The California Highway Patrol reported that the two-vehicle crash occurred on Highway 29 near the Napa County line just after 7:30 p.m.
One vehicle was off the side of the road, with traffic backing up, the CHP said. Animal Care and Control was summoned to help with a domestic pig.
The CHP requested one of its Santa Rosa units respond to Santa Rosa Memorial Hospital to pick up a blood sample.
The roadway was reopened just before 9:30 p.m., the CHP said.
Additional details, including the names of those involved, was not available Friday night.
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