Polioencephalomalacia diagnosed in necropsied cattle in Korea

Polioencephalomalacia (PEM) is a neurologic disease of ruminants diagnosed by pathological approach. There is very little information available to understand bovine PEM in Korea. In this study, we investigated the diagnostic rate and pathological features of PEM in 334 necropsied cases of cattle submitted to the Animal and Plant Quarantine Agency in Korea from 2015~2017. PEM was diagnosed only in 13 (3.9%) Hanwoo, the Korean native cattle, and sporadically occurred in our country. The disease was the most diagnosed in fall season, and the age of the cows ranged from 1 month to 3 year. In all PEM cases, softening, and yellow discoloration of the gray matter in the cerebrum and fluorescence at the sites using ultraviolet illumination were grossly observed. Microscopically abundance of glial cells with vacuolar large cytoplasm and neuronal necrosis were commonly observed. This study suggests that future studies are necessary to identify the cause and pathogenesis for the control of PEM in our country.