目的：本研究藉由自行發展之圓水蚤(Daphnia pulex)泳動行為模式觀察系統，改良舊有之影像記錄方式，分析圓水蚤接觸有毒物質；界面活性劑及殺蟲劑後，泳動軌跡與泳動速度改變的現象。方法：設計圓水蚤泳動行為模式觀察系統，使用高畫素之數位相機記錄圓水蚤泳動軌跡，於固定時間截取圓水蚤之泳動軌跡並利用畫素(Pixel)定量圓水蚤泳動速度，運用Image J V3.6中之破碎維度(Fractal dimension)與Box counting method估算，並採用ANOVA統計分析。結果：研究結果顯示圓水蚤接觸界面活性劑於試驗時間0、30、60分鐘可觀察到泳動行為快速（約111, 000 pixel），路徑接近直線，與控制組（緩慢；約50, 100 pixel，路徑成拋物線）有明顯之差距。圓水蚤接觸殺蟲劑後，於試驗時間15分內即可觀察到其泳動速度有明顯之加速（約70, 750 pixel），且路徑接近直線到達亮點，觀察於暴露試驗時間一開始時，圓水蚤泳動速度即呈現出劑量效應之趨勢。分析軌跡之FD(Fractal dimension)值比較界面活性劑(Df=1.67)、殺蟲劑(Df=1.53)，經過統計分析(ANOVA)結果顯示殺蟲劑相較於界面活性劑，其對於圓水蚤之泳動軌跡有顯著之差距(P<0.001)。結論：本研究所自行設計之圓水蚤泳動行為模式經由以上試驗結果之分析證實，可提高偵測水中不同化學物質（界面活性劑及殺蟲劑）之敏感度。圓水蚤泳動行為模式觀察系統，可詳細記錄分析圓水蚤之行為模式，在短時間（15分鐘）內即可評估水體是否遭受汙染，對於運用圓水蚤泳動行為模式試驗有毒物質可做為反應時間之參考。
Purpose: In this study, we propose a new technique of evaluating the phototactic swimming behavior by recording and analyzing swimming tracks and speeds after exposure to a toxicant. Methods: We measured these outcome variables in freshwater cladoceran Daphnia pulex (water fleas) divided into three groups: surfactant stress, pesticide stress, and control. Swimming velocity was determined by a real time image analysis, using a digital camera, Image J V 3.6 fractal dimension and Box counting method. Swimming velocity as an outcome measure quantitated by pixel counting. The swimming tracks were analyzed by fractal dimension and ANOVA. Results: Daphnia pulex exposed to surfactants for 0, 30 and 60 minutes were observed to swim faster (111,000 pixel) than the control group (50,100 pixel). The escape mechanism, phototactic behavior, and escape from living stress phenomenon were found during the test. The phototactic swimming speed of animals exposed to pesticides, which significantly increased (70,750 pixel) or decreased within 15 minutes depending pesticide dosage. There was a significant difference in fractal dimension (FD value) between pesticide group (Df=1.53) and surfactant group (Df=1.67) (P<0.001). Conclusion: These methods may be used to measure the effect of surfactants and pesticides on other swimming aquatic organisms, and the results of these studies can be used as a reference when assessing reaction time in the swimming of water fleas exposed to various pollutants.
