷ lệ 46,9%. Bệnh Gumboro xảy ra trên gà chủ yếu 21 - 42 ngày tuổi (59,0%), > 42 ngày có tỷ lệ mắc bệnh thấp hơn (28,0%). Gà nuôi theo phương thức thả hoàn toàn có tỷ lệ mắc bệnh (29,2%) thấp hơn so với gà nuôi nhốt hoàn toàn (60,00%) và bán chăn thả (57,1%). Giống gà Nòi có sức đề kháng tốt hơn so với gà Lương Phượng, Tàu Vàng.

Between July and September 2017, samples collected from six unvaccinated chickens in Namibia were shown to be positive for infectious bursal disease virus (IBDV) by RT-PCR. Partial sequence and phylogenetic analysis of the VP1 and VP2 genes from six viruses revealed that they all belong to the very virulent pathotype (Genogroup 3) and are genetically very similar to IBDVs identified in neighbouring Zambia. This is the first molecular characterisation of IBDV in Namibia and has implications on the control and management of the disease in the country. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the effect of a new infectious bursal disease (IBD) immune complex vaccine on immune system response in both specific pathogen-free (SPF) and commercial birds. Evaluation of response to the vaccination in the two experiments was done by histopathological examination and serology. The results of this study have shown that immune complex vaccine with the V877 strain is quite safe in White Leghorn SPF birds in which there has been no participation of maternal antibodies. In commercial birds was also observed that the immune complex vaccine with the V877 strain acted synergistically with different levels of passive antibodies and the vaccine virus began to replicate as passive immunity decreased to provide the animal active immunological response. [ABSTRACT FROM AUTHOR]

Over a span of nearly 4 yr, 246 bursal tissue samples were collected from Brazilian commercial broiler flocks (Gallus gallus) throughout the country and imprinted to sample collection cards (Flinders Technology Associates (FTA) cards). A total of 75 infectious bursal disease virus (IBDV) strains was successfully detected from the FTA card imprints and were submitted for further identification and molecular characterization. Nucleotide and predicted amino acid sequences of the IBDV surface protein VP2 were used to identify strains of the virus and place them into phylogenetic groups. The amino acids across the hypervariable region of VP2 in this study varied, but around half of all positive samples were classified as vaccine virus. The IBD viruses fell into 3 categories: variant IBDV, classic IBDV (vaccine), and very virulent (vv) IBDV. The samples were collected according to the 3 different vaccination strategies used in broilers: vectored vaccine, antigen-antibody complex vaccine, and conventional live vaccine. The genetic profile and frequency of the strains recovered from the flocks were highly dependent on the vaccination program. This information helps us gain a better understanding of the current landscape of IBD in Brazil and provides additional scientific data to support selection of the most effective vaccination strategies, products, and practices to prevent disease. [ABSTRACT FROM AUTHOR]

Infectious bursal disease is a severe acute viral disease of young chickens, affecting mainly the B-lymphocytes in the bursa of Fabricius, leading to severe immunosuppression as a result of the death of lymphoid cells. In the bursa infected with infectious bursal disease virus, viral replication is associated with apoptosis of lymphoid cells, inflammatory change and atrophy. Vaccination has appeared to be a crucial factor for control, with live attenuated vaccines being the most used. However, the apoptotic effect of these vaccines on the bursa has not been tested. We determined the apoptotic effect caused by the most used vaccines in local production on the bursa of Fabricius cells and the correlation with histological changes. In this study, it was demonstrated that apoptosis levels in the vaccinated groups were higher than those observed in the non-vaccinated birds leading to the conclusion that the action of the live virus vaccine strains modifies the boundary of the bursa and shapes processes of cell death by apoptosis. In contrast to other studies, the vaccine strains used did not show the phenomenon of bursal atrophy during the experimental period. [ABSTRACT FROM AUTHOR]

