The heat is causing problems for cattle ranchers across the Rio Grande Valley.

England Cattle Company breeder Benton England said this summer is one of the toughest ever out on the pasture for south Texas ranchers and their cattle.

“With this intense heat that we've been having, cattle are out here grazing in the open sun. That's leading to problems that's affecting their health and the bottom line of ranchers,” England said.

Globally, it's the hottest month ever in history. A cow’s tolerance to the heat has to do with their hide, as the darker cows absorb more of it. 

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Dr. Jack Valerius with Rio Rico Veterinary Services in Mercedes said he’s seen at least six cattle and taken at least ten calls involving cattle with heat related issues.

“By far, double or triple what I’ve experienced in my 45 years in the valley as a veterinarian,” Valerius said. “It’s been one of the toughest spells of bad weather that I know of in my lifetime, especially the animals that are black or real dark keep absorbing more heat. We have some that are real stressed."

Valerius says ranchers need to do what they can to make more shade for their cattle, and add fans if possible.

Out on working pastures, there's a concern that the constant heat will cause the cattle to retreat to the shade, away from the grass they need to put on calories and protein.

“If your cattle are underneath a shade tree, and they're getting skinny because they don't want to go graze, they're going to get skinny,” Benton said. “Then they're not going to produce milk for that calf. And then if they're skinny they're also not going to cycle and get bred back to have another calf next year."

That may be a problem going into the winter, when grass grows slower.

Ranchers are hoping for some relief from the heat for their cattle.