Dey Bapon, Kawabata Fuminori, Kawabata Yuko, Nishimura Shotaro, Tabata Shoji
Laboratory of Functional Anatomy, Faculty of Agriculture, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka, 812-8581, Japan.
J Poult Sci. 2018;55(3):204-209. doi: 10.2141/jpsa.0170188. Epub 2018 Jan 25.
Bitterness is one of the five basic tastes, and sensitivity to bitterness is important in that it enables animals to avoid harmful and toxic substances. In humans, taste sensitivity decreases with age, although the extent of loss varies depending on the taste quality. In chickens (), baby chicks have been found to be more sensitive to salt and sour taste qualities than adults. In this study, therefore, we investigated the growth-associated changes in bitter taste sensitivity in chicks. We examined the behavioral perceptions toward the bitter compounds chloramphenicol and andrographolide in chicks at three different growth stages. Then, we measured the relative expression of the functional bitter taste receptors in the chick palate. In behavioral drinking tests, the 0-1-week-old chicks consumed a significantly lower amount of bitter solutions than water, whereas the 8-9-week-old chicks showed lower avoidance of the bitter solutions than the 0-1-week-old and 4-5-week-old chicks. Real-time PCR assay showed that the 0-1-week-old chicks had significantly higher expression of one of the functional bitter taste receptors in the palate than that in the older chicks. These results suggest that baby chicks are more sensitive to bitterness than older chicks. These findings may be useful in the production of new feedstuff for chicks according to their growth stages.
苦味是五种基本味觉之一，对苦味的敏感度很重要，因为它能使动物避开有害和有毒物质。在人类中，味觉敏感度会随着年龄增长而下降，不过下降程度因味觉品质而异。在鸡身上，已发现雏鸡对咸味和酸味的敏感度比成年鸡更高。因此，在本研究中，我们调查了雏鸡苦味敏感度与生长相关的变化。我们检测了雏鸡在三个不同生长阶段对苦味化合物氯霉素和穿心莲内酯的行为感知。然后，我们测量了雏鸡腭部功能性苦味受体的相对表达。在行为饮水测试中，0至1周龄的雏鸡饮用苦味溶液的量明显低于饮水，而8至9周龄的雏鸡对苦味溶液的回避程度低于0至1周龄和4至5周龄的雏鸡。实时聚合酶链反应分析表明，0至1周龄雏鸡腭部一种功能性苦味受体的表达明显高于大龄雏鸡。这些结果表明，雏鸡比大龄雏鸡对苦味更敏感。这些发现可能有助于根据雏鸡的生长阶段生产新的饲料。
