Compositions, methods of preparing compositions, and methods of treating parasitic nematode infections in wild birds include a fenbendazole premix and a grain formulation. The fenbendazole premix includes fenbendazole, a solvent, a solubilizing agent, and a premix grain carrier. The grain formulation includes a plurality of grains selected from the group consisting of ground corn, soybean meal, whole milo, wheat midds, and rice bran. The fenbendazole premix is integrated within the grain formulation thereby yielding a fenbendazole concentration in the composition of between 80 ppm and 120 ppm. Processes and methods of preparation include mixing the fenbendazole premix and grain formulation in an industrial ribbon mixer, fully integrating the fenbendazole within the grain formulation. Methods of treating include collecting and testing samples, determining a number and location of treatment systems, and charging a feeder with the claimed composition.
