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
Animal law Animal law Animal law is a combination of statutory and case law in which the nature legal, social or biological of nonhuman animals is an important factor. Animal law encompasses companion animals, wildlife, animals used in entertainment and animals raised for food and research. The emerging field of animal law is often analogized to the environmental law movement because "animal law faces many of the same legal and strategic challenges that environmental law faced in seeking to establish a more secure foothold in the United States and abroad". Animal law issues encompass a broad spectrum of approaches from philosophical explorations