EFFECTIVENESS OF SINGLE AND DOUBLE RECOMBINANT HERPES VIRUS OF TURKEY VECTORED VACCINES BOOSTERED WITH LIVE ND VACCINE AGAINST THE HIGHLY PATHOGENIC NEWCASTLE DISEASE VIRUS GENOTYPE VII | ||||
| Assiut Veterinary Medical Journal | ||||
| Volume 71, Issue 185, April 2025, Page 463-481 PDF (2.7 MB) | ||||
| Document Type: Case report | ||||
| DOI: 10.21608/avmj.2025.336643.1477 | ||||
 View on SCiNiTO | ||||
| Authors | ||||
A. S. HAMZA  1; E. M. ELBORAAY1; H. F. ATTIA2; A. M. HELAL3
| ||||
| 1Avian and Rabbit Diseases Department, Faculty of Veterinary Medicine, Benha University, Moshtohor 13736, Qalyubia, Egypt | ||||
| 2Histology Department, Faculty of Veterinary Medicine, Benha University, Egypt | ||||
| 3Central Laboratory for Evaluation of Veterinary Biologics. Agriculture Research Centre | ||||
| Abstract | ||||
| This study assesses the effectiveness of recombinant Newcastle disease vaccine formulations in one-day-old specific pathogen-free (SPF) chicks, with an emphasis on their performance against the current circulating NDV strain (Egypt-NDV-RLQP-2021) in Egypt. A total of 100 SPF chicks were divided into five groups; Group 1 received INNOVAX-ND-IBD®, Group 2 was given Vaxxitek ® HVT + IBD + ND, and Group 3 was vaccinated by Vectormune® ND, which utilized the herpesvirus of turkeys (HVT) as a vector by integrating the fusion (F) gene from Newcastle disease virus (NDV) into the HVT genome. Vaccinated groups received a single dose of live clone NDV genotype II vaccine at 15 days of age via intraocular instillation. Group 4 was kept as the positive control (no vaccination, challenged with NDV), and Group 5 was the negative control. Groups 1, 2, 3, and 4 were challenged 28 days later with virulent NDV genotype 7 with 0.2 mL 106 EID50 of a challenge virus intramuscularly. Chicks were monitored for clinical signs, mortality, and viral shedding using real-time PCR. Histopathological findings proved that all vaccinated groups showed good control in masking and preventing lesions compared to the positive control group 4. Serology examinations indicated a significant increase in antibody titer post-vaccination and challenge in all vaccinated groups, giving a protective immunity against NDV. For viral shedding, Group 2 showed no detectable virus at any time, which means superior control for viral shedding. In conclusion, our study highly recommends HVT-based vaccines together with NDV live vaccines, as they exhibited full clinical protection against NDV genotype VII. | ||||
| Keywords | ||||
| Newcastle; Vector vaccine; Genotype VII; SPF chicks | ||||
|
Statistics Article View: 212 PDF Download: 98 |
||||
