Cannibalism seriously threatens a species' survival. Risk of disease from eating same-species meat is a good way to stop it.
http://www.petplace.com/article/small-mammals/general/when-y...
Rabbits are somewhat infamous for eating their young.
I'm not sure there is any research about it, but it could be a resource preserving behavior.
Nevertheless, cannibalism can be a real risk for some species and adaptations to prevent it are useful, especially in the case of mammals.
Specie A (with this disease) stop cannibalizing after seeing the outcome, better chance of survival.
Specie B (without this disease) eat themselves to the last person... Lower chance of survival as a specie.
Nature "cares" by generating lots of options, then let the fittest to survive. So while nature doesn't intend or plan for a specie to survive, the outcome is no different from if it did. I believe the OP means "care" in this sense.
That seems unlikely. A bigger risk would be a carnivorous species exterminating its prey species.
Rather, they mean "Could this be the way that the species' internal biological and evolutionary processes are involved in preventing cannibalism?" Personally, I think "nature's way" is a highly preferable and convenient shorthand. :)