It is possible for dogs to ingest the rabbit feces and coccidia organisms within them and for those organisms to show up in a fecal examination done on the dog's stools. (vetinfo.com)
A puppy is not born with the coccidia organisms in his intestine. (michiganpuppymills.com)
According to «Applied Pharmacology for Veterinary Technicians,» sulfa drugs do not kill the coccidia organisms but instead inhibit their regeneration and allow the dog's own immune system to rid the body of the microorganisms in a span of one to three weeks. (cuteness.com)