Effect of 1,2-propanediol on the rumen mucosal growth of kids.

Intra-abomasally administered 1,2-propanediol, 150 to 160 g per Japanese meat-type kid in 3 to 4 wk, increased the ratio of rumen to body weight, of rumen to total stomach, and of rumen mucosa to muscle over the control which received only water. Intra-abomasal administration of glycerol, glucose, fructose, 1.3-butanediol, xylitol, lactic acid, sodium propionate, or sodium butyrate showed no increases over the control. Only propanediol chemically stimulated rumen mucosal growth. Intraruminal administration of propanediol showed the same stimulation as intra-abomasal. Intraruminal administration of minerals or of polyethylene glycol (Carbowax 4,000) and intraruminal insertion of plastic cubes were not effective, but the latter showed a cooperative effect to accelerate rumen growth with propanediol stimulation. Average fresh tissue weights of rumen mucosa in kids of 2.7 kg body weight of control, of propanediol-treatment, and of plastic cube plus propanediol-treatment were 6.4, 10.4, and 14.8 g, and those of rumen muscle were 7.9, 8.3, and 11.1 g. Propanediol may be involved directly in the local control of rumen epithelial growth.