Epidemiological Investigation on Avian Infectious Laryngotracheitis in Some Regions of China from 2020 to 2022
In order to investigate the epidemiological characteristics of avian infectious laryngotracheitis(ILT)in some regions of China,from 2020 to 2022,47 210 samples suspected of being infected with avian infectious laryngotracheitis virus(ILTV)collected from some farms(households)in 29 provinces(municipalities)including Anhui,Beijing,Fujian,etc.,were detected by PCR,based on the results,statistical analysis of spatial,temporal and intergroup distribution was conducted.The results showed that 413 ILTV positive samples were detected,with a positive detection rate of 0.87%;the positive detection rates were 1.41%,0.72%and 0.56%,respectively from 2020 to 2022;ILTV was detected out in samples of every month,especially in the period from October to next May;ILTV positive samples were found in most provinces,with high positive rate in the provinces with intensive chicken production;all the 4 varieties of chickens were susceptible,but the positive rates of yellow-feathered chickens(1.56%)and laying hens(1.11%)were higher,so were the chicken flocks aged＞3 to 9 and＞18 to 24 weeks.In conclusion,ILTV was widely prevalent in chicken flocks in China,with decreasing positive detection rate year by year.The factors of low temperature season and early weeks of age contributed to a high infection risk of chicken flocks.It was recommended to improve the management of chicken flocks,and continue to conduct ILT epidemiological surveillance,with a view to laying a foundation for the adjustment of ILT prevention and control strategies and for the development of new vaccines.
万方数据
