Evaluation of the effect of live LaSota Newcastle disease virus vaccine as primary immunization on immune development in broilers
| Autor: | John B. Carey, J C S Martinez, Wen-Ko Chou, Luc Berghman |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
0301 basic medicine
040301 veterinary sciences Newcastle Disease animal diseases Newcastle disease virus Vaccines Attenuated Newcastle disease Virus 0403 veterinary science Random Allocation 03 medical and health sciences Immune system Animals Poultry Diseases biology 04 agricultural and veterinary sciences General Medicine biochemical phenomena metabolism and nutrition Acquired immune system biology.organism_classification Virology Vaccination Titer 030104 developmental biology Immunization Influenza Vaccines biology.protein Animal Science and Zoology Antibody Chickens Immunity Maternally-Acquired |
| Zdroj: | Poultry Science. 97:455-462 |
| ISSN: | 0032-5791 |
| DOI: | 10.3382/ps/pex339 |
| Popis: | Newcastle disease remains a major concern to the poultry industry; however, it can be managed with effective vaccination programs. The main objective of this study was to evaluate the effect of 2 1× doses of live LaSota strain Newcastle disease virus (NDV) vaccine administered oculo-nasally on d one and 21 on development of humoral and cell-mediated immune response in broilers, and to compare different immunization schedules. Two experiments were conducted. In Experiment I (n = 320), Ross 308 birds were randomly assigned to an unvaccinated control group or vaccinated treatment. [Both treatments consisted of 4 pens per treatment and 40 birds per pen]. At d one, live NDV LaSota strain vaccine was used as a primary immunization to evaluate its impact on adaptive immunity. No substantial NDV-specific humoral immune response was established. Body weights were significantly higher (P < 0.05) in the vaccinated birds on d 4 and 7. Spleen index of the vaccinated birds was significantly (P < 0.05) lower at d 28 and 35. Flow cytometry showed reduced levels of peripheral and splenic B and T lymphocytes. Interferon gamma secreted by splenocytes and in circulation was measured; the results showed a reduced expression post-secondary immunization. In Experiment II (n = 180), the role of maternal antibodies and primary vaccination at d one was evaluated using 3 vaccination protocols. Protocol 1 used live B1 strain as primary immunization, whereas protocol 2 used live LaSota strain. Protocol 3 used live LaSota strain after maternal antibodies had decayed. Protocol 3 resulted in the highest NDV-titer level during the trial. Protocol 2 had the lowest NDV titer. Feed conversion was significantly higher (P < 0.05) in protocol 3 compared to 1 and 2. Overall, the results indicate that the use of live LaSota strain NDV vaccine as primary immunization at d one has a detrimental effect on the development of adaptive immunity in broilers; however, its use after the level of maternal antibodies decays results in a robust antigen-specific humoral immune response. |
| Databáze: | OpenAIRE |
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