POPULATION CONTROL: Professional kennels may use contracts, withhold registration papers, or use limited registrations to induce new owners to alter pet quality animals.

BEHAVIOR MODIFICATION: Neutering a dog not only eliminates accidental breeding, it reduces and in some instances eliminates sexually-related problem behaviors. Female dogs can show signs of puberty as early as five months of age. It is during estrous, or "heat" that female dogs accept a mate and can become pregnant. Carpet and furniture may be stained by vaginal discharge of blood that occurs during heat. Male dogs arrive from miles away to pay her court. They hang around night and day for the duration of her cycle, which typically occurs twice a year and lasts about twenty-one days, but is often variable. Spaying prevents unplanned litters, unsightly stains, and ends the aggravation of courting canines staked out in your front yard. Male dogs are able to breed from five to nine months old on, depending on the breed. Intact males aggressively mark their territory -- the kitchen wall, your bed -- with urine. They may engage in embarrassing "mounting" behavior. They often roam far from home seeking receptive females, and engage in ferocious fights for dominance with other males. Neutering dramatically reduces and in some instances eliminates objectionable behavior. An April 1991 JAVMA article by Benjamin L. Hart, DVM, PhD, says about fifty to sixty percent of male dogs that are neutered stop urine marking in the house, fighting with other male dogs, or inappropriate mounting behavior. In that same JAVMA issue, Shirley D. Johnston, DVM, PhD says roaming behavior decreased in more than ninety percent of dogs after castration.

HEALTH BENEFITS: Reducing or eliminating aggressive behavior means castrated dogs have fewer fight wounds. When Poochie stays closer to home, risk of injury from encounters with cars and other animals is also reduced. Castration also decreases incidence of some illnesses. Dr. Johnson says testicular cancer accounts for four to seven percent of all canine tumors, while prostatic disease occurs in more than sixty percent of sexually intact male dogs over five years old. Castration reduces and in some cases eliminates the chance of a dog ever suffering these problems. Dr. James Richards, DVM of Cornell University says spaying eliminates problems with serious uterus infections like pyometra (a pus-filled uterus), metritis (inflammation of the uterus) and endometritis (inflammation of the lining of the uterus). Dr. Johnston adds, "Sexually intact females have seven times greater risk of mammary cancer than neutered females." Up to fifty percent of mammary gland tumors in dogs are malignant. Bitches spayed before their first heat have only .5 percent risk for this tumor; if spayed after one heat, the risk is eight percent; for intact bitches and those spayed after their second season, the risk climbs to twenty-six percent.

DISPELLING MYTHS: Myths serve as excuses to avoid neutering a dog. There is absolutely no evidence that breeding a dog is "good for it." In fact, intact dogs are at much higher risk for health problems than neutered animals. Most of us agree that random bred dogs should be neutered, yet we often balk at fixing purebreds. But just because a dog is "registered" does not mean it's a show quality animal; most are not. The very existence of purebred rescue clubs testifies to the many wonderful purebreds left homeless every day -- and even one is too many. Often, owners want to breed an aging pet to "get a puppy just like Duke." Others want to breed to "get back" the cost of buying the dog. "There is absolutely no way you can properly raise a litter and make any money at all," says Hunt. She calls genetics an inexact science where an inept match results in puppies with bad dispositions and worse health problems. Even when you know what you're doing, the chance of reproducing Duke is next to zero. And what will be done with Duke's littermates? Bunting says parents often want children to experience the "miracle of birth," but mom-dog rarely schedules a whelping for human convenience -- chances are, she'll hide. Breeding for this purpose only demonstrates pets can be created and discarded as it suits us. The real miracle is life; teach children that preventing the births of some pets saves the lives of others. Neutered dogs do not automatically get fat and lazy. According to Dr. Hart, behavioral patterns such as watch-dog barking, hunting, playfulness, activity level, and seeking affection, are not altered by neutering. And Dr. Johnston says there's no data in the veterinary literature to support or disprove that free-feeding intake and exercise change after castration. Studies have shown that only about thirty to forty percent of spayed dogs gain weight due to hormonal shift. "Spayed and neutered pets require fewer calories," says Dr. Ken Lawrence of the Texoma Veterinary Clinic in Sherman, Texas. "They just need to eat less." Dogs shown in conformation trials must be intact. "But I finished a bunch of dogs I never bred," says Heckerman. "Even though they can be finished doesn't necessarily mean they should be bred." Only dogs that are extraordinary examples of a breed, and that will be used in a professional, reputable program should be bred. For others, experts agree that neutering makes your dog a better pet.

