Texas Cattle and Big Game Ranchers’ Concerns Mount After Screwworm Detected in Dog South of the Border

South Texas producers remain on alert as screwworm concerns grow; sterile fly efforts underway to prevent spread.

BROOKS COUNTY, Texas (RFD News) — Concern is growing across the American South after reports of New World screwworm being detected in a dog in Monterrey, Mexico. RFD News correspondent Frank McCaffrey spoke with a South Texas veterinarian about what the ag community is doing to stay ahead of the threat.

Dr. Mike Vickers, a veterinarian and rancher in Brooks County, says efforts using sterile flies are showing promise in the fight against the pest.

“I was talking to some Animal Health Commission representatives here just the past couple of days, and they’re releasing screwworms here in South Texas in different locations,” Vickers explains. “They have traps in these areas, and they’re catching some of the sterile flies. They identify them with ultraviolet light, I guess.”

Vickers says those sterile flies are also being released in the Tampico, Mexico area, and so far, there have been no confirmed cases in his part of Texas. Still, concern remains after a recent case surfaced closer to the U.S. border.

“I know there was more recently — a calf showed up about 60 miles from the border with screwworm,” he recalls.

Vickers says his clinic is receiving frequent calls from concerned producers, including livestock and exotic animal owners, and adds that the screwworm could also affect Texas wildlife populations, including deer, javelina, and quail.

“Every day, I get three or four phone calls a day, and it’s not just the livestock, it’s the African plains game, people that raise African plains game,” he continues. “You don’t have to go very far coming up here. You pass by a number of game ranches that are really concerned because of the value of these animals is incredible.”

As concerns grow, Vickers is also offering guidance on how producers can protect their animals.

“Well, we do have some products out that are shown to kill the screw worm,” Vickers says. “DecoMax is one. A new product by Merck has a good killing ability for New World screwworm.”

He adds that ivermectin-treated molasses tubs have been used in Panama and have proven effective.

Frank McCaffrey reporting for RFD News

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RFD NEWS Correspondent Frank McCaffrey covers news from Texas, in the US-Mexico border region. He has provided in-depth coverage of immigration, the 2021 Texas freeze, the arrival of the New World screwworm, and Mexico’s water debt owed under a 1944 treaty.

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