Infectious Bursal Disease Vaccine Research Articles

Research Note: The infectious bursal disease (Gumboro disease) vaccination scheme affects the quantitative and qualitative carcass characteristics and the immune response of Ross 308 broiler chickens

After different vaccinations, the study aimed to assess carcass composition, meat quality, and the level of the infectious bursal disease antibody titers in broiler chickens. In the experiment, 4 (30 chicks per group, 120 total) groups of Ross 308 broiler chickens (males and females) were included. Then, they were vaccinated at the hatchery. Group I was immunized against infectious avian bronchitis (IB) and Newcastle disease (ND) using vaccine A (20 mL/100 birds) and vaccine B (20 mL/100 birds), respectively, with injectable vaccine C (0.2 mL/each) targeting Infectious bursal' and Marek's diseases (MD). Group II received the same vaccinations for IB and ND, with separate injectable D vaccines for MD (0.2 mL/unit) and E for infectious bursal' disease (0.2 mL/each). Group III was similarly vaccinated for IB and ND; however, they received only vaccine D (0.2 mL/each) for MD, and on d 23, vaccine F was administered via drinking water against Gumboro disease (0.05 mL/each). Group IV served as the control and was not vaccinated. Ten carcasses from each group on d 42 were taken for carcass composition analysis and meat quality, including pH, color, and water-holding capacity (WHC). During rearing, on d 14, 28, and 42, blood was collected to determine the level of antibodies against infectious bursal' disease. Additionally, hematocrit (HCT), hemoglobin (HGB), and red blood cells were analyzed. In group I, a higher bursa of Fabricius weight than in the other groups was found (P < 0.001), and the liver weight was lower compared to group II (P = 0.020). In breast muscle, the pH24 was higher in the control group than in group I (P = 0.036). Lightness (L*) in breast and leg muscles from group I was higher than in group II (P < 0.05). WHC was higher in group I than in group II (P = 0.025). The antibody titers of infectious bursal' disease was higher in group I on d 28 than in other groups (P < 0.05). Vaccine C (1 dose 0.2 mL/1 bird) of the reconstituted vaccine with the live recombinant virus strain vHVT013-69, not less than 3.6 - 5.0 log10 PFU) had a beneficial effect.

Postbiotic-based recombinant receptor activator of NF-κB ligand enhanced oral vaccine efficiency in chicken

Functional M cells are differentiated by receptor activator of NF-κB ligand (RANKL) and capture of luminal antigens to initiate immune responses. We aimed to use postbiotic-based recombinant chicken RANKL (cRANKL) to promote M cell differentiation and test the efficacy of oral vaccines. Chicks were divided into three groups that were administered phosphate-buffered saline (PBS), cell extracts of wild-type Lactococcus lactis subsp. lactis IL1403 (WT_CE), or cell extracts of recombinant L. lactis expressing cRANKL (cRANKL_CE). The expression of the M cell marker was measured, and the gut microbiome was profiled. The efficiency of the infectious bursal disease (IBD) vaccine was tested after 12 consecutive days of administering cRANKL_CE. The chickens that were administered cRANKL_CE (p = 0.038) had significantly higher Annexin A5 (ANXA5) mRNA expression levels than those in the PBS group (PBS vs. WT_CE, p = 0.657). In the gut microbiome analysis, no significant changes were observed. However, the relative abundance of Escherichia-Shigella was negatively correlated (r = − 0.43, p = 0.019) with ANXA5 mRNA expression in Peyer’s patches. cRANKL_CE/IBD (p = 0.018) had significantly higher IBD-specific faecal IgA levels than PBS/IBD (PBS/IBD vs. WT_CE/IBD, p = 0.217). Postbiotic-based recombinant cRANKL effectively improved the expression of M cell markers and the efficiency of oral vaccines. No significant changes were observed in the gut microbiome after administration of postbiotic-based recombinant cRANKL. This strategy can be used for the development of feed additives and adjuvants.Key points• Postbiotic-based recombinant cRANKL enhanced the expression of ANXA5 in chicken.• The relative abundance of Escherichia-Shigella was negatively correlated with ANXA5 expression.• Postbiotic-based recombinant cRANKL effectively improved the efficiency of oral vaccine.

