I get asked all the time what age is best to neuter or spay your German Shepherd Dog. I try and stay informed on current research specific to the breed. Below are my thoughts.

I heard that neutered and spayed dogs get fat and lazy. Is this true?
Spaying and neutering does change the metabolism of companion animals, so in most cases, they do not need as much food to maintain their weight as unspayed/unneutered dogs. The problem is not with the dog – it is us. We just tend to overfeed our dogs, and neutered/spayed dogs are more apt to put on weight because of that.
As for laziness, again, the amount of exercise our dogs receive and their activity levels are often dependent on us. If we do not give them opportunities for play and exercise, they can become couch potatoes just like some people. Many spayed/neutered dogs hunt, heard, are entered in agility or obedience shows, become service dogs, and are trained in search and rescue. These dogs are anything but lazy.

When should I have my puppy Spayed or Neutered?
Many veterinarians have started early spaying/neutering as young as 6 weeks of age. Current research is all over the place as the appropriate age or if you should have it done at all. I’ve seen both positive and negative data on almost every scenario. In the end I say it is a personal decision left up to you and your vet, therefor I have no contractual requirements in regards to the age you should spay or neuter your dog. I’ve seen and experienced more reasons to have them spayed/neutered than to leave them intact. I recommend that you spay/neuter your dog no less than 6 months of age, but current research suggest after 1 year of age is best.

Do you require spay/neuter contracts on your puppies?
No, although I strongly encourage you to have your puppy spayed/neutered I do not contractually require it. I place all of my puppies as family pets, if you are interested in breeding please contact me for more specific information.

Females / Spaying:
Having a litter of puppies may seem like a fun thing to do. Some even believe that it helps their female dog, in some way, to develop more completely or become a better pet. Neither is true. Becoming pregnant and having a litter of puppies in no way alters the maturity level of the dog, either physically or mentally. In most cases, people find out that it is hard to find good homes for all of the puppies, regardless of the selling price. In addition, not all pregnancies go smoothly. Difficult labor, puppy mortality, and potential health problems in the mother, such as uterine and mammary gland infections, can take all the fun out of the experience.
Having your dog spayed will prevent her from becoming pregnant, it also eliminates the twice-yearly heat cycles. The surgery removes the source of production of such hormones as estrogen and progesterone. These hormones are responsible for stimulating and controlling heat cycles and play a major role during pregnancy. But they also have other effects on the body and some of them are potentially harmful.
Spaying your dog eliminates most, if not all, of the female hormone production. In so doing, the real advantages of this procedure are realized. In human cases, great efforts are undertaken to maintain or restore hormone production in the body, but the same is only rarely true in canine practice. These hormones play key roles in reproduction in the dog. However, they can also have many unwanted side effects.

Estrus: During the heat cycle there are behavior and hygienic problems that develop. Females in heat will actively search out male dogs and may attempt to escape from the house or yard, putting them in the danger of traffic, fights with other animals, etc. Often there is a sudden influx of male dogs around the home and yard. These dogs leave numerous droppings and spray plants and trees with urine in an attempt to mark their new found territory. Owners also need to contend with the vaginal bleeding that typically lasts for a week, but could last up to three weeks.

Mammary cancer: Estrogen is one of the primary causes of canine mammary cancer, the most common malignant tumor in dogs. Animals that are spayed prior to one year of age very rarely develop this malignancy. Spaying a dog before her first heat is the best way to significantly reduce the chance your dog will develop mammary cancer. The risk of malignant mammary tumors in dogs spayed prior to their first heat is 0.05%. It is 8% for dog spayed after one heat, and 26% in dogs spayed after their second heat.

Tumors of the reproductive tract: Tumors can occur in the uterus and ovaries. Spaying your dog would, of course, eliminate any possibility of these occurring.

Uterine infections: Many female dogs have problems with a severe uterine disease called pyometra following their heat cycles. With this disorder, a normal three-ounce uterus can weigh ten to fifteen pounds and be filled solely with pus. Undetected, this condition is always fatal. Its treatment requires either the use of expensive hormonal and IV fluid therapy or an extremely difficult and expensive ovariohysterectomy. A normal spay costs between $100 and $400, while one done to correct a pyometra can easily cost $600 to over $1000, depending on complications. The strain on the kidneys or heart in some of these cases may be fatal or cause life long problems, even after the infected uterus has been removed.

False pregnancy: Some bitches fail to routinely go out of their heat cycles correctly causing a condition we call ‘false pregnancy.’ In these cases, even though she may not have mated with a male dog, her body believes it is pregnant due to some incorrect hormonal stimulations that it is receiving. The dog may just have some abdominal swelling and/or engorgement of the mammary glands, but in some cases, they will even make nests and snuggle with socks or toys against their bodies. These animals often experience no long term serious problems, as the behavior disappears when the circulating hormones return to their appropriate levels. In others, we may see mastitis (infection of the mammary glands), metritis (infection of the uterus), or sometimes these cases develop into full-blown pyometras. I recommend spaying dogs that consistently have false pregnancies.

