›› 2009, Vol. 36 ›› Issue (1): 86-87.

• 疾病防治 • Previous Articles     Next Articles

Study on the EE Ratio as an Indicator of Dwarfism Induced by Infectious Bronchitis Virus

CHENG Yahui, CUI Baoan, LI Xinsheng, LI Shuangliang, FENG Lixia, GAO Wenming   

  1. College of Animal Husbandry and Veterinary Science, Henan Agricultural University,Zhengzhou 450002,China
  • Received:1900-01-01 Revised:1900-01-01 Online:2009-01-20 Published:2009-01-20

Abstract: Avian infectious bronchitis virus (M41,H120,HN99) were inoculated in chicken embryos.The eggs and the respective embryos were weighed and embryo:egg weight (EE) ratios were calculated within 6 days post inoculation.The EE ratios were compared with the uninoculated control embryos and EID50 could be calculated objectively. EE indices were also calculated by dividing the EE ratios of inoculated chicken embryos by the mean EE ratio of uninoculated controls. The results indicated that values of M41 and HN99 differ significantly from the respective fourth day EE ratio of uninoculated control embryos, and H120 differ significantly from the respective fifth day EE ratio of uninoculated control embryos, then the preliminary determination is to be infectioned by the infectious bronchitis virus. This method would be useful to observe embryo lesions especially in field strains of infectious bronchitis virus, which does not cause observable dwarfing until several embryo passages.

Key words: infectious bronchitis virus; EE ratio; EE indices