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Maedi-visna is a debilitating viral disease that can undermine the economic viability of a sheep flock.
The name Maedi-Visna is an Icelandic description of the two major forms of the disease (Maedi=progressive pneumonia and Visna=wasting). Although it is ultimately fatal, most of the economic loss attributed to this disease is due to decreased milk production; lowered weaning weights; increased incidence of severe arthritis and wasting; higher than average number of respiratory infections; and decreased ewe fertility. In one study, it was found that 66% of healthy appearing, Maedi-Visna positive ewes had udder lesions and their lambs had lower than average weaning weights. The disease is common in many sheep producing countries, and 70% of flocks tested in Ontario in the late 1980's had at least one positive animal. There is no cure or treatment for the disease, however, there is a reliable blood test that can identify infected animals.
The Ontario Maedi-Visna Flock Status Program (OMVFSP)
The OMVFSP is a voluntary program to enable sheep producers to determine the disease status of their flocks with respect to Maedi Visna infection, and to lower the risk of this infection through a program of biosecurity, serological testing of sheep and subsequent removal of postive animals from the flock.
To enroll in the program, the producer must be willing to follow the protocols of the program, permanently and uniquely identify all sheep in the flock, and follow specific biosecurity requirements.
List of producers enrolled in Ontario Maedi Visna Flock Status Program
- Testing your flock
- Blood is collected by your flock veterinarian and samples are sent to the Animal Health Lab at the University of Guelph at a cost of $14.00 per sample
- Results are sent to Ontario Sheep Farmers (OSF) and OSF then informs you and your vet of your test results
- Protocols Supplementary Information
- Creating a negative MV Flock from Positive Flock Genetics
- Establishing a MV Low Risk Flock from 1st Time Lambing Ewes
- Flock Management to Lower Risk of MVV Infection in Lambs
- Maintaining Flocks of Differing Health Status
- Biosecurity Requirements
- How Maedi Visna Testing Works on the Program - By Dr. Paula Menzies
- What Does Maedi Visna Mean to Your Flock - By Dr. Paula Menzies
- Vimeo Video - Ovine Progressive Pneumonia in Canadian Sheep Flocks, What it Means for Farmers
- The National Sheep Producer Biosecurity Planning Guide
For more information or to enroll in the program
Contact the Ontario Sheep Farmers office
P: 519.836.0043
E: admin@ontariosheep.org