Wearing a grey-felt cowboy hat, long-sleeve ivory-colored shirt and freshly laundered jeans, Dr. Arnoldo Gutierrez begins his daily rounds by walking into a dusty pen baking in the South Texas heat.
"Hey, hey! Let's go!" he hollers. "C'mon, Whitey. Come here, Red."
Gutierrez's "patients," addressed by their color, are more than 100 head of nervous cattle freed from a truck that just arrived from Mexico, crossing the international bridge over the Rio Grande at Laredo.
The U.S. Department of Agriculture veterinarian is looking for obvious signs of lameness, open wounds, appropriate castration and parasites carrying potentially deadly disease.
For years, these inspections have been conducted before cattle cross the border, but the war raging among drug cartels in Mexico has prompted the U.S. to move some of its operations north.
The change, instituted over the past year at three of the 11 ports along the U.S.-Mexico border, is drawing concern from some cattle raisers, who fear infections long eradicated in the U.S. but still showing up in Mexico will spread before inspection.
Federal authorities say the cartel violence necessitated the change, and they have implemented safeguards to ensure that rejected cattle reaching the U.S. won't prompt any outbreaks.
"I think it's fair to say that the facilities located in Mexico presented a wide variety of risks and threats, and our employees did not feel safe going to those facilities every day," said U.S. Agriculture Department spokeswoman Lyndsay Cole.
The drug war has killed more than 34,600 people in Mexico since President Felipe Calderon announced a major offensive against traffickers when he took office in December 2006. Some American civilians and U.S. authorities have been victims of the violence, including a federal immigration agent killed in a roadside ambush in February along a Mexican highway.
Fearing this violence could reach some of their inspection sites farther inside Mexico, U.S. authorities chose to move inspections to the Texas ports at Pharr, Laredo and Eagle Pass. The sites' Mexican inspection counterparts _ outside Reynosa, Nuevo Laredo and Piedras Negras _ were about 20 miles away from the border, while the other eight inspection sites are near or at border crossings.
The change is supposed to be temporary, although there are no immediate plans for the American inspectors to return to Mexico.
Meanwhile, Gutierrez, who lives 500 miles to the north in Aspermont, has been spending a week each month as part of a rotating team of veterinarians at the Laredo inspection station until someone is permanently assigned. Any cattle he rejects is placed in a sealed truck and returned to Mexico, followed by a USDA person to make sure it leaves the country.
"We have many protocols in place to ensure that the temporary facilities inside the U.S. continue to provide the same level of protection against diseases as the facilities in Mexico did," USDA Under Secretary Edward Avalos said.
USDA figures show an average 955,000 cattle and calves were imported from Mexico annually the past three years. Texas last year accounted for more than half the total _ 511,719 feeder steers and spayed heifers, according to the Texas Department of Agriculture.
Discovery of just one feared parasite known as the fever tick outside a traditional border-wide quarantine zone in Texas from Brownsville to Del Rio could cost the multi-billion-dollar Texas cattle industry an estimated $123 million the first year alone, a 2010 study by the Texas A&M University Agricultural and Food Policy Center estimates.
The ticks cause what's known as Texas Cattle Fever, which results in slow or low growth, reduced reproduction ability and death. In the past, the illness has spread among cattle beyond Texas and into parts of the Midwest, East Coast and even California.
Any infestation that reaches American herds would require an expensive process in which animals are walked through a pesticide bath like one the Mexican cattle are immersed in at the Laredo inspection station before they head to U.S. feedlots. A rancher with infected cattle would have to dip his entire herd from the pasture where the infected animal grazed _ a process repeated every two weeks for nine months _ at a cost of at least $150 per head.
"All that is lost money," said Ty Keeling, a rancher from Pleasanton, about a half-hour drive south of San Antonio.
Keeling, 30, gets his cattle from Mexico but no longer travels there for safety reasons. He understands why the inspections were being moved to Texas but fears state and federal budget cuts could lead to reduced inspections.
"It's a national issue if not controlled at the border," Keeling said. "If you had an outbreak that covered the whole southern part of the United States, that would eliminate a lot of cattle numbers _ and drive up the price of beef."
At the Laredo site, Gutierrez's inspection includes scratching each animal's hide to check for a tick infestation, a seemingly innocuous exercise that turns dicey as he sticks his arm between the steel bars of a narrow chute to get his hand on a clearly unhappy steer.
If the animal bucks, the doctor's arm could be snapped between the bars and the animal. A quick move by the steer means Gutierrez must be quicker to jerk his arm back out of harm's way.
"I've just been lucky," he said of avoiding injury. "It's not a question of if, but when."
Before shipment to the United States, animals are scrutinized by Mexican authorities, who mark the truck with a numbered seal that's matched to paperwork accompanying the animals once they reach the Laredo inspection, Avalos said.
On this day, it's apparent the animals have been seen by the Mexican agricultural inspectors, Gutierrez said. Only one is returned, for a faulty castration.
"This cattle is coming in pretty clean," said Gutierrez, his shirt and hat now spotted with cattle excretions. "They do the best they can."