Found worm-like things in my brisket flat. Anyone else ever find these?

I was trimming a brisket to smoke tomorrow and as I'm trimming fat off the flat I pulled these out: https://imgur.com/gallery/1qZEb. The dark one looks sort of like a worm, and the pink one was full of a dark liquid that I think may have been blood. The pink one was also firmly attached.

I think both of these may just be a vein/artery or something, and not a parasite. But I've never come across this while cooking anything else so I wanted to check here. Has anyone else seen these and been fine? Realllly don't feel like going to get another brisket tonight