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bioRxiv · 10.1101/2022.11.25.517975

Preparation of inactivated whole culture vaccine composed of Pasteurella multocida, Avibacterium paragallinarum, and Ornithobacterium rhinotracheale and evaluation of its protective efficacy in chickens

Abstract

Poultry, mainly chickens and its white meat represents one of the main, nutritionally valuable, and affordable red meat replacer source of protein throughout the whole world with special reference to developing countries. A long list of microbial agents especially bacterial pathogens threat chickens production cycles. They constitute one of the major problems facing the rapidly expanding poultry industry and are responsible for considerable economic losses.). Fowl Cholera, Infectious Coryza, and Ornithobacterium Rhinotracheale (ORT) diseases were among the serious bacterial infections that affect respiratory tract of chickens with an global adverse effect on poultry production. A formalized whole culture vaccine of composed of P. multocida serotypes A5, A8, A9 and D2, Avibacterium paragallinarum serotype A and C and Ornithobacterium rhinotracheale serotype A was prepared. This polyvalent vaccine proved to be safe producing no adverse side effects when injected in chickens. The immunizing efficacy of this vaccine was evaluated in SPF chickens, which were immunized at 6 weeks of age. The protective efficacy of the vaccine was determined using challenge test. The developed vaccine was effective in protecting chickens against Fowl Cholera, Infectious Coryza and Ornithobacterium Infection (ORT diseases) in chickens against challenge with these pathogens. Vaccinated chickens challenged with virulent Pasteurella Multocida serotypes A5, A8, A9 and D2 showed protection rates of 86.6%, 93.3%, 93.3% and 93.3%, respectively, as compared with 100% mortality in the non-vaccinated control. Vaccinated chickens challenged with Avibacterium paragallinarum serotypes A and C showed protection rates of 86.6% and 93.3%, respectively. Also, the protection rate against challenge with virulent Ornithobacterium rhinotracheale serotype A reached to 96.6%.

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BibTeXRIS

Roshdy, S., Soliman, R., Aly, M., Omar, L., Samir, A., Abo-Elyazeed, H., Aboul-Ella, H.. 2022-11-25. Preparation of inactivated whole culture vaccine composed of Pasteurella multocida, Avibacterium paragallinarum, and Ornithobacterium rhinotracheale and evaluation of its protective efficacy in chickens. https://doi.org/10.1101/2022.11.25.517975

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