DOI number:10.19958/j.cnki.cn31-2031/s.202108
Affiliation of Author(s):Yangzhou University
Journal:Chinese Journal of Animal Infectious Diseases
Key Words:Mycoplasma synoviae; maternal antibody; live attenuated vaccine; immune efficacy
Abstract:In this study, commercial laying hens with high levels of maternally - drived antibody (MAD) against Mycoplasma synoviae (MS) were used as experimental animals to evaluate the effect of MAD on the immune efficacy of MS attenuated live vaccine. The live MS vaccine (MS-H strain) was administered at 7, 14, 21 and 28 days of age, respectively. Choanal cleft swabs were collected weekly, and the genomic copy number of MS-H vaccine strain was evaluated by real-time quantitative PCR (qPCR) to evaluate the colonization of vaccine strain in vivo. At the time of 5 weeks after the last vaccination, all chickens were challenged with virulent MS strain and continuously observed until 4w post challenge, and the genomic copy number of virulent MS strain was evaluated by qPCR to evaluate the competition effect of live vaccine against challenge of virulent strain. Finally, all chickens were culled and autopsied, and the characteristic lesions were observed and recorded. The results showed that the level of MS-specific MDA decreased to negative level at 3 weeks of age, and the early high MDA level had a certain influence on the colonization of vaccine strains. However, the vaccine strains could be colonized effectively in different immunization groups vaccinated at different time, and the protective effect on the challenge of virulent strains was not significant influenced. The results of this study have important reference significance for guiding the preparation of the immunization procedure of MS live vaccine in the production.
Co-author:Min Cheng,Jixin He,Yang Chen,Mengyao Chen,Yongzhong Cao,Yantao Wu
First Author:Cuiwei Zhong
Indexed by:Research Atricle
Correspondence Author:Xiaorong Zhang
Discipline:Agricultural science
First-Level Discipline:Veterinary Medicine
Document Type:J
ISSN No.:1674-6422
Translation or Not:no
CN No.:31-2031/S
Date of Publication:2021-08-25