An accident involving a big rig truck hauling chickens caused a partial closure to Highway 99 in Turlock Friday morning.

The driver of the big rig, Mayra Alejandre, 23, of Turlock, was not injured in the crash. California Highway Patrol spokesperson Officer Eric Parsons said there were a number of chickens killed and injured in the crash, though the exact amount was unknown.

The accident occurred shortly before 4 a.m. Friday in a northbound lane of Highway 99, near the Lander Avenue exit.

Alejandre was driving a 2007 Freightliner Two Axle Truck for Mings Poultry Inc. out of San Francisco.

For an unknown reason Alejandre made an unsafe turn that caused the big rig to overturn, Parsons said.

A witness told the CHP that the truck had been weaving for several miles. Fatigue and driving under the influence of alcohol or drugs were not factors in the collision, Parsons said.

The overturned truck spilled chicken cages across the northbound lanes of the highway, prompting a closure that lasted about 90 minutes.