SCRUBGRASS TWP, Venango County — A portion of Interstate 80 was a scene of udder gridlock Thursday night as a small herd of dairy cows escaped an overturned trailer and hoofed it down the highway near the Venango-Butler county line.

The cattle call shortly before 6:30 p.m. near the Emlenton Bridge proved challenging for police and firefighters tasked with coaxing and corralling the dozens of, at times, bullheaded bovines.

Westward traffic was finally restored six hours later, authorities said, but not before an animal control officer had to help end the cow-tastrophe.

“It was funny at first,” said Barry Louise, assistant fire chief for the Emlenton Volunteer Fire Department, “but then we all got tired of doing it.”

The impromptu roundup began after a double-decker cattle truck hauling 30 cows tipped over on its driver’s side while traveling west on I-80 in Scrubgrass Township. Some of the cows made a break for it; some remained on the 50-foot-long trailer.

Five of the cows died in the crash or had to be euthanized due to injuries they suffered.

The driver, James Gambrel of Ohio, suffered minor injuries. State police did not know what caused the wreck.

According to emergency crews, the driver claimed another vehicle forced him off the road. The truck’s cab eventually ignited in fire.

Police at once shut down traffic in both directions at the scene. Emlenton firefighters were called in to aid in the cattle maneuvers and to put out the vehicle fire.

“As we were coming on scene,” Louise said, “we saw several cows running up the westbound lanes. They got off the concrete pavement pretty quick and headed for the grass median and the sides of the highway.”

In all, 10 to 15 cows were on the loose. Two were still missing this morning. They were last seen on Squaw Valley Road, Allegheny Township, about a mile from the crash site.

Most of them made it past the cement barrier on the bridge and crossed into the eastbound lanes by way of the median.

It soon became clear that more manpower was needed to wrangle up the little doggies.

“They were scared and running all over the place,” Louise said.

Fifteen minutes after the initial call, police requested help from the Venango County Response Team.

Next, troopers at the Clarion station, assigned to patrol the interstate just outside Emlenton, called their colleagues from the Franklin barracks to help.

It didn’t take much longer before state Department of Transportation officials and more firefighters — from departments in Clintonville, Parker and St. Petersburg — were asked to assist as cow catchers and with traffic control.

The Marion Township Volunteer Fire Department was placed on standby at its station in Butler County.

The makeshift drovers, which included seven or eight troopers and 30 or so firefighters, still had not gotten the upper hand by 8:30 p.m. when PennDOT decided to expand the lane closures.

“That was due to the heavy backlog of traffic,” Louise said. “They closed traffic from Barkeyville to Shippenville, 15 miles on each side.”

During the roundup, fire crews parked their engines and rescue trucks around the cows to form improvised corrals to cajole them into a series of trailers provided by Hovis Towing in Emlenton and Hirsch Meats near Knox.

Westbound lanes did not reopen until about 12:40 a.m. today.

Police this morning did not say if the driver would face any moving violations.

All this caused Emlenton to experience a lot of extra traffic.

Borough manager Nancy Marano said the main roads in the borough were backed up for hours, and 90 percent of the vehicles were tractor trailers.

“It was just bumper to bumper as far as I could see,” Marano said.

She said it appeared many vehicles were getting off at I-80 exits 42 and 45 — which bypass the borough. The roads directly off the interstate are windy and hilly, slowing down the trucks.

Additionally, to continue on Route 208 to make it back on the highway, vehicles have to make tight turns at intersections and cross a bridge, further slowing traffic down. She said vehicles generally moved at a snail’s pace and sometimes were stopped for minutes at a time.

Marano said seeing miles of headlights and brake lights was cool, but she also had concerns about how much weight the Route 208 bridge crossing the Allegheny River could hold.

She said this morning that several cars along roads in the town reported damage.

Around midnight, Marano said some of the trucks began to honk their horns. With the borough in a valley, she said the honking echoed loudly,

Eagle staff writer John Bojarski contributed to this report.