The cattle crossing between Douglas, Ariz., and Agua Prieta, Mexico, might not look much different since it reopened in late August.

The pens, the buildings — they’re all still there.

But new protocols and procedures are happening within them that could redefine how cattle move between the two countries.

Douglas port has many eyes on cattle

The U.S. government initially closed all Mexican border ports to livestock in May 2025, saying it was necessary to reduce the risk of New World Screwworm spread.

The pest has been detected in nearly 43,000 animals in Mexico since late 2024.

But the closure exacerbated cattle shortages that have pushed American beef prices to record highs.

And pressure to reopen the border accelerated as screwworm cases were confirmed in Texas and New Mexico.

The United States Department of Agriculture (USDA) chose to reopen the Douglas port first because of the proactive response that the Mexican state of Sonora has taken to counter the pest.

Officials announced a slew of new requirements to move cattle from Sonora into the U.S., including multiple inspections and an electronic ear tag for tracking each animal’s health and point of origin.

“It really is unprecedented,” said Arizona Department of Agriculture Animal Services Division Director Rob Smook, who has embedded state inspectors at the Douglas site.

From dogs to ear tags, much is new

Only heifers and steers that hail from Sonora are accepted at the port. A certified veterinarian must examine them days before transport.

Once at the port, the Agua Prieta side of the facility now separates new arrivals from those that have already begun their health inspections.

Newly trained dogs patrol for the trademark smell of screwworm larvae.

Cattle are funneled first to inspectors from SENASICA — the Mexican agency in charge of livestock health — and then to USDA veterinarians.

Those that pass these multiple layers of inspections are dipped in a pool of insecticide before they are allowed to cross into Douglas.

Once across the border wall, cattle are sorted and run through a newly installed scanner to check health records on their ear tags.

Electronic tags are now required in the ear of every heifer or steer that arrives at the port.

Meaning that, for the first time, buyers, sellers and port officials can track where animals have been, in real time, with multiple health records at their fingertips.

It offers a new level of traceability that Smook believes will quickly become the standard, whether cattle are imported or not.

Sonoran officials want redundancy

About 20,000 heifers and steers have passed through the Douglas port since it reopened on Aug. 24, according to port officials.

The process is rigorous, and some cattle are losing as much as 8% of their body weight in the movement, said Jose Morales of the Unión Ganadera Regional de Sonora, the Sonoran cattle union that operates the port.

Union officials are looking for ways to make the process easier and less stressful. They are adding additional pens.

And they are lobbying heavily to reopen the Nogales, Ariz., crossing.

A confirmed screwworm case could shut down ports for at least 90 days, a delay that many ranchers can no longer wait out.

“We need two ports open in Arizona,” Morales, who owns a ranch about 25 miles south of the border, said. “If so, we can get through this backlog in less than a year.

“If not, our cattle will have to be sold in Mexico. They’re so big now. We don’t have much choice.”

Prolonged closures could change things

Before the closure, Sonoran ranchers typically raised cattle until they were 400 to 700 pounds.

Then they sold them to feedlots in states such as Arizona, Texas and Oklahoma, where it was cheaper to fatten cattle on corn, hay and other feed.

Mexican ranchers could raise more cattle by exporting them to a larger market than what they could sell domestically.

And American processors benefited from a steady supply, even if the imports only accounted for about 5% of our nation’s beef.

After 15 unexpected months on Sonoran rangeland, the cattle now being imported are so big that they’re nearly ready for slaughter.

If ranchers there begin sending those cattle to Sonoran processors and finishers because of backlogs or closures, it could add unexpected twists to an already complex binational food system.

“At the end of the day, it’s all a chain,” said Juan Villalobos, who manages the Douglas port. “We are all closely linked.”


Joanna Allhands writes about water, land use and other issues important to the Arizona Farm Bureau. Reach her at joannaallhands@azfb.org.