I think that particularly anyone who has pets MUST make some arrangements to be found in a "worst case" scenario. This is not about how soon, or how late, your dead body will be found on the floor. It's about simple human decency.
I don't have pets (any more) but have done all I can think of to prevent lying on the floor for days. Here's what I've done:
1. The Lively alarm pendant I wear around my neck. (You can go to lively.com to learn about them, and there are lots of other alarm companies as well.)
2. I set the alarm on my cell phone to ring every morning at the same time. It reminds me to send a short text to my son and daughter. The text is very short, usually just a friendly "Hi!" unless I actually have something to say. We do communicate a lot during the day. But they know they have to get that message from me every morning. If they don't they send me a text asking if everything is all right.
And this part hasn't happened yet, fortunately, but if they get no answer, my son (who lives nearby) would call me on the phone. If no answer, he'd come over. He has a key. Or, if he is out of town, he has the phone number of my next door neighbor, who also has a key for emergencies.
So, I feel reasonably protected. There's no reason to live in fear that you will lie on the floor for days. And for anyone with pets, that is inexcusable. The pets must be part of a "what if" plan, as if they were your children.
P.S. There are other options as well. Some elder organizations provide a service where they call you every day at the same time. If you don't pick up, they send the medics.