Patricia - my instructions upon leaving Michigan State University after adrenal surgery: "If at any time you feel that he is unable to void urine and seems obstructed, please call immediately. We do not expect this to happen." Also I don't know if Sparky had trouble urinating before the surgery or not. It also reported that my Calvin was able to pass a fair amount of urine before leaving but because he had been straining prior to surgery that he would continue to strain for the next few weeks. He actually continued to strain for about the next 3 months. If Sparky doesn't pass any urine I would definately contact the vet ASAP. Eunice Keely Calvin and Gypsy [Posted in FML issue 2654]