Pulled my beef roast out of the slow cooker and saw these weird white stringy things poking out of the meat. They look like little worms or parasites. Is the meat infested?

which are known for their high connective tissue content. These stringy appearances are a natural result of the cooking process and are not indicative of spoilage or infestation.
3. What Slow Cooking Does To Meat Structure
Slow cooking is a method that uses low temperatures over a prolonged period to break down tough fibers and connective tissues in meat. This process transforms collagen into gelatin, which gives the meat a tender texture and rich flavor.
As the collagen breaks down, it can sometimes create white stringy appearances on the surface