基于计算机视觉的罗非鱼适应环境的体色变化研究

多数鱼类的体色会受应激条件、环境背景、健康状况、生长发育和社会地位等因素的影响而发生改变。本文利用基于计算机视觉的体色量化技术研究正常情况和社会应激条件下罗非鱼对背景颜色的适应性，以及在背景颜色变化过程中体色变化的响应速度。实验结果表明：已适应白色背景的鱼放入黑色背景水体后，体色变化主要发生在前10s内，放入时和放入10s后的体色明度值差异极显著（**p＜0.01）；在白色背景下适应的鱼放入黑色背景下适应2h后其体色变得很黑，将其放入白色背景水体后体色在10s内可发生由深到浅的变化，放入时和放入10s后的体色明度值差异极显著（** p＜0.01）。在蓝色背景下适应的鱼放入黑色背景水体后，体色变化主要发生在前10s内，放入时和放入10s后的体色明度值差异显著（*p＜0.05）。在蓝色背景下适应的鱼放入黑色背景下适应2h后的体色变得很黑，再将其放入白色背景水体后体色由深变浅，放入时和10s后的体色明度值发生极显著变化（**p＜0.01）。处于社会应激条件下劣势地位的鱼体色会变黑，刚放入白色背景水体时的平均灰级达到12.7阶，放入60s、1800s后的体色和刚放入时没有显著差异。受社会应激影响轻微的鱼体色在1800s后适应了环境的颜色，明度值和没有受应激影响鱼的体色接近，而受伤或受社会应激影响较严重的鱼体色改变较小。鱼在高浓度非离子氨（UIA浓度为0.178 mg/L）的水中处理3h后，鱼的体色变得很黑，刚放入白色背景水体时平均灰级达到15.1阶，放入10s、120s后鱼的体色变化不大，放入180s后鱼的体色变浅，平均灰级达到9.3阶，与刚放入时的体色明度相比差异显著（*p＜0.05）。

Study on color modification of tilapia Oreochromis niloticus under environmental background and stress by computer vision

Some fish color modification can occur under stress conditions, environment background color, health status, fish reproductive period, along with social class. The skin color of tilapia adapted to background color under normal conditions and social stress conditions, as well as skin color modifications response rate during color modification period, were investigated by fish color quantifying technology based on computer vision. The results showed that skin color modification of tilapia had adapted white background happened in the first 10s while putting tilapia into the aquarium with black background, and the lightness level of the skin color had much significant modification (**p < 0.01) in 10 seconds. The skin color of tilapia had adapted white background appeared deeply black while putting tilapia into the aquarium with black background for 2h, and then the color changed from deep color to tint in 10 seconds while putting tilapia into the aquarium with white background, the lightness level of the skin color had much significant modification (**p < 0.01) in 10 seconds. The skin color modification of tilapia had adapted blue background happened in the first 10s while putting tilapia into the aquarium with black background, and the lightness level of the skin color had significant modification (*p < 0.05) in 10 seconds. The skin color of tilapia had adapted blue background appeared deeply black while putting tilapia into the aquarium with black background for 2h, and then the color changed from deep color to tint in 10 seconds while putting tilapia into the aquarium with white background, the lightness level of the skin color had much significant modification (**p < 0.01) in 10s. The tilapia color modification can changed black under social stress. The mean density steps of color researched 12.7 ranks while putting tilapia into the aquarium with white background and the lightness level of the skin color had no significant modification after 60s and 1800s in white background. The skin color of tilapia suffered lower social stress conditions can adapted the environment color after 1800s and the lightness level of the skin color was similar with those in normal conditions. The lightness level of the skin color of tilapia was hurt and suffered severe social stress changed little. The skin color of tilapia treated with high UIA (0.178 mg/L) became darker and the mean density steps of color researched 15.1 ranks while putting tilapia into the aquarium with white background and the lightness level of the skin color had no significant modification after 10s and 120s in white background. The mean density steps of color researched 15.1 ranks at 180s and the lightness level of the skin color had significant modification (*p < 0.05).