側線在斑馬魚打鬥行為所扮演的角色

The roles of lateral line on fighting behavior in zebrafish (Danio rerio)

胡祐桓(Yu-Huan Hu)

指導教授 ： 周銘翊

國立臺灣大學/生命科學院/生命科學系/碩士(2020年)

https://doi.org/10.6342/NTU202100895

摘要

動物為了有限的資源會透過同種間打鬥建立社會階層。在打鬥中正確的決策不只是對於準確的進攻重要，對於損害控制也很重要。許多感覺系統都被用作取得足夠的資訊，包括側線系統。側線的作用在於使斑馬魚能夠感測周遭水流的移動。先前研究指出側線系統在打鬥中扮演重要的角色，然而打鬥過程中，調控決定與評估的細節與相關的神經迴路仍然不清楚。我們發現新黴素去除側線後，焦慮與攻擊性會增加，社交性與體能則不受影響，且側線被去除的魚顯示出高傾向會在與控制組的魚打鬥中失利。透過對於行為細節的分析，我們發現側線系統影響到斑馬魚的判斷與認知，而非影響到攻擊的能力。為了更進一步的調查腦中的神經活性，我們利用原位雜合反應配合Egr-1與c-fos核醣核酸探子，一種常見的神經活性標記，以研究目標核區腹側韁核的狀態變化。打鬥後，側線去除的魚顯示出較其手足顯著高的腹側韁核活性。我們的研究結果顯示側線能夠影響打鬥中的判斷與認知，並影響到行為的決定與打鬥的結果。並且我們提出側線可能透過協調腹側韁核的活性來調節社會性鬥爭的結果。

關鍵字

側線 ； 斑馬魚 ； 打鬥行為 ； 腹側韁核 ； 動物行為

並列摘要

Male zebrafish (Danio rerio) often establish social hierarchy via conspecific fighting due to limited resources. To collect sufficient information during fighting, many sensory systems are employed including the lateral line (LS), a flow sensor, which enables fish to detect water movement. Even though the lateral line has been proved to modify a wide variety of behaviors, the mechanism by which lateral line participate in the modification of behavior is not completely explored. We found that zebrafish showed higher anxiety and aggression, while social preference and fitness were unaffected after the neomycin-induced lateral line ablation. Moreover, the lateral-line-ablated fish showed higher tendency to lose the fight against their sham-treated siblings. Nevertheless, swimming ability remain unchanged after neomycin treatment. To further investigate the neural activity in the brain, we used in situ hybridization with EGR-1 and c-fos riboprobes, common markers for neural activity, to visualize the change of neural activities in the targeted nucleus, the ventral habenula (vHb). The activation of the vHb was significantly higher in the lateral-line-ablated fish than in their siblings after fighting. Our result suggests that the lateral line ablation affects the evaluation and behavior but not physical fitness, and therefore determines the outcomes of social conflict. Moreover, we propose that lateral line may determine the outcomes of social conflicts through mediating the neural activity in the vHb.

並列關鍵字

Lateral line ； Zebrafish ； Fighting ； The ventral habenula ； Animal behavior

參考文獻

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