When is the
Best Time to Spay or Neuter My German Shepherd?......
As a Veterinarian and as a Breeder.......
I generally make it a rule to tell
everyone NOT to spay or neuter their German Shepherd until they
reach at least a year of age. We know that the hormones that
regulate sexual activity (such as testosterone and estrogen) also
interact with the growth hormones and promote the closure of the
growth plates ON TIME. We know that males or females
that are spayed or neutered at an early age will grow SIGNIFICANTLY
taller than those that are spayed later in life. Dogs that
have been spayed or neutered early are typically longer limbed,
lighter boned, have narrower chests and smaller skulls.
Most veterinarians are in a habit of
recommending you get your dog spayed or neutered at 6 months.
Though this is a standard protocol, it is not one that I recommend
for your rapidly growing, large breed, sporting dogs. Abnormal
growth that results from having some growth plates close on time
(due to the presence of sex hormones) and having some growth plate
closures delayed (due to the removal of the testicules or ovaries)
can in turn, dramatically increase your risk of orthopedic issues.
The growth plates of the long bones will close generally between the
ages of 5 and 14 months. If you have your dog neutered
at 6 or 7 months, some of the growth plates will close on time while
others that close later will be delayed. This can result in an
increase level of stress on not only the joints (resulting in
arthritis) but can also affect the tendons and ligaments. In
turn, you may increase your risked of damage to the knees and
elbows, predisposing your dog to torn ACL (anterior cruciate
ligaments) and the like.
The arguments that you will hear in
favor of early spay or neuter include:
- Decrease risk of prostate
problems and testicular tumors
- Decrease risk of mammary tumors
- Decrease risk of pregnancy
- Decrease risk of pyometra
I do believe all of these things are
true but I feel that you still get these same benefits even if you
hold off on your spay or neuter until 1 year of age. I will
address each of these arguments briefly here:
- Prostate -- Prostate problems are
generally not much of an issue until your dog gets to be a
little older. This is also true of testicular tumors
- Pyometras (infection of the
uterus that can result in death) -- Though you can see metritis
in a younger dog, true pyometras generally don't occur until the
dog reaches 5 years of age or older. Spaying before 5
years of age will eliminate that concern.
- Pregnancy -- Most German
Shepherds will not go through a heat cycle until they reach AT
LEAST 8 months of age. Many of my shepherds don't come
into heat until after 1 year of age. It is very important
that you don't let your shepherd get fat. The earlier
maturing, more rapidly growing shepherds are more likely to
cycle earlier. By ensuring that your dog does not get
overweight, you will also ensure that they will come into their
first heat cycle later in life instead of earlier. If you
are planning on spaying and your dog starts to come in heat at
10 or 11 months, I feel that it is less critical if you decide
to spay at this age. Most all of the major growing as
already been done at this point.
- Mammary tumors -- This is where I
think the most valid argument can be found. It is
definitely true that if you spay your female before she has a
chance to go through her first heat cycle, you reduce your risk
of mammary tumors by 90 something percent. Of this fact, I
have no doubt. There is also an increased risk of mammary
cancer after every ensuing heat cycle. However, though the
tumor risk is present, I feel that it is much less than the risk
of orthopedic issues. So, between the two, I would rather
risk mammary tumors (which is approximately 1 in 10 dogs and can
be removed fairly successfully if caught soon enough) than risk
hip dysplasia (which occurs in 80 percent of all German
So, in summary, I strongly recommend
that you wait until your dog is approaching 1 year of age before
considering either spaying or neutering. If you have a female
though and do not want to deal with a heat cycle, keep your dog lean
(not necessarily skinny), and wait as long as possible before
spaying. If you can tell that she is coming into heat, you can
schedule a spay at that time in order to prevent her from bleeding
in your house and attracting all of the neighborhood Romeos.
As a warning though, some veterinarians do not like to spay a dog
that is in heat due to an increase risk of bleeding. Check
with your local veterinarian to see what their policies are.
Early Spay / Neuter Considerations for the Canine Athlete
Early Spay-Neuter Considerations
for the Canine Athlete
One Veterinarian's Opinion
© 2005 Chris Zink DVM, PhD, DACVP
Those of us with responsibility for the health of canine athletes need to continually read and evaluate new scientific studies to ensure that we are taking the most appropriate care of our performance dogs. This article provides evidence through a number of recent studies to suggest that veterinarians and owners working with canine athletes should revisit the standard protocol in which all dogs that are not intended for breeding are spayed and neutered at or before 6 months of age.
