Ovine pulmonary adenocarcinoma Ovine pulmonary adenocarcinoma Ovine pulmonary adenocarcinoma (OPA), also known as ovine pulmonary adenomatosis, or jaagsiekte, is a chronic and contagious disease of the lungs of sheep and goats. OPA is caused by a retrovirus called jaagsiekte sheep retrovirus (JSRV). The disease has a long incubation period, and therefore signs usually occur in adult animals (over 2 years of age). Clinical signs resemble a non-specific progressive pneumonia, including poor body condition and, particularly after exercise, respiratory difficulty. Unless a concurrent lung infection is present, affected sheep continue to eat. The only sign specific to OPA is a watery nasal discharge, consisting
Center for Alternatives to Animal Testing effect change by working with scientists in industry, government, and academia to find new ways to replace animals with non-animal methods, reduce the numbers of animals necessary, or refine methods to make them less painful or stressful to the animals involved. CAAT also operates Altweb, a global clearinghouse for information on alternatives to animal testing, and publishes a general animal news blog, A Boundless Ethic. Center for Alternatives to Animal Testing The Johns Hopkins University Center for Alternatives to Animal Testing (CAAT) has worked with scientists since 1981 to find new methods to replace the use of laboratory animals in