碩士 / 國立屏東科技大學 / 水產養殖系所 / 99 / Student ID: M9813012
Title of Thesis: Usage of electrolytic water system in giant freshwater prawn
hatchery
Total Page: 88
Name of Institute: Department of Aquaculture, National Pingtung
University of Science and Technology
Graduate date: June 20, 2011 Degree conferred: Master
Name of Student: Li Fan Sie Adviser: Dr. Chun Hung Liu
Dr. Shinn Pyng Yeh
The Contents of Abstract in This Thesis:
The purpose of this study is to use electrolytic water system in the giant freshwater prawn (Macrobrachium rosenbergii) hatchery while analyze its feasibility application on disease control and water quality improvement. In order to understand the relationships among salinities、flow rates、electric power and effectiveness in production of available chlorine, this study will include different salinities (15 and 30‰), flow rates (3 and 6 L/min), and electric powers (1 and 5 W). The results showed that the available chlorine in electrolytic water was increased as the salinitly and electric power increased. However, the available chlorine production was negative related to flow rate. The experiment showed that the growth of six important aquatic pathogens were well inhibited by incubation with 0.5 mg/L and 1 mg/L of available chlorine in electrolytic water for 30 and 60 seconds, and the 1 mg/L of available chlorine has batter bactericidal effect in Vibrio alginolyticus (host Taiwan abalone), V. alginolyticus (host White shrimp), Vibrio vulnificus (host White shrimp), Photobaterium damsela subsp. damselae (host Tiger shrimp), Streptococcus sp. (host Giant grouper), and Vibrio parahemolyticus (host Taiwan abalone) than that of 0.5 mg/L. In addition, the removal of nitrogen compounds by electrolysis at different salinities (15 and 30‰) and fixed electric power at 5 W have significant effects. The electrolytic water could effectively remove the ammonia-N (NH3-N) and nitrite-N (NO2-N) in which the concentration of NH3-N and NO2-N reached 0 mg/L after 30 min and 10 min, respectively, of reaction with electrolytic water. In order to know more about the possibilities application of electrolytic water on the giant freshwater prawn hatchery, the toxicity test was done. The trial included different concentrations of available chlorine, 0, 0.2, 0.3, and 0.4 mg/L, in which larvae had the mortality of 0%, 12%, 27%, and 42%, respectively after 72 hours, Three types of method on reducing the residue of available chlorine in the electrolytic water including control (without treatment), vigorous aeration (1 L/min), and filtration through activated carbon (50 g) were used in this trial. The best approach for reducing the availabe chlorine is activated carbon which reduces the available chlorine from 10 mg/L down to 1.7 mg/L after 10 min. In order to make sure the electrolytic water was safe for larvae after filtered through activated carbon (50 g), prawn larvae were reared in activated carbon treated electrolytic water, which contain the available chlorine at initial concentration of 0, 0.5, 1, and 2 mg/L, and no dead larvae was observed within 60 hours. Base on the results from the preliminary experiments, the on farm usage of electrolytic water system in giant freshwater prawn hatchery could effectively reduce the total bacteria count, nitrogen compounds, and increased the growth and survival rate of prawn larvae. The prawn in electrolytic water group developed faster than in activated carbon group in which post-larvae was first seen at 28 day, and > 90% of larvae reached post-larvae at 31 day, while the carbon group had the first post-larvae at 31 day, and > 90% of them metamorphosed to post-larvae at 40 day. At the end of experiment, the survival rate of prawn in electrolytic water group was significantly better than that of the carbon group, in which the former is at 7.6% and the latter is 2.9%. These results had make us to believe that the electrolytic water group has excellent water quality and lower bacterial count resulting in accelerated larval development and increased survival rate.
| Identifer | oai:union.ndltd.org:TW/099NPUS5086003 |
| Date | January 2011 |
| Creators | Li Fan Sie, 謝立帆 |
| Contributors | Dr. Chun Hung Liu, Dr. Shinn Pyng Yeh, 劉俊宏, 葉信平 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 88 |
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