FORT WORTH — About 28 head of cattle bound for the Panhandle were killed or fatally injured Wednesday when a tractor-trailer overturned before dawn on a freeway ramp near downtown.The wreckage snarled traffic on three freeways for most of the day while crews worked first to recover surviving animals. The wreckage was finally cleared about 4 p.m.Ninety-five head of cattle — most appeared to be calves — were in the truck when it tilted and fell on its side about 3:30 a.m. on a curving ramp from U.S. 287 to northbound Interstate 35W. Animals were pulled one by one from the wreckage. “The cows were still inside the trailer, so there was no mass roundup,” said Terry Grisham, a Tarrant County Sheriff’s Department spokesman. “While the wreck itself was bad enough for traffic, there was no roaming livestock.”Fence panels were set up leading from the back of the trailer to contain the animals after they were pulled from the overturned trailer.About 60 head were taken to a pasture leased by Tarrant County between Fort Worth and Saginaw.“They collected 21 carcasses at the scene,” Grisham said. “Two more died at the pasture.”Grisham added that two more cows “were in distress” at the pasture and might not survive. Another “four to seven” carcasses were still tangled in the wreckage when the truck was towed from the scene.Fort Worth police and firefighters, Tarrant County sheriff’s deputies, crews from the state Transportation Department and other agencies worked to rescue the animals and clear the highways.The sheriff’s deputies were part of a special department unit — the Livestock Estray Enforcement Program or “LEEP.”Members of the unit are equipped and trained to round up loose livestock. They keep horses, trailers and other materials such as portable fence panels at county facilities, ready to respond to livestock calls anywhere in the county, Grisham said.“Working in unincorporated areas, we get stray-livestock calls frequently,” Grisham said. “That’s standard cowboy procedure for us.” But the task Wednesday was unusual, Grisham said, because LEEP deputies typically deal with smaller numbers of livestock.The truck driver, Jesse Rubio, told WFAA TV that he was heading to Shamrock in the Panhandle when he lost control of his truck on the ramp. He said he was not speeding. The owner of the truck was Barboza Trucking of Kansas, police said.“I was really lucky I did not flip over,” Rubio told WFAA. “I could have died.”Rubio had minor injuries, police said.Grisham did not know who owns the cattle or who employs Rubio. Fort Worth police said more information will be available Thursday. Traffic on three freeways around downtown Fort Worth was at a standstill during the morning commute and crawled all day. Police redirected northbound U.S. 287 traffic to I-30 westbound, where motorists could exit to northbound I-35W.Missy Bonds, assistant manager of Bonds Ranch north of Saginaw, said the cattle were likely shy of slaughter weight because of the number aboard the trailer. She speculated that they were heading to summer pasture. If they weighed about 600 pounds each, they could be worth around $1,000 a head, Bonds said. Staff writers Barry Shlachter and Domingo Ramirez Jr. contributed to this report.