Maedi-visna in Canadian sheep

Area of Science:

• Veterinary Pathology
• Ovine Virology
• Immunology

Background:

• Maedi-visna is a progressive, debilitating disease affecting sheep worldwide.
• It is caused by a lentivirus that targets the immune system and central nervous system.
• Previous outbreaks have impacted sheep populations, necessitating diagnostic efforts.

Purpose of the Study:

• To report the initial findings of maedi-visna in a specific research flock.
• To confirm the presence of maedi-visna through laboratory diagnostics.
• To lay the groundwork for future epidemiological studies within the affected flock.

Main Methods:

• Gross and microscopic examination of affected sheep tissues.
• Isolation and identification of viral particles using electron microscopy.
• Serological testing to detect antibodies against the maedi-visna virus.

Main Results:

• Histopathological lesions consistent with maedi-visna were observed in sheep.
• Viral particles characteristic of lentiviruses were visualized via electron microscopy.
• Serological assays confirmed the presence of antibodies, indicating infection.

Conclusions:

• The diagnosis of maedi-visna was confirmed in the Animal Research Institute's sheep flock.
• Further investigation is warranted to understand the full extent of the disease in this population.
• These findings highlight the importance of ongoing surveillance for ovine lentiviruses.