鳜鱼食性奇特，终生以活鱼虾为食，通常拒食死饵或配合饲料，其人工饲料可控养殖问题亟待研究解决。鳃耙是鱼类的滤食器官，与食性密切相关。前期研究发现edar基因与鳜鱼鳃耙发育密切相关，且edar激活后显著影响斑马鱼的开口摄食选择。本项目通过激活/抑制鳜仔鱼edar，检测鳃耙发育情况及相关基因mRNA和蛋白表达水平，研究edar对鳜鱼鳃耙发育的调控作用及开食期鳃耙数目对鳜仔鱼开口饵料选择的影响；利用已构建的edar敲除斑马鱼模型研究edar缺失对开食期饵料规格选择的影响，验证edar调控鳃耙发育进而影响开口饵料选择的分子机制。最后，通过对开口饵料选择不同但已形成稳定摄食的鳜鱼返投喂饲料，研究开口饵料选择对后期食物印记的影响，探讨edar基因调控鳜鱼鳃耙发育及食性形成的机理，为促进易驯食人工饲料鳜鱼新品种成功培育奠定必要的理论基础。

Mandarin fish as an absolutely carnivorous fish, is the most famous high valued fish species in China. Under cultivation, mandarin fish only consume live prey fish throughout their life and refuse dead prey fish or artificial diets. This problem has been widely known as a hard nut to crack in the field of aquaculture in China. Gill rakers play an important role in suspension feeding by determining the size of appropriate food particles, especially in first-feeding. Mandarin fish do not accept zooplankton and exclusively rely on live prey fish, possibly due to their very few gill rakers. Ectodysplasin A receptor (edar) is essential to gill raker development. In our previous study, a ‘gill raker-loss’ phenotype was observed in edar knockout zebrafish and the mutant zebrafish showed reduced food intake of zooplankton, increased food intake of prey fish. In the present study, the effects of edar activator and inhibitor on gill raker number, edar mRNA expression level and protein level will be examined by Alcian blue staining, scanning electron microscope, whole-mount in situ RNA hybridization, qRT-PCR and Western blot, respectively. The effects of gill rakers on first-feeding will be performed with brine shrimp and live prey fish. To clarify the molecular basis, the effects of edar on first-feeding will be further examined in edar knockout zebrafish. Finally, after treatment, mandarin fish will be fed with artificial diets to explore the effect of first-feeding selection on food imprinting. The results of the present study would provide strong foundation for the breeding of new mandarin fish strain with good performance in feeding artificial diets.