The effects of co-exposure of Australian crude oil and ultraviolet radiation to yellowtail kingfish (Seriola lalandi) and black bream (Acanthopagrus butcheri) on hatching success and cardiac development

Yellowtail kingfish (Seriola lalandi) and black bream (Acanthopagrus butcheri) embryos were co-exposed to Australian crude oil and ultraviolet radiation at different points in development, and the effects were quantified on the hatched larvae. For each experiment, a high energy water accommodated fraction (HEWAF) of Australian crude oil at a loading rate of 1 g/L was prepared. Fish were exposed to dilutions of the HEWAF and either 10% or 100% ultraviolet radiation (outdoor sunlight) in a temperature controlled water bath to ensure temperatures in the exposure dishes did not exceed 25°C. Yellowtail kingfish embryos were exposed to dilutions of the HEWAF for approximately 32 hours, and then co-exposed to UV radiation for 4 hours. Following the UV exposure, the embryos were transferred to clean water and held at normal laboratory conditions (25°C, 14:10 light dark cycle) until hatch. At 48 h, hatching success, heart rate, incidence of edema were quantified. Images were taken of the larvae using a Leica M205C stereomicroscope to quantify pericardial edema using ImageJ (v1.49). Another experiment was conducted on yellowtail kingfish later in development. The embryos were exposed to oil for approximately 21 h during which hatch occurred, then co-exposed to UV radiation for 2.75 h as larvae. Following the exposure, the larvae remained in the exposure solution in normal laboratory conditions. Survival was quantified at 72 h and images were taken to quantify pericardial area using ImageJ (v1.49). Black bream embryos were exposed to dilutions of the HEWAF for a total of 4 h. After 2 h of oil exposure, the embryos were then co-exposed to UV radiation for 2 h. Following the UV co-exposure, embryos were transferred to clean water and remained in normal laboratory conditions until hatch. At 24 h, hatching success, heart rate, incidence of arrhythmia were quantified. Images of the hatched larvae were taken to quantify pericardial edema in ImageJ (v1.49).黄尾𫚕（Yellowtail kingfish, *Seriola lalandi*）与黑鲷（black bream, *Acanthopagrus butcheri*）的胚胎在发育的不同阶段与澳大利亚原油及紫外线辐射共同暴露，并对孵化出的幼体开展效应量化分析。 每次实验中，均制备加载率为1 g/L的澳大利亚原油高能量水可萃取组分（high energy water accommodated fraction, HEWAF）。将受试鱼类置于控温水浴中，暴露于HEWAF的稀释液以及强度为10%或100%的紫外线辐射（模拟户外日光），以确保暴露培养皿内的水温不超过25℃。 针对黄尾𫚕的第一组暴露实验：胚胎先在HEWAF稀释液中暴露约32小时，随后与紫外线辐射共同暴露4小时。紫外线暴露结束后，将胚胎转移至清洁水体，在常规实验室条件（25℃、14:10光暗周期）下培育至孵化。幼体孵化后48小时，量化记录孵化成功率、心率及水肿发生率。使用徕卡M205C体式显微镜（Leica M205C stereomicroscope）拍摄幼体图像，通过ImageJ（v1.49）软件量化心包水肿程度。 后续针对发育后期的黄尾𫚕开展第二组实验：将胚胎暴露于原油环境约21小时（期间完成孵化），随后以幼体形式与紫外线辐射共同暴露2.75小时。暴露结束后，幼体仍留存于暴露溶液中，维持常规实验室条件培育。暴露后72小时量化记录存活率，并拍摄图像以通过ImageJ（v1.49）软件量化心包面积。 针对黑鲷的暴露实验：胚胎全程在HEWAF稀释液中暴露总计4小时。在原油暴露2小时后，将胚胎与紫外线辐射共同暴露2小时。紫外线共同暴露结束后，将胚胎转移至清洁水体，在常规实验室条件下培育至孵化。幼体孵化后24小时，量化记录孵化成功率、心率及心律失常发生率。拍摄孵化幼体的图像，通过ImageJ（v1.49）软件量化心包水肿程度。