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ID 53071
フルテキストURL
タイトル(別表記)
Why do rabbits ingest their feces ?
著者
坂口 英 岡山大学農学部
抄録
 The utilization of dietary energy and protein must depend on microbial activity in the gut in every herbivore. For animals adopting the cecum as a microbial habitat, from the viewpoint of the protein utilization, the position of the cecum in the digestive tract is less advantageous than that of foregut fermenters. As a solution to this problem, cecum fermenters perform cecotrophy in order to utilize microbial protein proliferating in the cecum. Cecotrophy is supported by the mechanism that separates microbes from digesta in the colon, sends them back into the cecum and promotes microbial proliferation in the cecum. The colonic separation mechanism can be classified into two types. One is the mucus-trap type separation of bacteria with mucus from digesta in the proximal colon of rodents. The other is the wash-back type separation of particle phase of the colonic contents and liquid phase containing microbes in the colon of rabbits. For microbes guaranteed to inhabit the cecum under colonic separation mechanism, it is necessary for them to obtain sufficient nutrients for survival and proliferation. The source of nitrogen is easily obtained as urea transfered from the blood flow. On the other hand, the energy source is considered to be the limiting factor for bacterial proliferation due to the limited amount of easily usable energy source. In fact, cecal microbial proliferation of rabbits and guinea pigs increases when adding indigestible but fermentable sugars to the feed. As a result, the amount of cecotrophy increases, and the percentage of nitrogen accumulation in the body tends to increase.
キーワード
Small herbivore
Cecum
Nitrogen metabolism
Cecotrophy
備考
総説 (Review)
発行日
2015-02-01
出版物タイトル
岡山大学農学部学術報告
出版物タイトル(別表記)
Scientific Reports of the Faculty of Agriculture Okayama University
104巻
出版者
岡山大学農学部
出版者(別表記)
Faculty of Agriculture, Okayama University
開始ページ
23
終了ページ
34
ISSN
2186-7755
資料タイプ
紀要論文
言語
Japanese
論文のバージョン
publisher
査読
無し
Eprints Journal Name
srfa