Nghiên cứu huyết thanh học được thực hiện nhằm khảo sát tỷ lệ nhiễm virus Newcastle và Gumboro trên gà thả vườn ở xã Thông Hòa. Tổng số mẫu huyết thanh được thu thập là 93, các mẫu được lấy từ gà chưa tiêm phòng vắc xin để kiểm tra kháng thể. Kháng thể kháng virus Newcastle được kiểm tra qua xét nghiệm ức chế ngưng kết hồng cầu (HI) và kháng thể kháng virus Gumboro được kiểm tra bằng xét nghiệm ELISA. Trong tổng số 93 mẫu huyết thanh có 72 (77.4%) mẫu dương tính với kháng thể kháng virus Newcastle. Tỷ lệ nhiễm virus Gumboro là 68.8%, trong khi đó tỷ lệ nhiễm ghép Newcastle và Gumboro là 54.8%. Nghiên cứu cho thấy có sự lưu hành của virus Newcastle và Gumboro trên đàn gà khảo sát.

Tổng số 20 mẫu bệnh phẩm (túi Fabricius) được thu thập từ 16 đàn gà bệnh trong tỉnh (những đàn có triệu chứng và bệnh tích đặc trưng của bệnh Gumboro). Phân tích di truyền cho thấy tất cả các mẫu đều dương tính với vius gây bệnh Gumboro (infectious bursal disease virus). Vật liệu di truyền của virus được sử dụng để xác định trình tự chuỗi nucleotide của vùng siêu biến đổi gen VP2, sau đó những trình tự này được so sánh với trình tự của 04 mẫu virus vaccine đang sử dụng tại Trà Vinh. Kết quả cho thấy sự khác biệt về di truyền của chủng virus đang lưu hành với một số chủng virus vaccine như sau: dựa vào trình tự gen và phân tích phả hệ di truyền cho thấy các mẫu phân lập thuộc phân nhóm có độc lực cao và có quan hệ gần với các chủng virus cường độc khác của Việt Nam (G202, GPT, GT1ST, GTG25) và Trung Quốc (QX110609, WM12061, Xin1). Mức độ tương đồng về amino acid của chủng virus đang lưu hành với mẫu virus vaccine Gumboro Navetco – Việt Nam là 90,4%, với vaccine BUR-706 của MERIAL – PHÁP là 91,8%, và với vaccine IBD BLEN của MERIAL – Mỹ là 95,2%, đặc biệt tương đồng cao với mẫu virus vaccine Medivac Gumboro A của Medion – Indonesia (97,9%). Kết quả này chứng tỏ vaccine Medivac Gumboro A của Medion – Indonesia có khả năng bảo hộ cao hơn 3 loại vaccine còn lại.

Fifty Bursa of Fabricius (BF) were examined by conventional optical microscopy and digital images were acquired and processed using Matlab® 6.5 software. The Artificial Neuronal Network (ANN) was generated using Neuroshell® Classifier software and the optical and digital data were compared. The ANN was able to make a comparable classification of digital and optical scores. The use of ANN was able to classify correctly the majority of the follicles, reaching sensibility and specificity of 89% and 96%, respectively. When the follicles were scored and grouped in a binary fashion the sensibility increased to 90% and obtained the maximum value for the specificity of 92%. These results demonstrate that the use of digital image analysis and ANN is a useful tool for the pathological classification of the BF lymphoid depletion. In addition it provides objective results that allow measuring the dimension of the error in the diagnosis and classification therefore making comparison between databases feasible.Cinquenta Bursa de Fabrícius (BF) foram examinadas através de microscopia óptica convencional e imagens digitais foram obtidas e processadas através do software Matlab® 6.5. Redes Neurais Artificiais (ANN) foram geradas com a utilização do software Neuroshell® Classifier, e os dados das análises óptica e digital foram comparados. A ANN classificou corretamente a maioria dos folículos, atingindo sensibilidade e especificidade de 89% e 96%, respectivamente. Quando os folículos foram agrupados de forma binária houve um aumento da sensibilidade para 90% e obteve-se um valor máximo para a especificidade de 92%. Estes resultados demonstram que o uso da análise digital de imagem associada à ANNé uma ferramenta bastante útil para a classificação patológica da depleção linfóide da BF. Além disso, fornece resultados objetivos que permitem medir a dimensão do erro classificatório, tornando possível a comparação entre distintos bancos de dados.

