An injection molding method to form a pet chew article, comprising providing an injection mold including at least one molding cavity; providing a first polymer composition having a first color; providing a second polymer composition having a second color; plasticizing the first polymer composition in a first plasticizing injection unit; plasticizing the second polymer composition in a second plasticizing injection unit; injecting the first polymer composition and the second polymer composition into the at least one molding cavity such that the first polymer composition and the second polymer composition mix and form a heterogeneous mixture; and forming the pet chew article from the heterogeneous mixture of the first polymer composition and the second polymer composition such that an outer surface of the pet chew article is variegated, wherein the variegated outer surface is formed of a plurality of regions with each region having a different color.
