碩士 / 國立臺灣大學 / 動物學研究所 / 97 / Photobacterium damselae subsp. Piscicida (Pdp) has been a major pathogen causing serious mortality of cultured cobia in the past years in Taiwan, particularly when they are moved into sea cage. Vaccination is a fundamental strategy to prevent the outbreak of bacterial diseases. In this study, several immune program factors of Pdp vaccine, including inactivated agent, immune dosage, adjuvant, boost immune, and immunostimulant were investigated to verify the influences on inducing specific immunity and the ability against Pdp infection in cobia. Our results revealed that 0.5% formalin could completely inactivate Pdp and retain higher antigenicity than 0.5% β-propiolactone did. The specific antibody titer caused by high dosage antigen (0.333 mg/g) was higher than low dosage (0.006 mg/g). Compare the influences on inducing specific antibody titer of different adjuvants in Pdp vaccines, aluminum hydroxide exhibited the highest immune effect among all adjuvants, although with a relatively shorter duration. Due to the low memory of cobia immunity, a second vaccination was required to enhance the immunity efficacy and protection period. No significant differences were observed between Pdp vaccine with or without adding inactivated extracellular product. Compare the antibody titer induced by Pdp vaccine with ISA 763A adjuvant or with fish oil adjuvant embedded as water in oil in water (WOW group), the duration of ISA group was longer than WOW group after boost. Besides, the cumulative mortality of ISA group was 40% lower than negative control (100%) after intraperitoneal challenge. Cobia immunized by Pdp vaccine was supplemented in Vibrio anguillarum (V.ang) and Astragalus polysaccharide (APS) showed the best protection efficacy after immersion challenge. However, the cumulative mortality was higher than that without APS after intraperitoneal challenge. It is suggested that APS may lower Pdp infection by inducing non-specific immunity in mucus. There is no enhancement on specific immunity and protection effect when inactivated V.ang was supplemented in Pdp vaccine ; contrarily it seems to interfere Pdp vaccine protection efficacy.
| Identifer | oai:union.ndltd.org:TW/097NTU05312002 |
| Date | January 2009 |
| Creators | Yi-Chun Fang, 方宜鈞 |
| Contributors | 齊肖琪 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 68 |
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