rat small intestine 82%: rat colon 71%: mouse small intestine 74%: mouse colon 67% w/w
||McConnell EL, Basit AW, Murdan S. Measurements of rat and mouse gastrointestinal pH, fluid and lymphoid tissue, and implications for in-vivo experiments. J Pharm Pharmacol. 2008 Jan60(1):63-70. p.67 left column top paragraphPubMed ID18088506
||"To determine the gastrointestinal water and solid contents,
the wet mass of the section contents was recorded, followed
by lyophilization (Virtis-Advantage Freeze Drying Apparatus,
Virtis, UK), measurement of the dry mass and calculation
of water content."
the water concentration decreased along the length of the gastrointestinal
tract from 82% w/w of the small intestinal
contents to 71% w/w in the colon in rats, and from 74 to 67%
w/w along the same segments in mice. The decreasing water
content was observed visually as an increase in the viscosity
of the gastrointestinal contents."