What replevin action can be taken across state line to get my pet back?

A Penbrook Corgi bitch owner (purchased and AKC registered by owner) allowed the breeder/handler to prepare and show owners dog to obtain Champion status in preparation for breeding. Breeder was to return dog when competition was completed. This was to take a couple of months. The owner arranged transportation of dog from one state to another and paying for food no other costs were agreed upon. Without the owners permission the breeder claims eye and hip checks were performed. She claims the said the dog had poor hips. The Breeder again without the owner permission decided to have the said dog spayed. The breeder is asking for monetary compensation for all she although without permission from the owner. The owner contacted the Vet office but they refuse to reply when asked if they performed the hip X-rays or the Spay. The X-rays never went for OFA certification. The owner refuses to pay and has asked for the return of her dog and the cost of the dog since it was not show quality as advertised to owner originally. Breeder refuses to return dog or payback the original cost of dog. What legal means does the owner have in the case and should she contact the local police first? What steps are needed here? Thank you.