Immunostimulating potentials of methanolic extract of &lt;i&gt;Plectranthus parviflorus&lt;/i&gt; in chickens vaccinated against Newcastle disease and Infectious bursal disease

Outbreaks of Newcastle disease (ND) and Infectious Bursal disease (IBD) have been reported in vaccinated poultry flocks in many countries highlighting the need for the administration of immunostimulants to improve immunity in such birds. The immunomodulatory effects of methanol leaf extract of plectranthus parviflorus on ND and IBD antibody titre was investigated. One hundred day-old cockerels were randomly assigned into five groups each, A-E and A1-E1 for Newcastle disease and Infectious bursal disease studies respectively. Groups A and A1 were control groups and received water only while groups B and B1 received LaSota and IBD intermediate plus ® vaccine respectively. Groups C and C1, D and D1 were administered 100mg/kg and 200mg/kg of Plectranthus parviflorus orally for three days before vaccination respectively, while groups E and E1were given 100mg/kg of the extract orally three days post vaccination. Blood samples were obtained via jugular vein at day-old and 14 days as well as on days 7, 14 and 21 post vaccination. Haemagglutination- inhibition (HI) test and enzyme linked immunosorbent assay (ELISA) were used to assay the antibody titre against ND and IBD respectively. A decline in maternal antibody over 14 days was observed for antibody titre against Newcastle disease and infectious bursal disease from 6.1 to 1.8 geometric mean (log2) and (1043.37±2.1) to (524.48±2.7) respectively. Group D was observed to have a significant titre value of 2.3 and 3.7 geometric mean (log2) 14 and 21 days post ND vaccination while group D1 also had a significant increase (1037.90±3.6) titre 14 days post-vaccination. This study showed that plectranthus parviflorus extract had a significant effect on Newcastle disease and Infectious bursal disease humoral response when administered orally at 200mg/kg before vaccination with ND and IBD vaccines respectively.

Immuno-protective effect of commercial IBD vaccines against emerging novel variant infectious bursal disease virus in specific-pathogen-free chickens.

Infectious bursal disease (IBD) is an important viral poultry disease that vaccination can control. This study examined the immune protection of immune-complex (Vaccine A) and attenuated live (Vaccine B) IBD vaccines in specific-pathogen-free (SPF) chickens against a novel Malaysian variant IBD virus (vaIBDV) challenge. One-day-old (n =75) SPF chickens were divided randomly into the following three groups of 25 chicks each: Control, Vaccine A, and Vaccine B groups. The vaIBDV strain, UPM1432/2019, was used for the challenge at 21 and 28days post-vaccination (dpv). Five birds from unchallenged and challenged groups were sacrificed seven days post-challenge, and blood, bursa, spleen, and cloacal swabs were collected. The IBD antibodies (Abs), lymphoid lesions, and viral load were determined. The UPM1432/2019 virus induced bursal damage in vaccinated SPF chickens despite Ab titers. The mean Ab titers of the Vaccine A challenged group were significantly lower (p < 0.002) than in the unchallenged group at 28 dpv. The bursal indices of the vaccinated unchallenged groups did not differ significantly from those of the vaccinated challenged groups (p = 0.94). Microscopically, the bursae of the challenged groups showed significant atrophy. The bursal lesion score was higher (p < 0.05) in the control and Vaccine B challenged groups than the Vaccine A challenged group. The challenged group had a higher viral load than the vaccinated groups (p < 0.001). Neither vaccine fully protected against a vaIBDV challenge, highlighting the limitations of current vaccines and the need for further research.

Cytokines, Serological, and Histopathological Assessment of Recombinant Vaccination Strategies for Combatting Infectious Bursal Disease in Broiler Chickens.

