I used to hitchhike, and one day, got a ride with a trucker hauling blackened animal organs to be turned into pet food (they were blackened as a mark to show they were unfit for human consumption at the place where they were mass harvested). It was the worst smell I've ever smelled in my entire life. I remember gagging for a few minutes as the driver laughed and told me what the deal was.

Still not the worst road story I have lol.

But be aware of what your pet's food is made from. Or make your own, if you're worried about it!

There's typically warning against eating pet food on the bags for that very reason.