'Dual Survival' Star Joe Teti -- Attacks Dog Over Cat-astrophe

One of the stars of Discovery's "Dual Survival" injured or killed a dog on the set during the final episode ... this according to multiple sources connected with the production.

Our sources say Joe Teti, a former Green Beret, was shooting one of the final scenes when some stray cats ran across the set ... apparently fleeing from a dog. We're told the dog actually got one of the cats in its jaws, and that's when Teti went after the canine.

We can't get a straight story from the various sources, although everyone agrees at the very least Teti injured the dog while saving the cat. But some of the sources say he killed the animal.

One source says Teti has been a problem in the past, but they say it's not limited to him. As one source put it, "These survivalists all have a screw loose."

The show had already been cancelled, and we're told the dog incident made people at Discovery feel even more comfortable about their decision to pull the plug.