Rio Grande City, TX (KRGV) — Cattle ranchers in Starr County are taking steps to protect their cattle against the New World screwworm after three confirmed cases, including two that are active.

Arturo Gonzalez has been ranching in Starr County for 50 years. He worked 31 years with the United States Department of Agriculture and helped fight the fever tick in cattle.

Now retired, Gonzalez is dealing with the New World screwworm at his ranch in Rio Grande City. 

To keep flies off his 25 cattle, he uses a solution called Vernecrin, a fly repellent for animals that lasts about a month. 

"I like to do it because I want to protect my cows," Gonzalez said.

Gonzalez spent about $200 to hire someone to use the spray on his cattle.

"That wouldn't be the last time I do it," Gonzalez said.

Joseph "Romeo" Ozuna is with the Western Starr County Ranchers Association. He has been asking ranchers to speak up if they see a screwworm infection in their animals and call the Texas Animal Health Commission.

"The cattle industry, it provides finances," Ozuna said. "If you suspect anything, give your proper agencies a call."

Gonzalez says the cost will add up over time, but he does not plan to stop until the screwworm is eradicated.

Once Gonzalez starts seeing flies on his cattle again, he plans to spray them again.

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