Abstract: Synthetic polymer compositions such as polymers and copolymers of ethylene and an alpha-olefin having a tensile strength at yield of less than about 1500 psi, a hardness of less than about 40 units on the Shore D hardness scale, and a tensile strength at 300% elongation of between about 450 to 1200 psi are effective artificial roughage materials when fed to ruminant animals. These synthetic polymer compositions, when ingested by the ruminant, form a loose fibrous mass in the rumen of the animal which enhances rumination. Increasing the rumination results in increasing the consumption of the feed by the animal and thus results in increased production of the animal products.