碩士 / 國立臺灣海洋大學 / 水產養殖學系 / 93 / Addition of NaCl at 2.5 % to tryptic soy broth (TSB) significantly increased the growth of Photobacterium damselae subsp. damselae. Tiger shrimp Penaeus monodon acclimated in 25 ‰ seawater were injected with P. damsela subsp. damselae grown in TSB containing NaCl at 0.5, 1.5, 2.5 and 3.5% at a dose of 8.48 x 104 colony-forming units (cfu) shrimp-1. Over 24-96 h, the cumulative mortality was significantly higher for the shrimp challenged with P. damselae subsp. damselae grown in 2.5% NaCl than those grown in 0.5, 1.5 and 3.5% NaCl. In other experiment, P. monodon acclimated in 25 ‰ were injected with TSB-grown P. damselae subsp. damselae at 8.48 x 104 cfu shrimp-1, and then transferred to 5, 15, 25 (control) and 35 ‰. After 96 h, the mortality was the highest for the P. damselae subsp. damselae-injected shrimp held in 5 ‰, and the lowest for the P. damselae subsp. damselae-injected shrimp held in 25 ‰. P. monodon held in 25 ‰ and then transferred to 5, 15, 25 (control) and 35 ‰ were examined for immune parameters, and phagocytic activity and clearance efficiency to P. damselae subsp. damselae after 12-96 h. The THC (total haemocyte count), DHC (differential haemocyte count), phenoloxidase activity, respiratory burst, superoxide dismutase (SOD) activity, phagocytic activity and clearance efficiency decreased significantly for the shrimp transferred to 5, 15 and 35 ‰ after 12 h. It is concluded that P. damselae subsp. damselae reared in 2.5 % NaCl showed higher virulence to P. monodon. It is also concluded that P. monodon transferred from 25 ‰ to low salinity levels (5 ‰ and 15 ‰) and high salinity (35 ‰) had reduced immune ability and decreased resistance against P. damselae subsp. damselae infection.
Tiger shrimp P. monodon held in 26 ℃ at 25 ‰ were injected with TSB-grown P. damselae subsp. damselae (8.48 x 104 cfu shrimp-1), and then transferred to 22, 26, 30, 34 ℃. Over 96 h, the mortality of P. damselae subsp. damselae-injected shrimp transferred to 22 and 34 ℃ was significantly higher than that of shrimp transferred to 26 (control) and 30 ℃. Shrimp held in 25 ‰ and 26 ℃, then transferred to 22, 26, 30 and 34 °C were examined for THC, DHC, phenoloxidase activity, respiratory burst, SOD activity after 12-96 h. The THC, DHC, phenoloxidase activity, respiratory burst and SOD activity decreased for the shrimp transferred 22 ℃ after 12-48 h. It is concluded that the shrimp transferred from 26 ℃ to low temperature (22 ℃) had reduced immune ability and decreased resistance against P. damselae subsp. damselae infection.
| Identifer | oai:union.ndltd.org:TW/093NTOU5086021 |
| Date | January 2005 |
| Creators | Wang Feng-I, 王鳳儀 |
| Contributors | Chen Jiann-Chu, 陳建初 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 87 |
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