Infectious bursal disease (IBD) represents a greatly transmissible viral disease found worldwide, causing significant health and production challenges in young chickens. The aim of this research was to assess the immune reaction induced by different vaccines targeting IBD. These vaccines included recombinant (Vac1; HVT-IBD vector), immune complex (Vac2; Bursa-Plex®), and intermediate plus (Vac3; Bursine plus) IBD vaccines. Our assessment relied on serological and histopathological analyses, as well as the pattern of immune-related cytokine expression in the bursal tissue. The vaccinated groups, along with a control positive (CP) group, were subjected to a vvIBDV challenge on their 28th day of life, while the control negative (CN) group received a mock vaccination with PBS. Our study revealed that Vac1 resulted in the most favorable growth performance, as well as maintained normal liver and kidney function, mitigating the impact of IBDV infection. Serological analysis using VP2 ELISA kits indicated that Vac1 induced the strongest immunological response among all vaccines. Histopathological examination demonstrated that Vac1 caused minimal lymphoid depletion observed in the lymphoid organs, followed by Vac2. Analysis of cytokine expression profiles showed significant upregulation in all vaccinated groups, particularly Vac1, during the pre-challenge period. Following IBDV infection, Vac1 resulted in a noteworthy increase in the expression of IL2 and IFN-γ, Vac2 showed a significant upregulation in TNF-α and granzyme, and both Vac1 and Vac3 exhibited increased levels of IL1β and IL10. In conclusion, our study suggests that the various vaccines triggered immune responses against IBD through both humoral and cell-mediated immunity. However, recombinant followed by immune complex vaccines appeared to induce more robust immunity while also being safer for broiler chickens in contrast to the intermediate plus vaccine.

Efficacy of Christmas melon and neem extracts on the growth performance, carcass characteristics and cost benefit of broiler chickens as alternative to new castle and infectious bursal disease vaccines

The experiment was carried out to investigate the effects of Christmas melon and Neem extract on the growth performance, carcass characteristics, organ characteristics and cost benefits of broiler chickens. The experiment employed a completely randomized design. All data generated were subjected to analysis of variance. A total of one hundred day old Abor Acre broiler chickens were used in this study, the birds were weighed on arrival to the brooding pen to know the initial weight of the birds; the birds were fed with formulated broiler diets for both starter and finisher phases for the 56 days the experiment lasted. The birds were divided in to 4 treatments, replicated five times with 5 birds per replicate. Treatment I the control diet (placed on normal Lasota and Gumboro vaccines), treatment II were placed on Christmas melon extract (CME), Treatment III were placed on Neem Extract (NE), Treatment IV were on mixture of 1:1 Christmas melon and Neem Extract. All the parameters examined on the performance had statistical similar values when compared (p&gt;0.05) with the birds on the control. The production cost of birds on Treatment II, III, and IV reduced but not statistically (p&gt;0.05) when compared to the control birds. Furthermore, the birds on treatment II were more profitable when compared to other treatments. It was concluded that replacement of Lasota and Gumboro vaccines with Neem Extract and Christmas melon in broiler production enhanced the growth performance and antioxidant capacity of the birds without any deleterious effect on their health status.

The effect of micronutrient supplementation on bioavailability, antioxidants activity, and weight gain in response to Infectious Bursal Disease vaccination in commercial broilers

The effect of supplementing organic selenium and zinc on bioavailability, oxidative stress, weight gain in commercial broilers was studied. A total of 180-day-old chicks were divided into six groups: NSUV (Not supplemented, unvaccinated), NSV (Not supplemented, vaccinated), VS (vaccinated, supplemented selenium), VZ (vaccinated supplemented zinc), VSZ (vaccinated supplemented selenium and zinc), UVSZ (unvaccinated supplemented selenium and zinc). 1 mg/kg selenium and 60 mg/kg zinc were added to the feed of supplemented groups. The concentration of selenium (0.05 ± 0.00 mg/L) in VS and zinc (0.66 ± 0.13 mg/L) in VZ were lower on day 27 post-vaccination compared to day 10 (VS= 0.07 ± 0.01 mg/L; VZ= 1.46 ± 0.30 mg/L). Glutathione peroxidase and catalase concentrations were highest in the supplemented groups compared to unsupplemented groups on day 27 post vaccination, expressing a similar trend with the micronutrients. There was no difference (P ≥ 0.05) in the glutathione concentration between all groups except on day 27 post vaccination where SZV group was significantly higher (P=0.02) compared to the NSV group. Catalase concentration was significantly decreased in the NSV group compared to SZV (P=0.04) on day 27 post vaccination. The NSV group (1.64 ± 0.13 kg) weighed significantly lower (P=0.02) than the VSZ (2.00 ± 0.12 kg) in the fifth week, while on the sixth week, the SZV group gained the highest weight (2.04 ± 0.18 kg). The supplementation of organic selenium and zinc in broilers increased the serum micronutrients bioavailability, decreased oxidative stress, increased weight gain, thus, enhancing immunity in the broilers.