In this study, antibody titer obtained from the outbreak of the infection bursal disease (IBD) was compared with the titer obtained from live intermediate vaccines by indirect haemagglutination (IHA) test in broiler chicks. A total of 450 one day old Cobb chicks were divided into 3 groups each containing 150 chicks and were kept for 42 days in the same rearing conditions. Chicks in groups 1 and 2 received Bursin-2 and D-78 vaccines respectively via drinking water n days 14 and 21. The rest of the chicks were kept as the controls (group 4) and did not receive any vaccine against the IBD. Serum samples were collected from all birds 2 weeks after the second IBD vaccination. Additional 150 serum samples were also collected from 3 broiler flocks that were affected by IBD and had a history of vaccination by the previously mentioned method, two weeks after the last clinical sings were observed (group 3). Antibody titer of the samples against the IBD virus were determined by the IHA test and the results were evaluated using ANOVA and SPSS software. The mean antibody titer obtained from Bursin-2 and D-78 vaccines were 3.19 and 3.21 respectively which is less than the titer of 6 needed for protection against the disease. The antibody titer in affected flocks was 7.19. comparison of the mean titer of the two vaccines did not show any significant difference but there was significant difference between the titer obtained from each vaccine and that of the effected flock (p

The aim of this study was to evaluate the possible protective effect of preparation which synthesized in Vitebsk State Academy of Veterinary Medicine adsorbent (Toxicom) 5g\kg diet against the toxic effects of mixed mycotoxins in growing broiler chickens. Total 75 chicks, one week age, were divided into 5 treated groups,15 birds for each. The first group (G1) fed a contaminated ration with mycotoxin and supplemented with toxicom 5g/kg of diet and vaccinated with gumboro vaccine at 15 and 22 days of age. The second group (G2) was fed a ration contaminated with mycotoxin and vaccinated with gumboro vaccine at 15 and 22 days of age and not supplemented with toxicom. The third group (G3) was fed intact broiler ration and vaccinated with gumboro vaccine at 15 and 22 days of age. The fourth group (G4) was only fed a contaminated ration with mycotoxins. The fifth group (G5) was fed intact broiler ration as a control group. The diet was naturally contaminated with many mycotoxins and analyzed by ELISA and the level of mycotoxins were as follows : Aflatoxin B1 0.001 mg/kg, Dezoxivalenol 1.24 mg/kg, Zearalenon 0.068 mg/kg, Ochratoxin 0.005 mg/kg, T2 toxin 0.09 mg/kg, Fuminisen B1 0.2 mg/kg. The antibody titers for Infectious Bursal Disease vaccine (IBDv) was conducted by ELISA. It was concluded that this preparation which synthesized in Vitebsk State Academy of Veterinary Medicine is protect chickens body weight and decrease the effect of mycotoxins in comparison with the other groups and recommended for using as adsorbent in Republic of Belarus.

In the current study, lipid peroxidation, antioxidant enzymes, antioxidant vitamins, oxidation products of nitric oxide and some biochemical parameter levels in chicken with infectious bursal disease were investigated. Thirty chicken were used in the study, 7 in a control group of healthy individuals and the other 23 chickens were infected naturally. The level of advanced oxidation protein products (AOPP) was not affected by the treatment. Vitamin C (P<0.01), nitrite (P<0.01), catalase (P<0.001) and superoxide dismutase (P<0.001) levels were significantly decreased. The levels of malondialdehyde and nitrate increased significantly (P<0.001), while the amounts of ALT (P<0.05) and Albumin (P<0.001) decreased. We also found that changes in glucose, AST, triglyceride and total protein levels were not affected. On the other hand, increases in the levels of LDL (P<0.01), cholesterol and HDL (P<0.05) were significant. [ABSTRACT FROM AUTHOR]

