In this Tuesday, Dec. 27, 2016, photo, Trooper Mike Wilson of the Ohio State Highway Patrol leads his drug-sniffing dog partner "Pluto," a Dutch shepherd, past a truck stopped on I-70 in Madison County, Ohio. The patrol has doubled the number of K-9 units to 34 in recent years as part of its efforts to find more drugs as Ohio battles an unprecedented number of overdose deaths.