Ovine Progressive Pneumonia
Ovine progressive pneumonia (OPP) is a slowly progressive viral disease that affects nearly half of all Minnesota sheep flocks and results in reduced profits. Caprine arthritis-encephalitis (CAE) is a similar disease of goats. Common early signs are a general loss of body condition and labored breathing or coughing while at rest. The virus can also cause “hard bag,” an enlarged, firm udder with little or no milk flow, as well as swollen joints and lameness. Once infected, animals remain so for life though many will never exhibit clinical signs of disease. There is no vaccine or cure, and standard eradication methods involve costly rigid culling of test-positive animals and/or orphan rearing of young stock. Minnesota is currently trialing a less expensive eradication method.
OPP Pilot Program
In 2006 the Minnesota Board of Animal Health introduced a voluntary OPP Test and Control program. Originally offered as an optional add-on component of USDA’s voluntary Scrapie Flock Certification Program, the pilot is now a stand-alone program and any flock/herd in Minnesota is eligible to apply.
OPP Eradication Trial
In 2013, an OPP Eradication Trial was initiated as part of the pilot program, with selected producers testing an alternative eradication strategy based on recent research findings. This trial is a collaborative effort of the Minnesota Lamb & Wool Producers Association, the University of Minnesota Veterinary Diagnostic Laboratory and College of Veterinary Medicine, USDA APHIS Veterinary Services, and the Board of Animal Health. Applications are no longer being accepted for the trial, but the method being studied can be applied in any flock and is described in one of the files linked below.