This paper describes the effects of a strong type of vaccine - Moulthrop G603 º and an intermediate-plus type of vaccine - 228E º in meat-type chickens challenged with a very virulent strain of infectious bursal disease virus (vvIBDV). Blood samples and bursa of Fabricius were taken weekly up to 42 days of age. It was concluded that bursa of Fabricius weight, bursa weight:body weight ratio, body weight and antibody titer evaluated before and after challenge with vvIBDV were not enough to consistently and conclusively differentiate or estimate the protection given by vaccination. Quantitative evaluation of injury intensity and the number of altered lymphoid follicles revealed that Moulthrop G603 caused moderate microscopic lesions in one out of seven birds vaccinated at 14 days of age, while 228E vaccine did not induce IBD-typical microscopic lesions in the bursa of Fabricius. Good protection against bursal microscopic lesions was obtained when a strong type of vaccine was used before challenging with vvIBDV. It was concluded that quantitative evaluation of microscopic lesions might be useful to measure the injury induced by vaccinal IBDV, as well as the level of protection and/or immunosuppression induced by IBDV challenge in vaccinated and non-vaccinated chickens.

The study was conducted to test the pathogenic effect of six commercially available infectious bursal disease (IBD) vaccines claimed to be intermediate in their pathogenicity. Three week old chickens were inoculated with these vaccines. The pathogenic effects of the IBD vaccines were evaluated by hemorrhages on the thigh and breast muscles, bursa weight to body weight ratio and virulence; two of the strain were found to be highly virulent; two others were moderate and two could be classified as mild.

Qua điều tra dịch tễ đối với 24 ổ dịch tại huyện An Phú-tỉnh An Giang, lấy huyết thanh tại các ổ dịch để xét nghiệm bằng phản ứng ELISA, qua đó thu được kết quả như sau: Kết quả kiểm tra 24 ổ dịch có 9 đàn cho kết quả dương tính với virus Gumboro chiếm tỷ lệ 33,33%. Bệnh Gumboro xảy ra chủ yếu ở lứa tuổi 19 - 42 ngày chiếm (57,14 %), gà ở lứa tuổi > 42 ngày có tỷ lệ mắc bệnh thấp hơn (11,11%). Gà nuôi theo phương thức thả hoàn toàn có tỷ lệ mắc bệnh Gumboro (25,00%) thấp hơn so với gà nuôi nhốt hoàn toàn (60,00%) và bán chăn thả (33,33%). Giống gà Nòi có sức đề kháng đối với bệnh Gumboro tốt hơn so với gà Lương Phượng.

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Nghiên cứu hiệu quả phòng bệnh của bào tử Bacillus subtilis biểu hiện interferon alpha gà (ChIFNa- B. subtilis) trong phòng bệnh Gumboro cho gà được thực hiện trên giống gà 3 tuần tuổi. Thí nghiệm được thực hiện bằng thử nghiệm cho mỗi gà uống 100 ?g bào tử ChIFNa- B. subtilis, sau đó công cường độc virus Gumboro độc lực cao với 4 x 104 ELD50, đồng thời so sánh hiệu quả của ChIFNa chuẩn với liều 104UI. Kết quả thử nghiệm cho thấy B. ChIFNa- B. subtilis có khả năng phòng bệnh Gumboro với tỷ lệ bảo hộ là 77,08% cao hơn so với tỷ lệ bảo hộ bởi ChIFNa (66,67% và so với đối chứng B. subtilis (12,50%). Kết quả thí nghiệm chứng minh ChIFNa- B. subtilis có tiềm năng trong việc phòng bệnh Gumboro trên gà.

