Take out no vengeance on who ever yourself. The final persons that may suffer is your self and family. Talk with a lawyer and see what legal actions you may have. That is the only safe recourse. Probably radiator fluid was put in the water. Dog will drink this till they pop. Understand there is no saving a dog when this stuff gets into it's system.

Sorry for your loss. The Sorrell dogs are becoming a rare commodity, hate to hear you lost that dog. If at all possible try to move out in the boonies away from the suburbs and city. John Q. public has been media brain washed to believe our dogs are very evil. That the only good bulldog is a dead one. Take Care