Immunological Study on Chickens Vaccinated with a Trivalent Combined Inactivated Mycoplasma gallisepticum, Escherichia coli, and Newcastle Disease Virus (ND) Vaccine

Vaccination is a key control measure for most avian diseases, including the endemic Newcastle disease (ND), Mycoplasmosis, and Colibacillosis in Egypt. This study evaluated three inactivated monovalent commercial vaccines, one for each infection, and an inactivated trivalent locally prepared vaccine for the same diseases. The evaluation included challenge tests for the three diseases and monitoring of antibody levels using the hemagglutination inhibition test for ND and Enzyme-Linked Immunosorbent Assay (ELISA) for Mycoplasmosis. The trivalent vaccine showed protective percentages of 100%, 80%, and 80% against the three diseases, respectively. The monovalent commercial vaccines provided protections of 100%, 70%, and 70%, respectively. Hemagglutinating antibody titers for the trivalent vaccine were 6.9 and 6.5 log 2 at the second-week post-vaccination for LaSota and GVII antigens, respectively. In comparison, the monovalent commercial vaccine showed 4 log 2 at the first-week post-vaccination for LaSota antigen and 6.7 log 2 at the second-week post-vaccination for GVII antigen. The ELISA antibody titers for Mycoplasmosis in both trivalent and monovalent vaccines increased gradually from the first-week post-vaccination (1043 and 987) to peak at the seventh-week post-vaccination (2266 and 2226), respectively. In conclusion, the inactivated trivalent vaccine against ND, Mycoplasmosis, and Colibacillosis demonstrated high potency, efficacy, and safety.   Cite this article as: Omar, D. M., Gadallah, F. M., Abdrabo, M. A., Gamal, F. E., Monir, N. M., Gamil, M. A. , Abdel Rahman, M. A. A., Marden, N. A., Abu Zaid, R. A., Abd El-Aziz, H. M. G., Khedr, A. A., & Omar, L. M. (2025). Immunological study on chickens vaccinated with a trivalent combined inactivated Mycoplasma gallisepticum, Escherichia coli, and newcastle disease virus (ND) vaccine. Acta Veterinaria Eurasia, 2025, 51, 0014, doi: 10.5152/actavet.2025.25014.