Effects of Dietary Supplementation of Phytogenic Feed Additives on Broiler Feed Conversion Efficiency and Immune Response against Infectious Bursal Disease Vaccine

The ban on antibiotic growth promoters in livestock feeding has encouraged the utilization of phytogenic feed additives. These phytogenics recently attracted much attention and are generally recognized as residue-free ideal feed additives in animal Production. The current study was conducted to investigate the effects of the phytogenic herbs on feed intake, feed conversion ratio, and immune responses associated with the infectious bursal disease (IBD) vaccine in broiler chickens. For this study, 360 day-old broiler chicks were randomly assigned to six feeding trials, each with three replicates containing 20 chicks. The control group (T1) was only fed a basal diet alone, while the treatment groups were given the basal diet supplemented with 1% of basil (T2), lemongrass (T3), peppermint (T4), rosemary (T5), and thyme (T6) leaves powder, respectively. Body weight, feed intake, and feed conversion ratio were recorded. All chicks were vaccinated against IBD on days 7 and 19. A serology test was conducted to check the antibody titer against the IBD vaccine. The findings of this study showed that chickens in group T2 had significantly consumed more feed, followed by T1 and T6. During the overall study period, chickens in group T4 had significantly better feed conversion efficiency, followed by T3 and T6. Chickens in groups T5 and T6 showed a more pronounced antibody titer against the IBD vaccine at days 21 and 42 of the experiment. Therefore, these findings indicated that supplementation of basil leaf powder improved feed intake. Moreover, peppermint and lemongrass leaf powder improved the feed conversion ratio. In addition, supplementation of rosemary and thyme enhances the immune status of broiler chickens and could be considered a natural growth promoter feed additive. Therefore, further studies should be done to discover their beneficial effects to use as alternative feed additives in broiler chickens. Keywords: Body weight, Broiler chicken, Feed conversion, Feed intake, Immune response, Infectious bursa disease

Changes in antibody titres and comparative efficacy of some unconventional remedies in mitigating the effects of infectious bursal disease virus infection in pullet chicks

Unconventional remedies are used by farmers against infectious bursal disease (IBD). This study assessed changes in IBD antibody titres and efficacy of some unconventional remedies used by farmers against IBD. Day old ISA brown pullets were assigned into eight groups (A-H) and inoculated with a very virulent IBD virus (vvIBDV) at 21 days of age as follows; group A - administered aqueous leaf extract of Kaya senegalensis (KS); B, C, D, E, and F administered remedies designated as SEV, ENP, ASMS, DLP, and OVX, respectively; G, and H were negative, and positive control, respectively. Changes in IBD antibody (Ab) titres, clinical signs, morbidity and mortality rates, gross lesions, weights and organ ratios of bursal (BF), spleen (S) and thymus (T) were assessed. There were protective levels of Ab in groups of chicks at 2 and 7 days of age. SEV and ASMS potentiated Ab response to vvIBDV; SEV mitigated the severity of clinical signs, morbidity and mortality rates, gross lesions and changes in body and BF weights and SBR; KS clinical signs, morbidity and mortality rates, BF weight and BBR; ENP morbidity rate, spleen and thymus weights and TBR; ASMS thymus weight and TBR; DLP gross lesions, BF weight and BBR; OVX body, spleen weights and SBR. The remedies demonstrated varied actions against VVIBDV infection. SEV and KS leaves could be administered at the onset of IBD outbreak and before IBD vaccination. Processing of KS leaves to reduce concentration of antimetabolites is recommended.

Effects of Dietary Supplementation of Vitamin E on Growth Performance and Immune System of Broiler Chickens

