Immune system or the use of immunosuppressive medication. In contrast, autoimmunity results from a hyperactive immune system attacking normal tissues as if they were foreign organisms. Common autoimmune diseases include Hashimoto's thyroiditis, rheumatoid arthritis, diabetes mellitus type 1, and systemic lupus erythematosus. Immunology covers the study of all aspects of the immune system. Immunology is a science that examines the structure and function of the immune system. It originates from medicine and early studies on the causes of immunity to disease. The earliest known reference to immunity was during the plague of Athens in 430 BC. Thucydides noted that people who had
Avian immune system The cause is believed to be high exposure to UV rays. Additionally, a cancer of the connective tissue, known as fibrosarcoma, is often seen in the leg or wing. This occurs in many parrot species, cockatiels, macaws and budgerigars. Treatment options include amputation and surgery. Avian immune system The avian immune system refers to the system of biological structures and cellular processes that protects birds from disease. The avian immune system resembles that of mammals since both evolved from a common reptilian ancestor and have inherited many commonalities. They have also developed a number of different strategies that are unique