The components of the urinary system are the bladder, prostate, and urethra, as well as the kidneys and uterus. The system works together. The two kidneys siphon excess waste created by ordinary metabolism, yet regulate water and minerals. Wastes are deposited into the ureter, which empties into the bladder. Urine passes from the bladder to outside the body via the urethra (in the male, the urethra also transports semen).

If all is functioning well, your puppy will urinate regularly (not frequently), and his urine will be clear and yellow in color. A problem of the kidneys, bladder, urethra, or prostate will be evident as straining to urinate, blood-tinged or cloudy urine, excessive drinking accompanied by excessive urination, or pain upon urination. The problem could be something as minor as dehydration or as complicated as renal failure. You must consult your veterinarian for a diagnosis.

The reproductive system of the female (bitch) includes two ovaries, a uterus, and fallopian tubes. A spayed female will have all of these removed. Intact females will experience regular heats and are prone to false pregnancies and infection of the uterus called pyometra.

You and your female dog will be happier and healthier if she is spayed. Some believe that a spayed bitch is prone to obesity. While it is true that she will not be under the same hormonal influence that keeps an intact bitch in form, with regular exercise and the proper diet, a spayed bitch can be kept in top shape.

The male dog's reproductive system includes the testicles, penis, and prostate gland. Intact males are prone to damage or injury of the penis or scrotum, cancer of the testes, and inflammation, enlargement, or cancer of the prostate. Once again, you and your dog will live happier, healthier lives if the dog is neutered. Neutering is the surgical removal of the testicles. The empty scrotum eventually shrinks and leaves no scar.

Neutering not only guarantees the male won't develop testicular cancer or prostate problems, it also lessens a male's territoriality, making him (with proper care and training) a friendlier pet. Neutering does not significantly change a dog's temperament, however; if you have an aggressive male or one with housebreaking issues, neutering will not solve the problem, but combined with training, it can certainly help.