碩士 / 國立臺灣海洋大學 / 水產養殖學系 / 96 / White shrimp Litopenaeus vannamei juveniles (body weight 1.15 ± 0.21 g) were exposed to different concentrations of residual chlorine at different salinity levels (15?, 25? and 35?) using the static renewal method. Bioassay experiments to establish tolerance limits were conducted in 2-l plastic containers containing 1-l test solutions. Each tank contained 10 shrimp, and each test solution was conducted in triplicate. The nominal concentrations of chlorine used were 2.4, 2.8, 3.2, 3.6, 4.0, 4.4, 4.8, 5.2 mg l-1; 3.6, 4.0, 4.4, 4.8, 5.2, 5.6, 6.0, 6.4 mg l-1; and 4.8, 5.2, 5.6, 6.0, 6.4, 6.8, 7.2, 7.6 mg l-1 for the experiments at 15?, 25?, and 35?, respectively.
The Lt50 (median lethal time, h) value required to kill half the population were 68.8, 43.6, 26.8, 24, 18.2, 12.9, and 9.6 h for the test solution of 2.8, 3.2, 3.6, 4.0, 4.4, 4.8 and 5.2 mg l-1, respectively at 15?. The Lt50 was 130.9, 95.5, 38, 31.2, and 25.5 h for the test solution of 4.8, 5.2, 5.6, 6.0, and 6.4 mg l-1, respectively at 25?. The Lt50 was 108, 77.6, 39.7, 27.4 and 16.6 h for the test solution of 6.0, 6.4, 6.8, 7.2, and 7.6 mg l-1, respectively at 35?.
The concentration response of test organisms was determined for LC50 (median lethal concentration) values and their 95% confidence limits with a probit computer program. The 6-, 12-, 18-, 24-, 36-, 48-, 60-, 72-, 84-, 96-, 108-, 120-, 132-, and 144-h LC50 of chlorine on L. vannamei juveniles were 5.60, 5.49, 4.55, 4.07, 3.69, 3.22, 2.93, 2.83, 2.67, 2.58, 2.56, 2.44, 2.44, and 2.44 mg l-1 at 15?; 7.46, 7.01, 6.99, 6.86, 6.32, 6.16, 5.54, 5.14, 5, 4.86, 4.79, 4.77, 4.77, and 4.73 mg l-1 at 25?; and 8.51, 8.12, 7.79, 7.59, 7.44, 6.95, 6.59, 6.30, 5.88, 5.81, 5.69, 5.71, 5.70, and 5.61mg l-1 at 35%, respectively. The “safety level” for rearing L. vannamei juveniles was calculated to be 0.26 mg l-1, 0.49 mg l-1 and 0.58 mg l-1 for the experiments at 15?, 25?, and 35?, respectively.
The relationship between survival, salinity, chorine concentration and exposure time, and the relationship between chlorine, salinity and exposure time were established. The relationship among survival (%), chlorine concentration (C), salinity (S), exposure time (t) and the interaction among salinity and chlorine concentration (SC), salinity and exposure time (St), chlorine concentration and exposure time (Ct), and salinity, chlorine concentration and exposure time (SCt) is as follows:
Survival（%）= 0.97527+ 0.00427S -0.12519C -0.00343t + 0.00228SC
+ 0.00014St -0.00055Ct - 0.00001SCt （R2=0.7720）
The relationship among LC50 of chlorine concentration (mg l-1), salinity (S) and exposure time (t) is as follows:
LC50= 2.66078 + 0.16421S - 0.02140t (R2=0.8355).
| Identifer | oai:union.ndltd.org:TW/096NTOU5086045 |
| Date | January 2008 |
| Creators | Fabiola Victoria Arce Nunez, 艾薇欣 |
| Contributors | Jiann-Chu Chen, 陳建初 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | en_US |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 51 |
Page generated in 0.8408 seconds