These dogs usually have a mostly white coat and blue irises, and are often deaf, blind, or both. In this case, the deafness and blindness are linked to having two copies of the merle gene, which disrupts pigmentation and produces these health defects.All black and blue merle dogs have black noses, eye rims, and lips. All red and red merle dogs have liver or brown noses, eye rims, and lips. The recommended amount of food an Australian Shepherd should eat is 1-1/2 to 2 cups of dry food a day, But size, exercise level, and age should be considered. With proper diet and exercise, the Australian Shepherd can stay in good shape.