TIMING IS EVERYTHING: To reap the most health benefits, avoid behavior problems, and prevent unplanned puppies, dogs should ideally be neutered before reaching sexual maturity. "Traditionally, the veterinary community said six months of age is the best time," says Dr. Richards. But depending on the breed, a dog could go into season as early four months and have puppies. This is one reason many experts now advocate neutering dogs at much younger ages. Consult your veterinarian for the best time to neuter your dog. Healthy male dogs may be castrated at any time, but veterinarians recommend spaying females when they are not in heat. When the estrogen levels are high, as they are during heat, the uterus and vessels engorge with blood and there's an increased risk of bleeding. What if Princess pulled off a "Great Escape" last week, picked the window lock with her rabies tag, shimmied down the fire escape and disappeared for an hour -- what if she's already pregnant? Dr. Lawrence says spaying dogs in very early stages of pregnancy is not a significant problem. "But beyond two weeks, you need a larger incision," he cautions. Pregnancy prolongs the surgery and increases the risk and the cost. "If the dog is nursing," says Dr. Lawrence, "we prefer to wait until the milk goes down." During nursing, the mammary veins become engorged; more care must be taken to avoid them during surgery, and the incision may have a bit more oozing afterwards. Cost of neutering varies from practice to practice. In my area (North Texas), routine dog spays cost between $68-98.50 depending on the size of the dog, and dog castration runs $56-76.50. Compared to the cost of raising puppies, Hunt says neutering is very economical. Dr. Richards believes veterinarians try to keep the cost low to encourage people to have the procedure done. "Because it's such a common procedure," says Dr. Richards, "veterinarians get very good at them. We call them routine, but no surgical procedure can be taken lightly."

PRELIMINARIES: Most veterinarians ask clients to withhold food and water for a period of time prior to surgery, to make sure the dog's stomach is empty. If the dog vomits while under anesthetic, vomitus can be aspirated -- go down into the airways -- which can be potentially lethal. If your dog somehow manages to eat or drink beyond the recommended cut-off point before surgery,

TELL THE VETERINARIAN! "If we know," says Dr. Richards, "we can delay the procedure a little bit." Neutering is an anesthetic procedure -- that is, the dog is completely asleep during the surgery. Both injectable and inhalant anesthetics are used, alone or in combination, and many practices offer preanesthetic blood work that helps determine which anesthetic is best for the animal. Most dogs are sedated so they can be prepared for surgery. Dr. Lawrence says most dogs are given atropine, which keeps their heart rate from slowing down, and dries up their respiratory secretions. "Then they're given something like pentothal, which is a barbiturate anesthetic, to induce them," he says. Once asleep, the dog will have an endotracheal tube placed. One end of the tube goes into the dog's mouth and down its throat, while the other end attaches to the anesthesia machine. A gas anesthetic, like halothane or isofluorane, is administered directly into the dog's lungs. The advantage of inhalant anesthesia is the dosage can be adjusted during surgery, and the dog awakens quickly after the anesthesia is stopped. The surgery is a sterile procedure, which means the surgery site must be disinfected or "prepped" for surgery. First, the fur is removed. In spay surgeries, the dog's tummy is shaved; for castrations, the hair surrounding the scrotal sack is shaved. "Then the sites are scrubbed with antiseptic soaps, just like any surgical procedure in humans," says Dr. Richards. Common surgical prep solutions include betadyne and alcohol, or chlorhexidine and alcohol. The scrubbing procedure is repeated three times to ensure sterility. The dog is positioned tummy up on the surgery table on a towel or heating pad to keep it warm during the surgery. Monitoring procedures during the surgery vary from practice to practice. "With gas anesthesia," says Dr. Lawrence, "we use both respiratory and cardiac monitors." Some veterinarians even use an EKG machine. "Finally, pets are draped with sterile towels," says Dr. Richards. "Sterile gloves are used, sterile gowns, sterile instruments, the whole deal. Neutering is quite an involved procedure."

