Ovine pulmonary adenocarcinoma be predisposed to OPA. Most affected sheep show signs at 2 to 4 years of age. OPA is not a notifiable disease, and therefore it is difficult to assess its prevalence. OPA was first described in the UK in 1888, and described in detail in South Africa in 1891. The disease was initially known as "jaagsiekte" , a word derived from Afrikaans, meaning "chasing sickness," so called because animals are in respiratory distress as if they are out of breath from being chased. It has also been known as sheep pulmonary adenomatosis and ovine pulmonary carcinoma. OPA has been used
Title (animal) Title (animal) In animal husbandry and animal fancy, animals can compete in various shows and sports for titles signifying excellence. These titles vary depending on the species of the animal, the kind of show, and the country the event is held in. Dogs competing in conformation shows are eligible to win two titles. The first is best of breed, which signifies that a given animal is the best of its breed at the show. These best of breed winners then compete to win best in show. Animals that win enough best of breeds and best of shows are called "Champions",