As a potent antioxidant, Vitamin E may lessen the potentially harmful consequences of such oxidative stress to protect broilers against immune-pathological damage. Broiler chicken growth and viability are enhanced by Vitamin E supplementation. The present study aimed to investigate the effects of Vitamin E dietary supplementation on broiler chickens’ growth performance and health status. A total of 48 one-day-old Ross chicks were randomly divided into two groups of control and treatment (supplementation of Vitamin E at a dose of 300 mg/kg diet) with three replicates per group. The study included an equal number of Ross breed chicks and Vitamin E dosage in two trials on two different dates (January and March, 2022). In both trials, the obtained results indicated no significant changes in weight gain in the control and treatment groups. In both trials, there were no significant differences in the spleen weight of the control and treated groups; however, from day 1 to 28 of the second trial, the bursa of Fabricius was heavier in the treated group than in the control group. Additionally, Vitamin E had no significant effects on the mitogenic responses to phytohemagglutinin (PHA) and Concanavalin A (Con A). Dosages of 20 and 10 µl for both PHA and Con A did not significantly affect the rate of pure lymphocyte proliferation in chicks fed 300 mg Vitamin E /kg feed. Cell-mediated immunity did not differ significantly between the two trials. The percentages of CD4, CD8, Bu1, and MHCII molecules in the spleen and cecal tonsil of the chicks that received Vitamin E 300 mg/kg feed did not change significantly. The antibody titers against infectious bronchitis and infectious bursal disease vaccines showed no significant differences. On day 42, there was a trend toward an increase in antibody titer in the case of the Newcastle disease vaccine. In conclusion, 300 mg/kg of Vitamin E added to the diet did not improve growth performance and immunity in broiler chicks. Keywords: Broiler chicken, Growth performance, Immune system, Vitamin E

Combination Therapy for the Treatment of Shingles with an Immunostimulatory Vaccine Virus and Acyclovir.

Practically the entire global population is infected by herpesviruses that establish lifelong latency and can be reactivated. Alpha-herpesviruses, herpes simplex viruses 1 and 2 (HSV-1/HSV-2) and varicella zoster virus (VZV), establish latency in sensory neurons and then reactivate to infect epithelial cells in the mucosa or skin, resulting in a vesicular rash. Licensed antivirals inhibit virus replication, but do not affect latency. On reactivation, VZV causes herpes zoster, also known as shingles. The 76-year-old first author of this paper published an autobiography of his own severe herpes zoster ophthalmicus (HZO) infection with orbital edema, which is considered an emergency condition. Acyclovir (ACV) treatment was complemented with an immunostimulatory viral therapy, which resolved most symptoms within a few days. The orally administered live-attenuated infectious bursal disease vaccine virus (IBDV) delivers its double-stranded RNA (dsRNA) cargo to host cells and activates the natural antiviral interferon (IFN) gene defense system from within the host cells. IBDV has already been demonstrated to be safe and effective against five different families of viruses, hepatitis A virus (HAV), hepatitis B and C virus (HBV/HCV), severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and varicella zoster virus (VZV). Here we propose a short phase I/II trial in elderly shingles patients who will be assigned to receive either ACV monotherapy or ACV combined with R903/78, an attenuated immunostimulatory IBDV strain. The primary endpoints will be safety, but the efficacy of the combination therapy against the ACV monotherapy also will be assessed.

Seroprevalence and associated factors of infectious bursal disease (IBD) in indigenous chicken in eastern province in Rwanda

ABSTRACT The status of Infectious bursal disease (IBD) in indigenous chickens and backyard poultry in Rwanda has not been previously elucidated. This cross-sectional study was to determine the seroprevalence of infectious bursal disease in indigenous chickens and to identify the associated factors. The study was been done in three districts in the Eastern province of Rwanda where blood from 364 indigenous chickens were collected. ID Screen® IBD indirect enzyme-linked immunosorbent assay (ELISA) test was used to detect IBD antibodies in these birds. 145 questionnaires were also administered to poultry farmers to obtain information on biosecurity measures and associated factors to IBD outbreaks. The study revealed 48.4% (176/364) prevalence of the chicken with IBDV antibodies with statistical significance (P < .05) among/between location and age groups. The questionnaire revealed that there were other important associated factors which included chicken scavenging for seed as a source of food (59.3% of farmers reported), absence of routine vaccination (53.8%), live chickens are purchased from the open market with no information about IBD outbreaks and vaccination (30.0%), open disposal of dead chickens suspected of IBD (58.9%). IBD virus antibodies are present in indigenous chicken in Eastern Rwanda hence further investigation to better understand the epidemiology of IBD virus in indigenous chickens is desired and more research is needed to identify the role of indigenous chickens in the spread of IBD virus in Rwanda.

