The vet said it was a "pile infection" basically a uterus infection that shows up sometimes after the dog has been in heat. The vet also said it happens to 1 in 10 dogs and is normally treatable with anti-biodics and then spaying. My wife and I still think it was something else, some poison or something but have no proof. Sure sucks losing 2 dogs in 5 days, one being only 6yrs old!