En Venezuela, la incidencia de enfermedades respiratorias virales e inmunosupresoras son dos de los mayores problemas en la industria avícola nacional, y hasta el momento no se cuenta con suficiente información epidemiológica al respecto que ayude a establecer medidas de control, por lo que el objetivo de esta investigación fue de determinar serológicamente la presencia de anemia infecciosa aviar, reovirus y gumboro, y su relación entre ellas, así como determinar el nivel de anemia en las aves evaluadas. Se tomaron muestras de aproximadamente 14 a 15 aves, de forma semanal adiferentes edades (1, 7, 14, 21, 28, 35, y 42 días), en tres granjas comerciales, tomándose un total de 295 aves. Los títulos de anticuerpos se midieron a través de la prueba ELISA, y el nivel de anemia, por la técnica de microhematocrito. Se detectaron porcentajes de anticuerpos séricos: 90,8% (268/295) para anemia infecciosa aviar; 82,4% (244/295) para reovirus y 97% (286/295) para la enfermedad infecciosa de la bursa. En cuanto a los valores de hematocrito se encontró en forma general que, el 19,6% (58/295) de las aves evaluadas presentaron anemia, mostrando valores de hematocrito entre 20 y 27%. Se observó una correlación positiva altamente significativa entre la anemia infecciosa aviar y los otros virus inmunosupresores estudiados, con gumboro (r=0,437; P menor 0,0001) y reovirus (r=0,312; P menor 0,0001). Los resultados obtenidos en este trabajo permiten demostrar la presencia del virus de la anemia infecciosa aviar en pollos de engorde en la región, de manera aislada o asociada con reovirus y gumboro, que pudiesen estar afectando en forma subclínica o clínica las granjas avícolas zulianas.

The first target organ damaged by infectious bursa virus disease (IBVD) is the bursa, manifested in severe depletion of the B cells. However, this depletion depends on the regions of the lymphoid organs involved in the infection. Based on the existing relationship between the morphometry of the lymphoid organs and the inmunocompetence of the birds, it is interesting to observe possible effects from immunomodulators, vitamins and amino acids on the immune response for Gumboro (IBD) disease. In the lymphoid organs (swindle, spleen and bursa), the following parameters were evaluated until the first 8 weeks of age: weight of the bird, weight of each organ and serology for the Gumboro entity at 5 and 9 weeks. They were divided into 2 groups with the same handling (accommodation, feed and environment), but with different treatments. Group A (test J8), consisting of 55,062 birds, was given an immunomodulators during the first 3 days of life and 2 days after each application of the Gumboro vaccine. The vitamins and amino acids were administered from the fourth to the sixth day and 2 days following the change in food (pre-initiation and initiation phases). Group B (Control j7), consisting of 55,484 birds, was administered liver protector. Serological samples were taken at 5 and 9 weeks of age. In conclusion, the use of the immunomodulator, vitamins and amino acids during the reception protocol produces benefits observed in better consumption, weight, uniformity and proper development of the immune system. [ABSTRACT FROM AUTHOR]

Gumboro disease is caused by the infectious bursal disease virus (IBDV) which rapidly destroys immature B-lymphocytes of bursa of Fabricious, and causes immune suppression and high mortality in commercial broiler farms in Bangladesh. To investigate the possible effect of IBDV on lymphocytes and its distribution in the major lymphoid organs, bursa of Fabricious including spleen and thymus of naturally Gumboro-infected broilers, a research was conducted in the Department of Anatomy and Histology, collaboration with the Department of Pathology, Bangladesh Agricultural University, Bangladesh. Bursa of Fabricious, spleen and thymus of 21-days-old Gumboro-infected and non-infected broilers of same age (control) were routinely processed and stained by hematoxylin and eosin to examine the distribution of lymphocytes in the major lymphatic organs as well as quantified the number of lymphocytes under high power magnification field and compared with those of control. The number of lymphocytes in bursa of Fabricious, spleen and thymus of Gumboro-infected broilers were 27.20 ± 1.53, 66.50 ± 2.70 and 79.30 ± 3.92 whereas 121 ± 3.82, 89.90 ± 2.09 and 106.30 ± 4.07 were in non-infected control respectively. The numbers of lymphocytes were significantly (p < 0.05) lower in all lymphatic organs of Gumboro-infected broilers than those of non-infected control. The significant numbers of lymphocytes decrease in spleen and thymus suggest that IBVD not only destroy lymphocytes in bursa of Fabricious, but also in spleen and thymus and thus may severely suppress the immune response of IBVD affected broilers. [ABSTRACT FROM AUTHOR]