Hair coat problems: In dogs, hair does not grow continuously as in people, but has a definite growing (anagen) and resting (telogen) phase. Estrogen, which is increased during estrus, retards or inhibits the anagen phase, so more hairs are in the telogen phase. These resting hairs are more easily lost because they are less firmly anchored. As a result, the hair coat on many dogs suffers because of estrogen surges that occur with heat cycles or whelping. Their coats appear thin and the underlying skin is exposed in many areas. It can take two to four months for the hair to return to normal. Additionally, there are a small number of female dogs that never develop a normal hair coat because of the cycling hormones. Their coats are consistently thin over the sides of their bodies and these cases are sometimes confused diagnostically with hypothyroid animals. The only treatment for these dogs is to have them spayed.

Should let my dog go through one heat before I have her spayed?
Spaying a dog before her first heat is the best way to significantly reduce the chance your dog will develop breast cancer, a common condition in female dogs. The risk of malignant mammary tumors in dogs spayed prior to their first heat is 0.05%. It is 8% for dog spayed after one heat, and 26% in dogs spayed after their second heat.

Any heat brings with it a chance your dog could become pregnant. This would adversely affect the health of a young dog.

A heat also brings with it the chance for accidents. Dogs in heat have been known to run through glass patio doors, jump out of moving cars, and be hit by cars as they attempt to find a mate.

Owners of females in heat also frequently have to deal with a sudden influx of male dogs around the home and yard. These amorous visitors leave numerous droppings, and spray plants and trees with urine in an attempt to mark their new found territory. There is also the mess and hassle of vaginal bleeding that can last as long as three weeks. Who wants to deal with that if they do not have to?

Males / Neutering:
Other than population control, there are lots of very, very good reasons to castrate/neuter (remove the testicles from) male dogs. They basically fall into one of two categories – they are either behavioral or medical. Regardless of which category we are talking about, most of the unwanted characteristics or conditions are caused by the male hormone testosterone, which is produced within the testicle.

Behavioral Advantages of Neutering:

Decreased Aggression: One of the most important behavioral advantages of castration is that as adults, these dogs will tend to be less aggressive both toward other male dogs and also people. The androgen (male) hormones, of which testosterone is the most important, are responsible for the development of many behavioral patterns. When young puppies are sexually mounting their 7 and 8-week old litter mates this is because of androgen surges in their bodies. The same is true with aggressive behavior. The degree castration has on suppressing aggression varies between animals and the age at which it is done. Its effect is greatest if it is done before one year of age.

*Anytime a client has had any aggression issues two things they almost always have in common. They are over 1 year of age and they aren’t neutered!

Decreased Roaming: A second behavioral advantage of neutering is that these dogs will not ‘roam’ when they sense a female in heat. Male dogs can sense females in heat through pheromones. These are airborne chemical attractants that are liberated from the female when she is cycling. They travel through the air for great distances. Pheromones are, to say the least, very effective stimuli. If dogs are neutered at an early age, they will not sense or respond to pheromones, and would certainly be less stressed and tend to stay home.

Increased Concentration: A third behavioral advantage occurs when you are training or working your dog, or using him for field work. If neutered, he will be a much better student with a much longer attention span when there are females nearby that are in heat. This is because he will not be constantly distracted by pheromonal stimuli.

Medical Advantages of Neutering:

The medical advantages are numerous and even more significant. Again, all are caused by the effects of testosterone on the body or are physical problems that arise within the testicles themselves.

Testicular Tumors: There are several different tumor types, both benign and malignant, that arise within the testicles. As with most cancers, these usually are not noted until the animal reaches 5 or more years of age. Therefore, these would not be a problem in those individuals castrated at the recommended age.

Fewer Hernias: A hernia is a protrusion of an organ or parts of an organ or other structure through the wall of a cavity that normally contains it. Perianal hernias occur when the colon, urinary bladder, prostate, or fat protrude from the abdominal cavity, through the muscular wall by the anus and then lie just under the skin. This type of hernia is far more common in older, unneutered male dogs. The levels of testosterone and other hormones appear to relax or weaken the group of muscles near the anus. When the animal then strains to defecate or urinate, the weakened muscles break down and the abdominal organs and fat bulge out under the skin. In short-haired breeds, this large bulge is noted by the owner almost immediately, but in the long-haired dogs, the problem may go on for months before anyone realizes there is an abnormality. Left untreated, these organs may become damaged, unable to function or even die from loss of blood supply. Additionally, because of the displacement of organs into this area, the animal may not be able to defecate or urinate correctly or completely and may become constipated or have urinary incontinence (dribble urine). The surgery to repair this condition is not simple and can easily cost hundreds of dollars.

Fewer Perianal Tumors: There are tumors whose growth is stimulated by testosterone. These occur near the anus and are called perianal adenomas (benign) or perianal adenocarcinomas (malignant). As with the hernias, these usually do not occur until the dog is at least 7-years old. They require surgical treatment and should be caught early in their development to prevent recurrence. These tumors and the above hernia are very, very rare in those individuals castrated before 7 months of age.

Fewer Prostate Problems: The most common medical problems eliminated in dogs neutered at an early age are those involving the prostate. Over 80% of all unneutered male dogs develop prostate disease. Prostate conditions such as benign enlargement, cysts, and infection are all related to the presence of testosterone.

Article that I like about joint disorders as it relates to the age in which the dog is altered:
Some of the Information Provided by: Veterinary Services Department, Drs. Foster & Smith, Inc GR; Withrow, SJ; MacEwen, EG. Tumors of the mammary gland. In Withrow, SJ; MacEwen, EG (eds). Small Animal Clinical Oncology. W.B. Saunders Co. Philadelphia, PA; 2001 455-477.