The Reason Analyses Of Mycoplasma Synoviae Infection In A Egg Breeding Farm

Mycoplasma synoviae disease is an infectious disease and do great harm to the healthy and growth of chicken flocks, which was caused by Mycoplasma synoviae(Mycoplasma synoviae,MS). Infected chickens shown joint swelling, synovial capsule and tendon inflammation and swelling of solid organs.Once MS circulate among chicken flocks, It can cause them growth retardation, high eliminated percentage and great loss of chicken’s meat quality and egg’s production.Furthermore, the MS prone to cause cross-infection with other pathogens; It can enhence the virulence of pathogen and increase mortality.At present, the study of MD is few at home and abroad. In China, the results of serological investigation of MS were positive in Hena, Beijing, and Shaanxi province, where the MS isolates were obtained. Taken together with the previous study, in order to further research the reason analyses of Mycoplasma synoviae infection in a egg breeding farm whether environment factors or vertical transmission, this study enlarged the field of investigation and detected the infection condition of different generation and days of chicken flock.Meanwhile, the commercial chickens were grouped according to the maternal antibody titer and reared in isolator to study the route of transmission of MS in filial generation of chicken flocks, and observe the protective function of high maternal antibody on the filial generation.The main results of this research study as follows:1. The 35 week-old progenitor chicken is in a susceptible state,which were identified by sampling survey. The pathogens can be detected in the tracheal swab samples. The positive ratio of serological antibody is 70%.2. Hatching eggs and 1 day-old chickens were not detected pathogens during the sampling survey process.,1 day-old chicks have a high level of maternal antibody due to progenitor chicken flocks infected by MS. However,,pathogen could be detected in tracheal swabs of 35-week-old chickens, Furthermore, the positive ratio of serological antibody up to100%, The research results indicate that the progenitor chicken flocks were in a state of not infected by MS pathogens before of the attenuation end of maternal antibody, but after that state them were in a state of infected.3. The commercial chicken flocks grouped by the maternal antibody titer of MS pathogens, and reared in separate isolator. The results shown that there are many low vigor chicks and 1/3 of them have clinical symptoms of splits in low antibody group. In high antibody group, total chicks have high vigor. There were no significant difference betweentwo groups after one week.The positive ratio of serological antibody of 1 day-old chicken was100 % in high antibody group, which it become negative till 4 weeks and the negative results last until tenth weeks.The antibody positive rate The positive ratio of serological antibody of 1day-old chicken was 36% in low antibody group, which it become negative till 2 weeks and the negative results last until eleventh weeks..Compared with the previous experiment, the variance tendency of the antibody titer in this study not increased. Meanwhile, the detective results of PCR of MS pathogen in tracheal swab were negative till tenth week. The vertical transmission of MS has no impact on the filial generation in the state of no clinical symptoms of infected chicken. The infected filial generation mainly transmitted by some surrounding environment factors.