饲料中添加虾青素对血鹦鹉体色的影响

目的]探讨血鹦鹉鱼增色饲料中虾青素的最适添加量及着色规律。方法]在基础饲料中分别添加3‰、5‰、8‰的虾青素和5‰虾青素+20μg/kg的甲基睾酮,投喂7 cm左右的鹦鹉鱼进行增色试验。应用SalmoFanTM(帝斯曼有限公司)比色板测定色度,观察增色过程中血鹦鹉的体色变化。结果]5‰和8‰虾青素组增色效果好于3‰虾青素组,但5‰和8‰组间差异不显著。5‰虾青素+20μg/kg的甲基睾酮组在试验开始后1周内色度增加速度高于5‰虾青素组,但长期增色效果两组差异不显著。各试验组血鹦鹉色度增加随时间变化趋势基本一致,试验开始后10 d内,色度增加速度较快,而后色度增加的速度趋于平缓,进入平台期。结论]鱼体解剖结果显示,虾青素主要沉积在血鹦鹉鱼的皮肤上。

Effects of Astaxanthin on the Color of Blood Parrot

Objective] The optimum level of astaxanthin in feed and the body coloring of blood parrot fish were discussed.Method] Fundamental feed enriched with 3‰,5‰ and 8‰ astaxanthin,5‰ astaxanthin +20 μg/kg methyltestosterone(MT) were fed to 7 cm long blood parrot.The changes of body color were valued and recorded by SalmoFanTM.Result] The groups with 5‰ and 8‰ astaxanthin were better than 3‰ group.There were no significant differences between 5‰ and 8‰ groups.When combined with 20 μg/kg MT,color scores increased more quickly than 5‰ group.However,the effects of both groups had no significant differences at the end of coloring.All groups had consistent directions of color scores increase,which color scores increased quickly within 10 d,and presented a plateau phase with lower increase rate on color scores.Conclusion] Astaxanthin was found to be deposited on the skin of the fishes according to the fish anatomy result.