日本鳗鲡仔鱼摄食机理及其营养策略

鳗鲡属(Ａｎｇｕｉｌｌａ)鱼类共有19种和亚种,其中以欧洲鳗鲡(Ａ.ａｎｇｕｉｌｌａ)和日本鳗鲡(Ａ.ｊａｐｏｎｉｃａ)最为重要。鳗鲡属鱼类发育需经历奇特的柳叶状仔鱼(ｌｅｐｔｏｃｅｐｈａｌｕｓｌａｒｖａ)阶段,其人工育苗技术是一道世界难题。柳叶状仔鱼现象仅见于真骨鱼类最原始的一个类群海鲢总目Ｅｌｏｐｏｍｏｒｐｈａ(鳗鲡目Ａｎｇｕｉｌｌｉｆｏｒｍｅｓ,海鲢目Ｅｌｏｐｉｆｏｒｍｅｓ,背棘鱼目Ｎｏｔａｃａｎｔｈｉｆｏｒｍｅｓ)。有关柳叶状仔鱼的发育策略,已从形态学、生理学及生物化学等方面进行了不少研究,但柳叶状仔鱼…

The feeding mechanism and nutritional strategy of early and leptocephalus larvae of Anguilla japonica

Leptocephalus larvae are the unique stage of larval development in all groups of fishes from the superorder Elopomorpha ( Anguilliformes, Elopiformes and Notacanthiformes) . To explain the leptocephalus strategy of larval development, various attempts have been made on the morphology, physiology and biochemistry of leptocephalus larvae. However, the feeding mechanism of leptocephalus larvae is st ill unknown. The Japanese eel ( Anguilla japonica ) larvae were found to have well developed scotopic vision, mechanoreception and chemoreception. Both early and leptocephalus larvae of Japanese eel actively ingested a kind of paste food by first touching the food with their snout and then tearing off a big mouthful of the paste with their sharp teeth. Chemoreception was shown to be critical to elicit the feeding response. Feeding by S-f lex posture from a distance might be of some significance for the early larvae to catch movable food. It is proposed that that the natural food of Japanese eel larvae would be relatively large, rather soft, inactive and negatively phototactic. The developmental mode of sensory system and behavior of Japanese eel larvae seems to be similar to some deep sea fishes but contrast w ith most marine teleost fishes.