OPP Trial new directions on caprine Arthritis encephalitis Virus / ovine Progressive Pneumonia Virus serology

Caprine Arthritis Encephalitis virus (CAEV) and Maedi-Visna virus/Ovine Progressive Pneumonia virus (MVV/ OPPV) are genetically and antigenically closely related. These viruses are transmitted from infected adults to younger animals via respiratory secretions and, to a lesser extent, from dam to kids/lambs via colostrum and milk. Historically the control strategies for these diseases have centered on serologically testing animals followed by culling or by segregating positive animals and orphaning newborns. Among tests available to identify positive animals, ELISA and AGID are the most commonly used serological tests. Various commercial ELISA test kits are available for the detection of antibodies to CAEV/MVV/ OPPV. Three separate sheep flocks have experienced cross-reactivity to cELISA and AGID possibly due to recent use of chlamydia bacterin for abortion control. This presentation describes the use of “Elitest” ELISA for detection of antibodies to CAEV/MVV/OPPV. This test was used to confirm and eliminate this cross-reactivity and is now being used in an OPPV Eradication Trial in collaboration with the USDA, MN Board of Animal Health, MN Lamb and Wool Producers, and the MN Veterinary Diagnostic Laboratory and College of Veterinary Medicine.