【摘要】 血卵涡鞭虫（Hematodinium spp.）是一类主要寄生于海洋甲壳类动物的寄生甲藻,其引发的流行病严重危害我国沿海重要养殖经济蟹类（三疣梭子蟹、拟穴青蟹）的渔业生产。孢子是血卵涡鞭虫水体传播过程中的关键生活史阶段,准确评估孢子活力并筛选可抑制其活力的药物,可为防控该寄生甲藻流行性病害提供重要依据。为此,本研究建立了基于计算机图像分析的血卵涡鞭虫孢子运动活力评估方法,评估了4种水产常用药物（苯扎溴铵、戊二醛、辛硫磷、聚维酮碘）对血卵涡鞭虫孢子运动活力的影响。结果显示,2h苯扎溴铵、戊二醛、辛硫磷、聚维酮碘对大孢子的半数效应浓度(EC₅₀)依次为0.380 mg·L^–1、1.411 mg·L^–1、1.808 mg·L^–1、108.694 mg·L^–1, 2 h苯扎溴铵、戊二醛、辛硫磷对小孢子的EC₅₀依次为0.172mg·L^–1、0.038mg·L^–1、0.101mg·L^–1。苯扎溴铵抑制两种孢子运动活力的效果明显优于其余3种药物,可作为水产养殖中防控血卵涡鞭虫流行病的候选药物,建议防治血卵涡鞭虫大孢子的泼洒浓度为0.38～1.72mg·L^–1,小孢子泼洒浓度为0.17～0.35mg·L^–1。以上研究结果为丰富血卵涡鞭虫孢子活力评估方法,筛选水产养殖应用药物防控血卵涡鞭虫流行病提供了参考。更多还原

【Abstract】 Hematodinium spp. are parasitic dinoflagellates infecting marine crustaceans. It can trigger an epidemic and thereby seriously threaten the aquaculture of economically important crab species along the coast of China,such as Portunus trituberculatus and Scylla paramamosain. Dinospore is the crucial life stage of Hematodinium during its waterborne transmission. Accurately assessing the activity of dinospores and screening for drugs that can inhibit their activity can provide the essential basis for preventing and controlling epidemics caused by this parasitic dinoflagellate. To address this issue, we developed a method for assessing the motility of Hematodinium dinospores using computer image analysis. The effects of four common aquaculture drugs（i.e., benzalkonium bromide, glutaraldehyde, phoxim, and povidone-iodine） on the motility of Hematodinium dinospores were evaluated. Results revealed that, after 2 h, the EC₅₀（median effective concentration） for benzalkonium bromide, glutaraldehyde,phoxim, and povidone-iodine on macrospores were 0.380, 1.411, 1.808, and 108.694 mg·L^-1, respectively. In addition, the EC₅₀ for benzalkonium bromide, glutaraldehyde, and phoxim on microspores were 0.172, 0.038, and 0.101 mg·L^-1, respectively, after 2 h. The inhibitory effect of benzalkonium bromide on the motility of two dinospores was notably superior to that of the other three drugs, making it a promising candidate for preventing and controlling the epidemic caused by Hematodinium in aquaculture. Recommended spraying concentrations for preventing and treating Hematodinium macrospores were 0.38–1.72 mg·L^-1, while for microspores, they were 0.17–0.35 mg·L^-1. These findings enrich the activity assessment system of Hematodinium dinospores and provide a reference for screening drugs for preventing and controlling Hematodinium epidemics in aquaculture.更多还原