In my freshman biology class we dissected a cat. I was given a great big fat old long hair black cat. Yuck! Black hair everywhere. It was a male, they said, but darned if I could find any sexual organs. I'm guessing it was a pet cat that was scooped up and dispatched. The companies who supplied animals did that all the time.
Who knows how the cats were gathered and dispatched. Maybe some family still looking for Fluffy even as he was laid out on my dissecting tray. Didn't make me happy then, doesn't make me happy now.