Few things are more frustrating for a cattle rancher than losing livestock to disease.

But it’s double the headache when a cow dies for reasons unknown. Unfortunately for producers and their veterinarians, mysterious deaths seem more common lately.

That’s according to Russ Daly, state public health veterinarian with South Dakota State University. He told Farm Forum in a phone interview that livestock vets are noticing more cows coming to their clinics with symptoms similar to the often-fatal Johne’s disease, an infection often found in the small intestine.

On the surface, that seems simple enough. But once those cattle end up on the operating table, some veterinarians are finding an entirely different — and disturbing — issue: plastic.

Bale net wrap can be deadly to cows

Some vets are finding wads, clumps and globs of plastic in the stomachs of cattle, Daly said. The foreign bodies vary in shape and size: some are stringy strands of ground plastic as long as 12 inches, while others are large wads about the size of a basketball and weigh around 1 to 2 pounds.

A large clump of plastic net wrap removed from a cow's stomach lies on the ground. Russ Daly, state public health veterinarian with South Dakota State University, said he has noticed more producers taking their sick livestock to diagnostic labs over the years, and cases in which significant amounts of plastic are found in their digestive systems are becoming more common.

According to Olivia Amundson, cow/calf field specialist with SDSU Extension, the problem stems from net wrap, a plastic covering that farmers use to organize piles of hay. The material is literally wrapped around the feed using a baler, which is what gives hay bales their iconic circular-shape. 

“The big thing is guys just don’t remove net wrap,” Amundson said.

“Leave net wrap on a bale and the cows will get into it because cows get curious and will eat anything. I’ve seen cows munching on net wrap. You just know that’s probably not the best for them,” she said.