Feed grinders can crush a variety of special feed materials. For example, various crop straws, such as corn straws, wheat straws, etc.; various forage grasses, such as alfalfa, silage corn, etc.; and some unconventional feed materials, such as tofu residues, distiller's grains, etc. However, it should be noted that different special materials may require adjustment of the grinder parameters, such as screen aperture, speed, etc., to achieve a better crushing effect. For example, when crushing silage corn, it may be necessary to appropriately increase the screen aperture to avoid excessive crushing.