Efficacy of different live infectious bursal disease vaccines on antibodies to infectious bursal disease virus and Newcastle disease vaccine La Sota in ISA brown chicks

Aim: In this study, the efficacy of five commercial live infectious bursal disease (IBD) vaccines on antibody (Ab) decay and response to a very virulent IBD virus (vvIBDV) and Newcastle disease (ND) vaccine La Sota in ISA Brown chicks were assessed. Methods: Seven groups of chickens (A, B, C, D, E, F, and G) comprising 50 chicks each were used for the study. Groups A, B, C, D, and E were vaccinated with Bur-706, MB-Strain, B87-Strain, Bursa-B2K, and HIPRA live IBD vaccines, respectively, at 14 and 28 days of age (doa), and challenged with a vvIBDV at 35 doa. Groups F and G served as positive and negative controls, respectively. At 42 doa, all groups were vaccinated with ND vaccine La Sota. Blood was collected at 1, 7, 14, 21, 28, 35, 42, and 49 doa, and serum was harvested. The serum was analyzed for IBD virus (IBDV) Ab titres using enzyme-linked immunosorbent assay (ELISA) and ND Ab titres using a haemagglutination inhibition (HI) test. Results: Results revealed significantly (p &lt; 0.05) higher ELISA IBDV Ab titres in groups A to E than in F from 21 to 49 doa, with the highest in group D. At 49 doa, there was significantly (p &lt; 0.05) higher HI Ab titre in groups A to E than in F with the highest in group D. In conclusion, the live IBDV vaccines were immunogenic following vaccination. The vaccines decreased the decay of IBDV Ab and mitigated the decreased response to ND vaccine La Sota in the chicks following the vvIBDV challenge, with more effects induced by Bursa-B2K. Conclusion: The live vaccines (Bur-706, MB-Strain, B87-Strain, Bursa-B2K, and HIPRA) were immunogenic following vaccination.

DETECTION OF MATERNALLY DERIVED ANTIBODIES (MDA) TITER AND COMPARISON OF INTERMEDIATE AND INTERMEDIATE PLUS (GM-97 STRAIN) VACCINES OF INFECTIOUS BURSAL DISEASE VIRUS

The Infectious Bursal disease (IBD) is an important devastating disease among the infectious diseases of poultry in Bangladesh. Hence, this study was designed to determine the MDA titer and compare the two commercially available vaccines strains of IBDV (“GM-97 strain Intermediate plus” and “Intermediate type strain”). In this study, a total of 1500 layer birds were equally allocated into three groups (group-A, group-B and control). The Group-A and Group-B were vaccinated by “GM-97 strain Intermediate plus” and “Intermediate type strain” of IBD vaccine, respectively and control was unvaccinated. Blood samples were collected prior to vaccination (1- and 7-days old birds), as well as 7, 14, and 21 days after vaccination. The antibody titer was measured by iELISA test. The highest MDA mean titer was 6227.69±327.63 in day-old birds. The group-A birds had the significantly (p&lt;0.01) higher antibody mean titer than group-B and control. The highest antibody mean titer was 9121.94±657.05 at the age of 39 days in group-A. The MDA titer at 1 days-old had the higher effect size (4.10; CI:4675.36-6072.01; n=16). In group-A, the highest effect size (4.49, CI:5953.80-7556.08; n=16) was in 32 days-old (14 d.p.v.) and the group-B had the highest effect size (3.35; CI:4861.04-6702.59; n=16) was in 32 days-old (14 d.p.v.). Significantly (p&lt;0.01) higher histopathological-lesion scores were 4.75±0.25 and 3.5±0.65 in 32- and 39-days-old respectively in group-A. In brief, the protective level of IBDV MDA titer may remain up to 1 week of post-hatching and the Intermediate plus vaccine can generate higher antibody titer than the intermediate type.

Comparative Safety, Immunogenicity, and Efficacy of CEF Cell-Based and DF-1 Cell Line Adapted Infectious Bursal Disease Vaccines in Specific-Pathogen-Free Chickens.

