My moms dog has not wanted to eat for the last 3 or 4 days. She has eaten very little, she lays around a lot. She is an outside mix breed, a large dog.

What can she do?

Take the dog to the vet. That is what she can do. It isn't normal for a dog to be off food for that long a time. Is the dog tied up all the time outside and how old it the dog ?