Proper Diagnosis A PCV2 Challenge
In a PMWS surveillance study sponsored by the National Pork Board, 10 veterinarians submitted a specified set of tissues from a total of 100 cases that they felt fit the description of PMWS
All cases were scored for severity of lymphoid lesions and thoroughly tested for a wide range of viral and bacterial pathogens. PCV2 isolates from selected cases were further characterized geneti-cally. Results of the surveillance showed: • Of the 100 cases, 54 had PMWS and 39 of the 54, or 72 percent, had concurrent PRRS. • Of the 100 cases, 46 had no or mild lesions in the lymphoid tissues associated with PCV2 infection and 56 percent of these had concurrent PRRS. • Twenty-eight of the 100 cases had no evidence of PCV2 infection. • The survey highlights the need for micro-scopic examination confi rming PMWS.
“The take-home message here is PCV2 cases are easy to misdiagnose,” points out John Kolb, DVM, senior biologics manager for Boehringer Ingelheim Vetmedica, Inc. “Th ere are a lot of reasons why pigs don’t gain weight. We have to be careful with this thing and do the diagnostics correctly.”
As an aside, the Pork Checkoff has designated $220,000 for PMWS research in 2006. Funds are being invested to create a producer handbook on PMWS and support research at the following institutions: Western College of Veterinary Medi-cine at the University of Saskatchewan; Kansas State University; Iowa State University College of Veterinary Medicine; University of Minnesota; Virginia-Maryland Regional College of Veteri-nary Medicine; and the Virginia Polytechnic Institute and State University.