Rumen-stable pellets

Claim 1

In a composition adapted for use in coating pellets orally administrable to a ruminant which protects the core material in the rumen and releases it in the abomasum comprising (a) from about 16 to about 87% based on the total composition weight of a film-forming polymeric material comprising a polymer, copolymer or mixture thereof having a molecular weight of from 5,000 to 300,000, said polymeric material having basic amino groups the nitrogen content of which constitutes between about 2 and about 14% by weight, of the polymeric material. (b) from about 0.5 to about 32%, based on the total composition weight of a hydrophobic material dispersed in said polymeric material selected from the group consisting of waxes, resins, polymers, fatty acids having from 12 to 32 carbon atoms, aluminum salts of fatty acids having from 12 to 32 carbon atoms and polyfunctional carboxylic acids having a ratio of from 10 to 22 carbon atoms per carboxyl group having a molecular weight of from 400 to 1,000, and (c) from about 7 to about 80%, based on the total composition weight, of a flake material dispersed in said polymeric material the improvement comprising, said flake material having a relatively high degree of hydrophobicity due to the flake material having been treated by bringing the flake material into rubbing contact by milling with said hydrophobic material so that the surfaces of the particles of flake material become hydrophobic. said polymeric material in combination with said hydrophobic material and flake material being physiologically acceptable and resistant to a pH of greater than about 5 but capable of releasing the core of the pellets at a pHD of less than about 3.5, said coating having a sticking temperature of at least about 50° C.