CASTRATION SURGERY: The surgery to neuter male dogs is usually less involved than neutering females. Testicles are inside a skin sac called the scrotum, and are attached to spermatic cords containing an artery and the vas deferens (spermatic duct). While the dog is positioned on its back, a small slit in the sterile drape is aligned and secured over the shaved and scrubbed area in front of the dog's scrotum. Surgery is performed through this opening in the drape to keep the surgical field sterile. "Most people do a single incision anterior to (in front of) the scrotum," says Dr. Lawrence. Then the testicle is pushed out of the scrotum through that single one to two inch incision. The spermatic cord is ligated, or tied, to prevent bleeding, then the testicle is cut free. The "stump" of the spermatic cord recedes back into the incision. The procedure is repeated on the second testicle, leaving the scrotal sac empty. Dr. Lawrence says male dogs have a tendency to lick at skin sutures. "Instead, we do a subcuticular stitch that's absorbable," he says, "we suture the underside of the skin." A routine castration procedure takes ten to twenty-five minutes of actual surgical time. In rare cases, there's a failure of one or both testicles to descend into the scrotal sac as the dog matures. This inherited condition (a testicle is retained in the abdomen) is called cryptorchid. Dr. Lawrence says dogs with this condition have a thirteen times greater incidence of tumors in that retained testicle. Because both testicles must be removed to prevent unwanted sexual behaviors, a veterinarian must go into the abdomen to castrate a cryptorchid dog.

SPAY SURGERY: Spaying is much more involved than castration. "People must realize spayed dogs have undergone a major abdominal surgery," says Dr. Richards. The dog is positioned on its back with the small slit in the sterile drape aligned and secured over the dog's shaved and scrubbed abdomen. The surgeon makes an incision in the skin of the dog's tummy, usually just below the belly button and along the midline. The average incision is an inch to two inches long. The surgeon's knife, called a scalpel, cuts through the surface skin, then through the subcutaneous fat, and finally through the abdominal wall. Once the abdomen is opened, special instruments hold the incision apart so the surgeon can better see. A long metal instrument with a smooth hook on one end (spay hook) is inserted into the abdomen to retrieve the uterus. The uterus is shaped like a "Y" with an ovary attached to the top of each "horn"; an ovarian artery, vein and nerve are attached to each ovary. Using a gloved forefinger, the surgeon follows a "horn" of the uterus forward to find each ovary in turn. The ovarian ligament that attaches each ovary to the wall of the abdomen is detached, to allow ovaries and uterine horns to be brought further out. Each ovary is tied off two to three times with absorbable suture material to prevent bleeding. "Some veterinarians use little stainless steel clips called "hemoclips" that do the same thing," says Dr. Lawrence. After they're tied off, each ovary is cut free just beyond the sutures. After ensuring there is no bleeding, the ligated stumps containing the ovarian artery, vein and nerve are released and allowed to go back into the abdomen. Next, the surgeon double ties the uterus just beyond the cervix, then severs the uterine stump just beyond the tie. Again, care is taken to verify there is no bleeding, and then the uterine stump is allowed to go back into the abdomen. The excised uterus and ovaries are discarded. The surgeon takes one last careful look inside the dog's open abdomen to be sure there is no unexpected bleeding. Only then is the abdomen sewn shut. Usually, internal stitches are done with absorbable sutures that the dog's body will dissolve over time. However, surgeons have their own preferred methods, which may include staples or even metal suture material. A curved needle is used to place the stitches, and the opening is sewn in three layers. First the abdominal wall, then the subcutaneous tissue (including fat), and finally the surface skin are stitched closed. Tiny, meticulous individual stitches are used, each separately knotted and cut. A routine spay procedure takes twenty to forty-five minutes of actual surgical time.