What’s on my beef?

I got these short ribs from BJs and when I went to marinated them they have a bunch of these hair like fibers on lots of the slices. I never seen this before and was wondering if this is normal and if so, what is it? It kind of reminds me of the hairs that you find when cleaning muscles, except white and a little thicker. It comes off easy but I want to make sure the meat isn’t bad and it’s ok to eat.