If a dog eats a dead animal the dog is likely to be just fine.
Although if the dog ate a dead animal that had a disease or was poisoned then the dog may become ill or die themselves.
But if a dog just happens to eat any dead animal such as a dead bird then the dog will almost 100 percent be just fine.
Although it's not recommended for the dog to eat dead animals it's unlikely to harm the dog.
Dogs eat dead animals a lot and survive just fine.
If the dead animal had any bad bacteria or disease in it then it may cause issues or kill the dog but that's rare.
A dog could die from eating a dead animal if the dead animal had any poison in their body or the dead animal died of some bad disease.
However if the dead animal had just died then it's unlikely the dog would would or be harmed from eating the dead animal.
Dogs, wolves etc all ate and eat dead animals all the time in the wild for survival so it's not always a bad thing if you dog did eat a dead animal.
However it's best to keep your dog away from any dead animals and do your best to prevent the dog from eating the dead animal.
If your dog did eat the dead animal though then just keep an eye on them for any health issues such as vomiting, diarrhea, weakness etc.
If you're worried you can take your dog to the vet.
But in most cases the dog who ate the dead animal will be just fine.