When I had time to hunt, we had a bag of sand that we would pour in the wounds to keep them from bleeding. I would assume that cat litter is just as effective at clotting blood that is no longer being pumped.
As for humans, bleeding from small scrapes and cuts can be stopped by putting pressure on the wound, cleaning with alcohol, and putting a bandaid over it. For larger wounds that don't result in internal injuries but are bleeding rather profusely, QuikClot is a commercial product that the military has been using for about ten years. It isn't very effective in deep puncture wounds or gunshot wounds, but it can clot rather large superficial cuts.
I had an incident of carelessness when I was younger where I managed to stab myself in the thigh (a little above my knee) with a hunting knife. It went in about a good inch or so and bled for about an hour. I lifted my leg up above my heart, pushed some cloth into the wound and put a lot of pressure on the wound. I cleaned it out later that evening and taped it up, and now all I have to show for it is a small scar a little less than an inch wide. This would be an instance where a coagulating agent would be useful to help stop the bleeding.