Protection Effect of Vaxxitek HVT + IBD Vaccine Against Infectious Bursal Disease in Broiler Chickens

Abstract

The very virulent infectious bursal disease virus (vvIBDV) infection cause constant and frequent outbreaks of IBD. In order to prevent the disease caused by vvIBDV, moderate-virulent live vaccines are usually used in broilers, but these vaccine influence the immune system of chickens and cause the immunosuppression. VAXXITEK ® HVT+IBD bivalent vaccine, a novel vaccine produced by Merial Company, is the recombinant vaccine generated by inserting IBDV VP2 gene into the HVT genome. The recombinant vaccine could prevent Marek's disease and IBD of chickens at the same time after vaccinated by the subcutaneous route at 1-dayold. The objective of this study was to evaluate protection effect of this new vaccine against IBD in broilers. The results of the lab and field immunization trial showed that the vaccination of VAXXITEK ® HVT+IBD vaccine did not damage the bursa of broilers; the level of IBD antibody of the VAXXITEK ® HVT+IBD vaccination groups was higher than IBD-BLEN ® vaccination groups at 21-day-old; the protection effect of the VAXXITEK ® HVT + IBD vaccination groups was better than IBD-BLEN ® vaccination groups, especially at 21-28 day. The results indicated that VAXXITEK ® HVT + IBD vaccine could provide better protection to broiler chickens against IBD.

Comparative Evaluation of HVT-IBD Vector, Immune Complex, and Live IBD Vaccines against vvIBDV in Commercial Broiler Chickens with High Maternally Derived Antibodies

“…Similarly, group A had the lowest histopathological lesion score of bursa post challenge. All of these reflect the superiority of the vaccine used in this group in protection against the vvIBDV challenge; similar findings were reported by Le Gros et al [42], Sultan et al [54], and Rashid [55].…”

“…Independence of FCR was recorded in all groups during the challenge period (seven days); groups A and B showed the best FCR and similar results were described by Rashid [55].…”

“…Nevertheless, the use of killed IBD vaccine at five days of age with two doses of intermediate D78 provoked significant immune response beginning from 21 days of age more than two doses of live vaccine on group D. It may be attributed to the fact that killed vaccines are more immunogenic, inducing humoral immunity that may neutralize part of the virus replication and improve clinical protection confirming the results of Sultan [54] that chicks need to receive live and killed vaccines to induce an immediate immune response and to maintain the high antibody titers. Moreover, Rashid [55] mentioned that killed vaccines have been used occasionally in chicks as young as 10 days old to overcome virulent viruses.…”

Selected aspects of infectious bursal disease – the current state of knowledge

“…Szczepionka może być podana in ovo (na 3 dni przed wylęgiem) lub podskórnie w pierwszej dobie życia, w obecności nawet wysokich mian przeciwciał matczynych. Badania wykazały, że szczepionka nie powoduje zmian w bursie Fabrycjusza, a co za tym idzie -immunosupresji (12,86). Zakażenie kontrolne immunizowanych szczepionką wektorową kurcząt SPF wykazało, że zapewnia ona protekcję sięgającą 95-100% przed wirusami o różnej zjadliwości (vvIBDV, cIBDV, vIBDV pochodzące ze Stanów Zjednoczonych) (12).…”

Efficacy of recombinant VAXXITEK HVT-IBDv vaccine against very virulent Infectious bursal disease virus (vvIBDv) challenge in layer chicks: A pilot study

“…However, in experiments presented here, 2 out of 10 birds in groups G3 and G4 had symptoms of acute IBD, and had succumbed to the infection It has been established recently that even in the presence of high titers of maternal antibodies, the recombinant vaccine (vHVT13) was efficiently protecting chicks against classical, very virulent and variant IBDv (Bublot et al, 2007, Perozo et al, 2009, Prandini et al, 2016. A few experiments with the rHVT-IBDv have been done in commercial broilers and a good antibody response to IBDv was obtained in the research work conducted in Italy (Le Gros et al, 2009), Slovenia (Zorman-Rojs et al, 2011 and Jhenaidha (Rashid et al, 2013) after a subcutaneous application and when the in ovo vaccine delivery system was used (Roh et al, 2016). It was also shown that the recombinant VAXXITEK HVT-IBDv vaccine provided a high maternal antibody titer in progeny from parents vaccinated with a single recombinant vaccine or if the rHVT-IBDv vaccine was combined with the inactivated vaccine, compared to a single inactivated vaccine.…”