country insurance, has a policy that we use on our cattle and sheep- on the upper end. It's a life policy, that basically states- if that animal dies, you get paid... You set the premium price, I think cattle are at 6 or 6.5%, and sheep are 12 or 13%. We've used it several times: lost ewes to prolapse, rams to fighting, and a cow to carrying twins and had complications.
In all cases, you have to get a vet statement to conclude death and state thier reasons. Then the animal goes to the Federal lab, where an autopsy is completed... Of course, this is all paid for by the insurance company.
We also have a blanket farm policy stating that if more than 5 animals get killed by something natural, or crazy.. then we can collect.. but this isn't really what you're wanting to know about.