The present study was conducted to evaluate the changes of acute phase proteins (APPs) in healthy and infectious bursal disease virus (IBDV)-infected chicks. Blood samples were taken from 20 healthy chicks as control group and 45 and 20 chicks with mild and severe clinical signs of IBDV, respectively. Sera were isolated and measurement of haptoglobin (Hp), ceruloplasmin, serum amyloid A (SAA), and fibrinogen were done for all chicks using validated methods. Results showed significant differences in ceruloplasmin and SAA between healthy and infected chicks ( P < 0.05). Sera of infected chicks showed a significant decrease in ceruloplasmin level but a significant increase in SAA level ( P < 0.05). These differences were more prominent in severely infected chicks than in mildly infected chicks. There were no significant differences in fibrinogen and Hp between healthy and infected chicks ( P > 0.05). It can be concluded that in naturally occurring gumboro, a significant decrease in ceruloplasmin and a significant increase in SAA are expected. Among the APPs measured in this study, SAA appears to be the most sensitive parameter. [ABSTRACT FROM AUTHOR]

The article focuses on a study which evaluated follicular lymphoid depletion in the Bursa of Fabricius (BF), an alternative using digital media analysis and artificial neural networks (ANN). Using Neuroshell Classifier software, the ANN was generated and the optical and digital data were compared. Majority of the follicles were classified correctly using the ANN, reaching sensibility and specificity of 89% and 96%, respectively. Study results indicate that the use of digital image analysis and ANN is a useful tool for the pathological classification of the BF lymphoid depletion.

Abstract: The objective of this study was to describe the spatial and temporal dynamics of the 1999 outbreak of acute clinical infectious bursal disease (IBD) in broiler chicken farms in Denmark. The analysis was performed using data from all broiler farms located in the Jutland peninsula and the island of Funen (168 municipalities). The Moran''s index I, K-functions and scan statistics were used to describe the dynamics of the epidemic. In addition, spatially correlated survival analyses were performed and the posterior frailties were mapped to identify areas with high or low survival times. From January to October 1999, a total of 43 farms (81 flocks) out of a total of 299 farms (2970 flocks) in 110 municipalities were infected with IBD. The outbreak developed more or less simultaneously in two regions, one in the north and the other in the center of the study area. The space–time descriptive methods suggested that the cases were more likely to occur during a short period of time and over relatively short distances, indicating that local factors facilitated the spread of the virus. For instance, the highest risk, as estimated by the K-function, was within 20km and 20 days. The risk of transmission peaked in July and remained high until the end of the study. The spatially correlated survival analysis identified municipalities with low survival times that roughly corresponded to the clusters found using scan statistics. The analysis for the full hierarchical structure of the dataset identified variation (i.e. clustering) at the farm and municipality levels. [Copyright &y& Elsevier]

A total of 50 day - old broiler chicks were divided equally into two groups and treated with Lactobacillus salivarus (L S) as follow Group 1: given 3.2X108 cfu/ ml of LS in crop at day 1 of age. Group 2:Untreated control The two groups were vaccinated against Newcastle disease vaccine (ND vac) Lasota strain at age 10, 21, and 35 days direct in the crop. The groups were vaccinated in the crop against Gumboro vaccine (G vac) leukert strain at 5, 14 and 24 day of age. Haemagglutination inhibition test was used and determine antibodies titer (Abt) of (ND vac) and the agar gel precipitating test to 19, 29 and 39 of the chick's age. The result showed significant (p < 0.05) increase in Abt most of the weeks in the first group compared with second groups The performance results showed significant (p < 0.05) increase in the weight, weight gain , feed consumption and feed conversion ratio for chicks treated with LS. It was concluded that oral administration of Lactobacillus salivarus to day – old chicks has a beneficial effect on immune response to ND vac and G vac and on chick's performance.