| abstract |
An imidazoline modified styrene-acrylonitrile polymer composition which is substantially insoluble in aqueous media at about pH 6 or more but swellable or soluble at pH 3 or less is employed as a coating for nutrient or therapeutic substances for administration to ruminants. The substances thus are rendered resistant to attack and breakdown in the rumen yet remain susceptible to release and digestion within the abomasum or small intestine of the animal. |