Safety and immunoprotectivity of inovojection and conventional immunization of fowl pox and infectious laryngotrachitis vaccine in chickens

• Main Author: 吳子熊
• Other Authors: Maw-Yeong, LIN
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/88206038506458805950

碩士 === 國立屏東科技大學 === 獸醫學系 === 91 === Each of 15 groups, 10 commercial broilers or embryos per group, in 2 trials was individually vaccinated with a commercial fowl pox vaccine at 10-day-old or 18-day-embryos by wingweb stabbing or inovojection respectively for comparison of the safety in terms of hatchbility and survival rate and protectivity against the recently local pox viruses challenge of the pox vaccines in 2 trials as a reference for choosing the best pox vaccine used in field as well as to evaluate the applicability of the in ovo vaccination of the pox vaccine for commercial broilers. A nonimmunized but challenged group was also included in each trial. Four (K-2, I-2, I-3 and L) and one (I-2) pox vaccines by wingweb stabbing and inovojection respectively were found with good safety and protectivity. The pox vaccine virus was found more virulent to commercial broiler embryos than broilers. Therefore, the in ovo vaccination of pox vaccine provides less safe and protective than wingweb stabbing vaccination less. One (I-2) pox vaccine has some good potential for developing as in ovo vaccine. Each of 11 groups, 10 commercial broilers or embryos per group, in 2 trials was individually vaccinated with a commercial live infectious laryngotrachitis (ILT) vaccine at 10-day-old or 18-day-embryos by eye-drop or inovojection respectively for comparison of the safety in terms of hatchbility, morbility and mortality as well as the enzyme-linked immunosorbent assay (ELISA) of ILT vaccines in 2 trials as a reference for chosing the best ILT vaccine used in field and to evaluate the applicability of the in ovo vaccination of live ILT vaccine for commercial broilers. A nonimmunized but challenged group was also included in each trial. In live ILT vaccine eye-drop immunization trial, all the groups did not present any morbility or mortality at 10 days post vaccination. The geometric mean titer (GMT) of ILT-ELISA in the immunized groups ranged from 27 to 2845. In live ILT vaccine inovojection trial, Six groups had the embryo mortality range from 6.7% to 13.3%, 8 groups had the mortality at 23 days post vaccination range from 47% to 100%, the GMT of ILT-ELISA range from 43 to 5224, but still had 3 immunized groups with the embryo mortality and mortality at 23 days less than 14%. Commercial live ILT vaccine viruses are safe for use in commercial broilers by eye-drop, but are so virulent to commercial broiler embryos to be used as inovojection. Three ILT vaccines evaluated in this study might have some good potential to be developed as in ovo vaccine.