Infectious bursal disease (IBD) is an immunosuppressive and economically important disease of young chickens caused by infectious bursal disease virus (IBDV). The National Veterinary Institute (Bishoftu, Ethiopia) produces intermediate IBDV vaccine using primary chicken embryo fibroblast (CEF) cells, a method with technical and economical cumbersome. This study assessed the safety, immunogenicity, and efficacy of DF-1 cell line-adapted IBDV LC–75 vaccine strain in reference to the CEF-based vaccine. Confluent monolayer of DF-1 cells was infected with IBDV and cells with cytopathic effects were passaged until 3rd passage. Viral growth was confirmed using a one-step RT-PCR targeting IBDV VP2 gene. Viral titer increased from 1st passage through 3rd passage. Safety was assessed in 30 specific-pathogen-free chickens (15 chickens/group) injected with 10-fold field dose of each vaccine intraocularly and monitored for 21 days. For immunogenicity and efficacy, 60 specific-pathogen-free chickens were grouped into 3 (20 chickens/group). First and 2nd group received DF-1 cell and CEF-based IBDV vaccines, respectively. The 3rd group served as unvaccinated control. Antibody response was measured using iELISA. Chickens were challenged 4 weeks postvaccination with very virulent IBDV (vvIBDV) intraocularly and followed-up for 10 days. Vaccination did not cause any adverse reactions during the 21 days of follow-up. In addition, both vaccines induced higher antibody titer 14 and 24 days-post-vaccination as compared to unvaccinated controls (p < 0.05). Moreover, DF-1 and CEF-based IBDV LC–75 vaccines rendered a complete protection against vvIBDV. Contrarily, morbidity and mortality in unvaccinated chickens was 50% and 30%, respectively. The results indicated that DF-1 and CEF cell-based IBDV vaccines are comparably immunogenic and efficacious. Therefore, DF-1 cell-line can be considered an affordable and convenient alternative to the CEF-based approach. The suitability of DF-1 cells to grow other IBDV strains and safety of these vaccines on bursa of Fabricius should further be investigated.

Efficacy of immune complex infectious bursal disease vaccines against very virulent infectious bursal disease virus challenge in commercial layer chicken

Efficacy of immune complex infectious bursal disease vaccines against very virulent infectious bursal disease virus challenge in commercial layer chicken

Histopathological evaluation of the effects of live Infectious bursal disease vaccine originated from WF2512 strain on bursa Fabricius in the broilers

Infectious bursal disease (IBD) is a viral disease that causes significant economic losses in young chickens, characterized by lymphoid depletion and inflammation in the bursa Fabricius (BF). The incidence of the disease shows an increasing trend all over the world. Active and passive immunization is very important as well as strict hygiene measures in combating outbreaks. However, the fact that live-attenuated vaccines (mild, intermediate, hot) used for this purpose cause immunosuppression because of bursal damage is seen as an important limitation. In this study, it was aimed to histopathologically investigate the effects of commercial IBD vaccines originating from WF2512 (intermediate plus/hot, orally with drinking water) on BF under routine broiler rearing conditions. For this, BFs of 55 Ross 308 hybrid breed chickens (50 test, 5 controls) from five different broiler farms were used. In addition to standard vaccines, the IBD vaccine was given on day 15, and five samples from each farm were obtained 10 days later (25th day). After the first sampling, the second BF sampling was performed at the age of 38 days. Histopathological bursal lesion score was applied to evaluate the effectiveness of the vaccine. Accordingly, it was determined that the bursal lesion score, which increased slightly to moderately in the first samples, decreased in the second samples (27-61%). This was accepted as an indication that the bursal damage, which increased with IBD vaccine administration, diminishes over time and that histological regeneration was increased.

Immunopathological comparison of in ovo and post-hatch vaccination techniques for infectious bursal disease vaccine in layer chicks.

This study was designed to compare immunopathological effects of in ovo vaccination with post-hatch vaccination against IBD in White Leghorn chicks. A total of 189 embryonated eggs were divided into six groups. At day 18 of incubation, groups A–C were administered in ovo with 228E, Winterfield 2512:10/3 and 2512/90:10/2.7, respectively, group D (post-hatch vaccination) and group E as shamed control (for quality evaluation of in ovo vaccination technique), and group F as control. The results showed that antibody titers against IBD detected by ELISA on days 2, 17, and 28 were significantly higher in all in ovo groups as compared to control groups E and F. On day 17, all vaccinated groups (in ovo and post-hatch vaccinated) showed no significant differences in antibody titers among themselves; however, at day 28, only the post-hatch group showed significantly higher antibody titers followed by in ovo vaccinated groups. The cell-mediated immunity determined by PHA-P assay was significantly higher in all vaccinated groups than the non-vaccinated groups. No clinical signs of IBD infection were observed in any of the vaccinated groups. There was only increase in bursa size of groups vaccinated with intermediate plus strains (groups A, C, and D) at day 28. The histopathology showed that all the treatment groups had mild lesions induced by IBD virus in bursa. This study concluded that in ovo vaccination with live IBD vaccines provides protective immunity to the chickens even in the presence of IBD-specific MDA; therefore, the onset of immunity was much earlier than the post-hatch vaccination and in ovo groups also maintained protective immunity against IBD for longer time.

