What is going on when the gray swallow tail hair is falling

The gray tail tail is hairy.In addition to changing hair, when the bird gets sick, it will also cause the tail to lose hair.If it is because of changing hair, do not need to worry too much, as long as you do a good job of sanitary work, the birds will grow new hair by themselves.However, if it is sick, it is usually skin disease or infected with parasites. This requires observation and understanding the cause, and then make corresponding treatment methods according to different diseases.