There will likely be a reconditioning of the biologic and genetic makeup of humans and animals. There are broken genes in humans and animals that could contribute to nutrition if they were functional.
Isn't that evolution?? If Jehovah had wanted them to be herbivores, why didn't he make them that way to begin with? Did they start out that way and then de-evolve into carnivores and once the new system is here change back? How far done the food chain will this extend? To bacteria? To flys? Where is the line and why is it there? Without decomposition, the earth will quickly turn into a smelly mess. Unless the animals will also live forever?
Why did the animals start turning on each other after the Fall? What did they do wrong? They didn't sin.
I could never reconcile this teaching with the teaching that animals are not able to sin because they can't reason. Original sin was willful which was something the animals couldn't do.