Review of Diagnostic and Vaccination Approaches of Infectious Bursal Disease of Poultry

Infectious bursal disease, also known as Gumboro disease, is a highly contagious and acute viral disease of poultry characterised by the destruction of lymphoid cells. Diagnosis of infectious bursal disease involves consideration of the flocks’ history, clinical signs, and lesions. The objectives of this paper are to highlight various commonly used diagnostic methods for infectious bursal disease and to review advances made in diagnostic methods and vaccination strategies for infectious bursal disease, with special emphasis on the strengths and weaknesses of each of those techniques. Isolation of infectious bursal disease virus followed by its serological assay and histopathological examination of the bursa is regarded as the gold standard method of infectious bursal disease diagnosis. Serological tests such as agar gel, immune diffusion, enzyme-linked immuno sorbent assay, and viral neutralisation tests are commonly used laboratory assays in diagnosing infectious bursal disease viruses. Recently, the most accurate and relatively fast diagnostic method, the molecular technique, is widely used. The molecular diagnostic technique is the simplest and most sensitive of the diagnostic techniques reviewed. The virus causes immunosuppression, so the infected chicken recovers from the acute disease but becomes more susceptible to infections by other pathogens. Therefore, prevention is important and vaccination has become the principal control measure of infectious bursal disease virus infection in chickens. Conventional attenuated live and killed vaccines are the most commonly used vaccines. With the advancement of knowledge and technology, new generation or genetically-engineered vaccines like deoxyribonucleic acid and subunit vaccines have been used. Various vaccination strategies, such as in ovo, at hatch, and post hatch vaccination, are used. Hatchery vaccination is becoming a common practice. Based on this review paper, more affordable and effective infectious bursal disease vaccines that are affordable and readily available must be identified with further cost-benefit analysis.

The First Occurrence of Hepatitis-Hydropericardium Syndrome in Iran and Effective Applied Control Measures in the Affected Commercial Broiler Flock.

Fowl adenoviruses cause three economically important diseases in broiler chicken flocks: hepatitis-hydropericardium syndrome (HHS), inclusion body hepatitis (IBH), and adenoviral gizzard erosion. IBH has not been considered a serious threat in northeast Iran since the last decade, because no major effect on flock performance has been noticed along with a low mortality rate. During this period, all the sporadic IBH outbreaks have also been investigated for HHS without finding any confirmed case. In March 2021, a 15-day-old commercial broiler flock in northeast Iran showed a 50% mortality rate, and birds underwent postmortem examination, histopathology, molecular testing, and phylogenetic analysis for possible disease agents. Typical gross lesions of HHS were observed postmortem that included hydropericardium with an unusual accumulation of jelly-like and straw-colored fluid in the pericardial sac (without right ventricular failure); petechial or ecchymotic hemorrhages on the myocardium, myocardial valves, and endocardium; and discolored and mottled liver along with small white foci and petechial or ecchymotic hemorrhages. Histopathologic analysis showed necrosis of hepatocytes and basophilic inclusion bodies in the livers. The molecular tests performed for detection of fowl adenovirus (FAdV), H5 avian influenza virus, Newcastle disease virus, avian infectious bronchitis virus (IBV), H9N2, chicken infectious anemia virus (CIAV), infectious bursal disease (IBD) virus, Marek's disease virus, Ornithobacterium rhinotracheale, Mycoplasma gallisepticum, and Mycoplasma synoviae turned out positive for FAdV, CIAV, IBD vaccine virus, and IBV serotypes 793B and variant I. The phylogenetic tree based on the hexon gene loop 1 demonstrated a FAdV serotype 4 (FAdV-4) that was identical to Pakistani isolate PARC-1/98. Because it was the first detection of a FAdV-4 in Iran, the stamping out program was applied immediately on the basis of HHS gross lesions and positive PCR reaction on pericardial jelly-like fluid. It seems that this eradication strategy was successful because no outbreaks were noticed for 2 mo after the initial outbreak. It was concluded that the use of gross pathologic baselines, quick diagnosis of disease, and close collaboration between governmental and private sectors were the critical factors that helped locally control the first occurrence of HHS in Iran.