The semi went off the right side of the ramp and struck the bridge support for the Diamond Mill overpass before overturning, the patrol reported.
The driver was taken to Miami Valley Hospital with serious injuries.
The semi was transporting approximately 200 pigs from Rossburg in Darke County to Louisville, Kentucky. Dull Homestead Inc. responded to help with the pigs, which were contained to the crash site.
The ramp was closed following the crash and reopened just before 2 p.m., the patrol said.
The Ohio Department of Transportation, Clay Twp. Police Department, Englewood Fire/EMS, Brookville Fire/EMS and Englewood Towing also assisted at the scene.
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