Identification of A Field Strain of Infectious Laryngotracheitis Virus Isolated from Jiangsu Province

[ Objective] To isolate and identify infectious laryngotracheitis virus （ILTV） from chickens. [ Method] Larynx, trachea, liver and other organs were collected from infectious laryngotracheitis （ILT）-suspected layers. And ILTV TK gene was amplified from these specimens by PCR for initial diagnosis. Virus fluid was isolated and inoculated into SPF chicken embryos via allantoic cavity and chorioallantoic membrane （CAM）, respectively. Hyaluronic acid in allantoic fluid was detected, and CAM lesions were observed. The definite diagnosis was performed through animal regression test. [Result] A 1.3 kbp fragment was amplified from larynx and its secretion of the ILT-suspected chickens. And its amino acid sequence had 98.5% homology to that of ILTV TKgene published in GenBank. After the chicken embryos were inoculated with the isolated ILFV fluid, pox spots, giant polynuclear syncytial cells having intranuclear inclusion bodies were observed in CAM. After being challenged by the IL TV fluid, the chickens showed typical respiratory symptoms and pathological changes of ILT. [Coudusion] A field strain named ILTV XZ09 was isolated from larynx and its secretion of ILT-suspected chickens.

Screening of Chinese Herbal Medicines against Avian Infectious Laryngotracheitis Virus and Escherichia coli

[ Objective] This study aimed to screen Chinese herbal medicines against avian infectious laryngotracheitis virus and Escherichia coli. [ Method ] Conventional Chinese medicine plate dilution method, plate punching method and test tube method were applied to screen Chinese herbal medicines against avian infectious laryngotracheitis virus based on chicken embryo inoculation experiment. [ Result ] Forsythia suspensa, Radix lsatidis, Isatis iadigotica, Lonicera japonica, Codonopsis pilosula, Astragalus membranaceus, Rhizoma Atractylodis Macrocephalae, C, tyeyrrhiza uralensis and Pericarpium granati had relatively strong anti-ILTV effect; among the Chinese herbal medicines against avian E. coli, Sanguisorba offwinalis, Fructus Mume, Rheum palmatum, Anemarrhena asphodeloides, Radix Scutellariae and Fagopyrum cymosum had relatively strong effect against avian E. coli Os, while other Chinese herbal medicines had relatively weak or no inhibitory effect on avian E. coli 0s and 05. [ Conclusion] This study laid the foundation for further development of Chinese herbal medicine compound preparations to treat avian infectious laryngotracheitis, avian colibacillosis and other viral diseases and bacterial diseases.