The second possibility is that it is caused by parasites. If the dog ate well two days ago and suddenly stopped eating inexplicably, and his hair became thick and thin, then there is a great possibility of parasites. It often appears in dogs that eat raw and cold meat. In this case, it is generally recommended that dogs do insect repellent regularly.
The third possibility is anorexia caused by diseases in the body. In most cases, it is an infectious disease. At this time, parents must take the dog to the hospital to solve it. It is usually treated by infusion.