My sister has had a full blood, papered, bull mastiff pup for over 8 months now, his name is Loki. He went to the Vet today after not eating for a day and half, just drinking liquids. The Vet gave him an IV, but wasn't optomistic. He called her two hours later and said that he had passed. He didn't think that anyone had poisoned him and that it didn't look like any disease(he has had all of his vaccinations). Vet was dumbfounded and asked her if he may perform a necropsy(not sure on spelling). The results found that while a corn cob was lodged in his intestines. She remembers that two days ago, she had put him in the yard to play while she cleaned the home, and heard neighbor children by the back fence. She didn't think anything of it at the time, these children loved Loki and often petted him through the fence. Rest in peace, Loki. You will be greatly missed. Not sure why the Vet didn't do an xray to check stomach and intestines...but, I know that even Vets miss things.