I believe that the most common creationist belief is that meat-eating started right after the Fall, not after the Flood. There was no death and suffering before the Fall, but eating that darned apple brought death and disease, suffering and a taste for meat.
That said, it is one of the silliest parts of the creationist dogma. I mean, why wouldn't there be carnivorous animals (and plants!) before the fall? The fact that the Bible allows people to eat meat of animals but not to eat other people, and the death of humans is treat as more serious than the death of animals, so it would be perfectly consistent to allow animals to kill and eat other animals before the Fall while humans remain a special creature, protected from the death that other life must suffer. And since, supposedly, animals don't have souls, one wonders whether a creature without a soul (the repository of consciousness in many Christians' beliefs) could even "suffer".
On the other hand consider the lion. It is built to eat meat. Its claws and teeth make it very difficult to obtain plant food in enough quantity to feed itself, and its digestive tract is too short to efficiently digest plant matter. The panda is a case in point -- it is descended from carnivores and has the carnivore digestive system, but since it mainly eats plants now it must eat constantly. It also has certain adaptations that allow it obtain its food more efficiently.
So either the loving god who doesn't want his creation to suffer made lions that would be hungry all the time, or right at the fall every lion suddenly grew teeth and claws and lost a lot of intestine -- the changes would be far more "micro-evolution" than required to produce a human from a chimpanzee-like ape.
But maybe god, knowing that it would only take a couple of hours before Adam and Eve would fall, made lions as carnivores, knowing that they would only be hungry for a couple of hours. But by designing a world prepared to fall, one wonders how one can say that god ever really intended for humanity to life in a peaceful, perfect world.