鸡传染性喉气管炎

herpesvirus leads to formation of type A intranuclear inclusion bodies
during first days of infection in tracheal epithelial cells and occasionally in conjunctival epithelium (diagnostically important) A型核内包含体
入侵门户：上 呼吸道和结膜
portals of entry: upper respiratory tract
and conjunctiva
神经性迁移到 三叉神经节 主要潜伏位置
virus replication in trachea, larynx
病毒在气管、 喉头复制
Stress 应激
neural migration to trigeminal ganglia main site of latency
细胞免疫应答
principal mediator of ILT resistance
ILT抵抗力的主要调节者
maternal antibodies
母源抗体
do not confer protection against infection or interfere with vaccination
不产生抗感染的保护，也不干扰疫苗接种
污染的设备、动物、人员、饲料、水
exsudates from nares, trachea conjunctiva are spread by air 来自鼻孔、气管和结膜的排出物，通过空气传播
Dies quickly in the environment
在环境中很快死亡
Birds that recover from ILT may be carriers of the virus for a prolonged period of up to two years ILT 发病康复鸡可以携带病 毒长达2年
production 由于严重爆发的形式，引起鸡死亡和/或产蛋减少，会导
Байду номын сангаас
致严重的生产损失，有经济重要性
Jones, 2001
Etiology 病因学
ILT is caused by a herpesvirus
ILT由疱疹病毒引起
Family:
Herpesviridae
Subfamily: Alphaherpesvirinae
males and heavier breeds are more susceptible 公鸡和较重型品种更易感
usually well controlled in layers by vaccination 通过接种疫苗，通常能够在蛋鸡进行很好的控制
within developed countries ILT virus has tended to persist as endemic infection in backyard and fancier chicken flocks
Infectious Laryngotracheitis 鸡传染性喉气管炎
Dr. Karsten Augustinski LAH, Cuxhaven
China, March 2009 罗曼动物保健，库克汉文
中国 . 2009年3月
Definition 定义
Infectious Laryngotracheitis (ILT) is a viral infection of the respiratory tract of chickens 鸡传染性喉气管炎（ILT）是鸡呼吸道的一种病毒感染。
Clinical findings 临床所见
severity of the disease varies with virulence of the virus
field strain and the resistance of the bird 疾病的严重性，随着感染毒株的毒力和感染鸡只的抵抗
性而变化
疱疹病毒科
α-疱疹病毒亚科
Species: Gallid herpesvirus 1 禽疱疹病毒1型
(syn.: Infectious Laryngotracheitis Virus)
（
命名为：传染性喉气管炎病毒）
herpesviruses are enveloped DNA-viruses 疱疹病毒是有囊膜的DNA病毒
在发达国家，ILT病毒已经趣向于以庭院和观赏鸡群地 方流行性感染的形式而持续存在
Pathogenesis I 致病机理 I
sources of infection
感染来源
acutely infected birds
急性感染鸡
carrier birds
携带病毒的鸡
contaminated equipment, animals, personnel, feed, water
mild form
温和型
in ILT virus infections of low pathogenic strains
conjunctivitis, watery eyes, nasal discharge, swollen
infraorbital sinuses, lowered egg production ILT病毒低致病性毒株感染，可见： 结膜炎、眼流泪、鼻有分泌物、眶下窦肿胀、产蛋下降
ILT: Herpesvirus 传染性喉气管炎：疱疹病毒
Epidemiology 流行病学
all ages of fowl are susceptible, most characteristic signs are seen in adult birds
所有年龄的鸡都易感，最为特征性的症状见于成年鸡
pheasants and peafowl can be affected through contact with chickens 雉鸡和孔雀可以通过与鸡接触感染
ILT is recognized worldwide
ILT被认为在全球广泛存在
serious outbreaks occur when ILT virus spreads from persistently
clinically inapparent persistent infection 临床不明显的持续感染
感染后6-12天 临床疾病
clinical disease 6-12 days pi
Stress
应激
Death Recovery 康复
死亡
Immunity 免疫力
Excretion 排毒
Spread of the disease
♦ they are not the primary mechanisms of protection
它们不是主要的保护机制
♦ there is generally a poor correlation between serum antibody titers and immune status of the flock
通常鸡群的血清抗体和免疫状态之间的相关性差
♦ mucosal antibodies are not essential in preventing replication in the trachea
粘膜抗体在防止病毒在气管中复制方面不是必要的
Immunity II 免疫力II
cell mediated immune response
感染后5-7天，可检测到病毒中和抗体，大约感染后21 天达到高峰，可以持续1年
♦ mucosal antibodies (IgA, IgG) which are capable of binding ILTV become detectable from 7 days p.i.
能够粘附ILT病毒的粘膜抗体（IgA，IgG），感染后7天 即可检测到
Can survive up to 100 days if protected by organic material
若有有机物的保护， 病毒可存活达100天
Pathogenesis II 致病机理II
The virus kills the cells lining the airways, resulting in variable degrees of inflammation and breathing difficulties
following the stress of re-housing and the onset of reproduction. 潜伏感染鸡在转群和开产应激后再次排毒
usually associated with a break down in bio-security;
movement of personnel, dead bird disposal, manure
disposal, exchanging farm equipment etc. 通常与生物安全漏洞有关；人员移动、死鸡处理、粪便
处理、鸡场设备交换等
incubation time is from 6 – 12 days, within a flock ILT
spreads rather slowly within a few days. 潜伏期为6-12天，在群内，ILT的传播要慢几天
infected flocks to non-vaccinated animals 在ILT病毒从持续感染鸡群传播给非免疫鸡群时，严重爆发才发生
severe forms are of economic importance since they may result in
severe production losses due to mortality and/or decreased egg
replicate in the nucleus of the host cell 在宿主细胞核内复制
there is one serotype and strains appear to be antigenically homogeneous 只存在1个血清型，不同毒株的抗原性一致。疱疹病毒导致
疾病的传播
natural route of infection is by way of the respiratory tract
and ocular route (eyes).
自然感染途径是经呼吸道和眼
the latent carrier usually defined as recovered birds or
vaccinated chickens become carriers and can shed the virus for long periods of time. 潜伏携带者通常被限制， 因为康复鸡或疫苗接种鸡会成为携带者并长时间地排毒
re-excretion of ILT virus from latently infected chicks
herpesviruses lead to persistant infection of the host 宿主的持续感染
naturally occuring ILT virus strains vary in virulence from highly virulent
strains to strains of low virulence 自然存在的ILT病毒株，有高毒力到低毒力的不同。
Immunity I 免疫力I
humoral immune response
体液免疫应答
♦ virus-neutralizing antibodies are detectable 5 - 7 days after infection, peak around 21 days p.i., may persist for a year
病毒破坏呼吸道细胞，导致不同程 度的感染和呼吸困难
Transmission through the egg is not known 经蛋传递未知
Newly hatched chicks are free from infection!
新出壳小 鸡无感染
Pathogenesis III 致病机理III