碩士 / 國立海洋大學 / 水產養殖學系 / 87 / The 96-h LC50 of copper on tiger shrimp Penaeus monodon was 3.13, 7.73 and 7.38 mg/l at 15, 25 and 35 ppt, respectively. The safe value of copper was P. monodon (0.625 ± 0.134 g) was estimated to be 0.31, 0.77 and 0.73 mg/l at 15, 25 and 35 ppt, respectively.The survival rate of P. monodon (0.158 ± 0.024 g)following 75 days exposure to 0 (control), 0.46, 0.88, 1.77 and 4.27 mg/l copper was 100 %, 100 %, 77.8 %, 50 % and 0 %, respectively. The body weight and total length of P. monodon exposed to 0.88 ml/l copper was significantly lower than that in the control shrimps. The ratio of carapace length to total length of P. monodon exposed to 0.88 and 1.77 mg/l was significantly higher than that in the control shrimps. The concentration that reduced weight gain and length increase by 50 % of that of the controls after 75 days was 1.65 and 1.50 mg/l copper.The time to the first molting for the P. monodon exposed 0, 0.46, 0.88, 1.77 and 4.27 mg/l copper was 5.5, 4.67, 4.28, 3.94 and 3.33 days. The intermolt period of shrimps during 75 days exposure to 0, 0.46, 0.88, 1.77 and 4.27 mg/l copper was 8.96, 8.87, 9.70, 10.17 and 10.88 days, with molting frequency of 2.50, 2.72, 2.47, 2.21 and 2.14 times, respectively. It is concluded that use of copper sulfate may remove filamentous algae, however the remain of copper sulfate in water may increase intermolt period and reduction of molting frequency leading to retarded growth of cultured shrimps.The feeding rate of shrimps (6.246 ± 0.091 g) exposed to 4.32 mg/l copper was only 50 % of that in the control shrimps. However, no feeding was observed for the shrimps exposed to 18.24 mg/l copper.Ammonia-N excretion of shrimps (23.84 ± 1.53 g) decreased, whereas urea-N excretion and organic-N excretion increased with concomitant increase of hemolymph ammonia and urea when the shrimps were exposed to elevated copper. The contribution of ammonia-N excretion, urea-N excretion and organic-N excretion in a total-N excretion of P. monodon was 84.3 %, 6.4 % and 7.4 %, respectively. The decrease of ammonia-N excretion with increase of urea-N excretion and organic-N excretion were observed for the shrimps exposed to elevated copper. Copper uptake of shrimps exposed to 18.81 mg/l copper after 24 h was 68.44 μg/g/h. Hemolymph glucose concentration decreased with increase of elevated copper concentration, and the hemolymph glucose was 60 % of that in the control shrimps.Oxygen consumption recovered in 16 h for the shrimps following 24 h exposure to 10 mg/l copper and then depuration in copper-free water. Ammonia-N excretion recovered to 61 % of that in the control shrimps when the shrimps were exposed to copper after 24 h and then depurated in copper-free water. Water exchange is necessary for the shrimp pond after application of copper sulfate to reduce its effect on nitrogenous metabolism of cultured shrimps.
| Identifer | oai:union.ndltd.org:TW/087NTOU0086015 |
| Date | January 1999 |
| Creators | Jia-Sin Lin, 林家興 |
| Contributors | Jiann-Chu Chen, 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 | 117 |
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