罗非鱼的味觉敏感性

GUSTATORY SENSITIVITY OF TILAPJA ZULII

应用氨基酸和配合饵料的水提取液刺激罗非鱼上唇的味蕾,记录面神经纤维上的生物电变化,研究罗非鱼味觉的生理特征。罗非鱼的味觉反应全部是瞬间的位相性变化,反映了味觉的快适应性。在试验所用的12种刺激物中,以精氨酸、谷氨酸、天门冬氨酸和配合饵料水提取液的刺激效果最强,我们认为,这是由于外周味感觉器对于摄食信息物质具有特殊的敏感性。

The stimulatory effects of amino acids and extract of commercial vegetable-based diet on lip taste buds of Tilapia zillii were studied by recording the electrical activities from facial nerve in July 1985 -February 1986. The taste physiological character and relation between taste stimulants and feeding behavior were discussed.1. All taste neural responses of the fish were of phasic nature, suggesting fast gustatory adaptation.2. Glutamic acid, aspartic acid, arginine and extract of commercial vegetable-based diet among the 12 stimulants were the most effective.3. Taste response spectrum to amino acids of the fish was different from that of others. There was correlation between taste receptor sensitivities of Tilapia zillii and their feeding behavior. Taste receptors were most sensitive to glutamic acid and aspartic acid, which were potent stimuli in feeding. Taste receptors were the least sensitive to glycine and proline, which could ,not enhance feeding. So that, taste was the key of selective feeding.4. Arginine is indispensible amino acid for the fish. High sensitivity of the receptors to arginine also stimulates the fish to take more food rich in arginine.5. After commercial vegetable-based diet was fed for several months the receptors became more sensitive to its extract. It indicated an adaptation to taste mediated feeding.