Anemia can be caused by so many different things.
Here are some links
First I think it is important that we have some idea what are Vet’s are talking about with blood counts.
First one has a nice breakdown on what they look for in a CBC http://www.peteducation.com/article....&articleid=987
When dogs ingest something they shouldn't, inducing vomiting might not be a good idea, and may do more damage than harm. A call to poison control hotline, vet, or the emergency clinic should ALWAYS precede inducing vomiting.