A study by Salmeri et al in 1991 found that bitches spayed at 7 weeks grew significantly taller than those spayed at 7 months, who were taller than those not spayed (or presumably spayed after the growth plates had closed).(1) A study of 1444 Golden Retrievers performed in 1998 and 1999 also found bitches and dogs spayed and neutered at less than a year of age were significantly taller than those spayed or neutered at more than a year of age.(2) The sex hormones, by communicating with a number of other growth-related hormones, promote the closure of the growth plates at puberty (3), so the bones of dogs or bitches neutered or spayed before puberty continue to grow. Dogs that have been spayed or neutered well before puberty can frequently be identified by their longer limbs, lighter bone structure, narrow chests and narrow skulls. This abnormal growth frequently results in significant alterations in body proportions and particularly the lengths (and therefore weights) of certain bones relative to others. For example, if the femur has achieved its genetically determined normal length at 8 months when a dog gets spayed or neutered, but the tibia, which normally stops growing at 12 to 14 months of age continues to grow, then an abnormal angle may develop at the stifle. In addition, with the extra growth, the lower leg below the stifle likely becomes heavier (because it is longer), and may cause increased stresses on the cranial cruciate ligament. In addition, sex hormones are critical for achieving peak bone density.(4) These structural and physiological alterations may be the reason why at least one recent study showed that spayed and neutered dogs had a higher incidence of CCL rupture.(5) Another recent study showed that dogs spayed or neutered before 5 1/2 months had a significantly higher incidence of hip dysplasia than those spayed or neutered after 5 1/2 months of age, although it should be noted that in this study there were no standard criteria for the diagnosis of hip dysplasia.(6) Nonetheless, breeders of purebred dogs should be cognizant of these studies and should consider whether or not pups they bred were spayed or neutered when considering breeding decisions.
A retrospective study of cardiac tumors in dogs showed that there was a 5 times greater risk of hemangiosarcoma, one of the three most common cancers in dogs, in spayed bitches than intact bitches and a 2.4 times greater risk of hemangiosarcoma in neutered dogs as compared to intact males.(7) A study of 3218 dogs demonstrated that dogs that were neutered before a year of age had a significantly increased chance of developing bone cancer.(8) A separate study showed that neutered dogs had a two-fold higher risk of developing bone cancer.(9) Despite the common belief that neutering dogs helps prevent prostate cancer, at least one study suggests that neutering provides no benefit.(10) There certainly is evidence of a slightly increased risk of mammary cancer in female dogs after one heat cycle, and for increased risk with each subsequent heat. While about 30 % of mammary cancers are malignant, as in humans, when caught and surgically removed early the prognosis is very good.(12) Luckily, canine athletes are handled frequently and generally receive prompt veterinary care.
The study that identified a higher incidence of cranial cruciate ligament rupture in spayed or neutered dogs also identified an increased incidence of sexual behaviors in males and females that were neutered early.(5) Further, the study that identified a higher incidence of hip dysplasia in dogs neutered or spayed before 5 1/2 months also showed that early age gonadectomy was associated with an increased incidence of noise phobias and undesirable sexual behaviors.(6) A recent report of the American Kennel Club Canine Health Foundation reported significantly more behavioral problems in spayed and neutered bitches and dogs. The most commonly observed behavioral problem in spayed females was fearful behavior and the most common problem in males was aggression.(12)
Other Health Considerations
A number of studies have shown that there is an increase in the incidence of female urinary incontinence in dogs spayed early (13), although this finding has not been universal. Certainly there is evidence that ovarian hormones are critical for maintenance of genital tissue structure and contractility.(14, 15) Neutering also has been associated with an increased likelihood of urethral sphincter incontinence in males.(16) This problem is an inconvenience, and not usually life-threatening, but nonetheless one that requires the dog to be medicated for life. A health survey of several thousand Golden Retrievers showed that spayed or neutered dogs were more likely to develop hypothyroidism.(2) This study is consistent with the results of another study in which neutering and spaying was determined to be the most significant gender-associated risk factor for development of hypothyroidism.(17) Infectious diseases were more common in dogs that were spayed or neutered at 24 weeks or less as opposed to those undergoing gonadectomy at more than 24 weeks.(18) Finally, the AKC-CHF report demonstrated a higher incidence of adverse reactions to vaccines in neutered dogs as compared to intact.(12)
I have gathered these studies to show that our practice of routinely spaying or neutering every dog at or before the age of 6 months is not a black-and-white issue. Clearly more studies need to be done to evaluate the effects of prepubertal spaying and neutering, particularly in canine athletes.
Currently, I have significant concerns with spaying or neutering canine athletes before puberty. But of course, there is the pet overpopulation problem. How can we prevent the production of unwanted dogs while still leaving the gonads to produce the hormones that are so important to canine growth and development? One answer would be to perform vasectomies in males and tubal ligation in females, to be followed after maturity by ovariohysterectomy in females to prevent mammary cancer and pyometra. One possible disadvantage is that vasectomy does not prevent some unwanted behaviors associated with males such as marking and humping. On the other hand, females and neutered males frequently participate in these behaviors too. Really, training is the best solution for these issues. Another possible disadvantage is finding a veterinarian who is experienced in performing these procedures. Nonetheless, some do, and if the procedures were in greater demand, more veterinarians would learn them.
I believe it is important that we assess each situation individually. For canine athletes, I currently recommend that dogs and bitches be spayed or neutered after 14 months of age.
This article is available for download in Adobe Acrobat PDF format
Early Spay Considerations (pdf).
- Salmeri KR, Bloomberg MS, Scruggs SL, Shille V.. Gonadectomy in immature dogs: effects on skeletal, physical, and behavioral development. JAVMA 1991;198:1193-1203
- Grumbach MM. Estrogen, bone, growth and sex: a sea change in conventional wisdom. J Pediatr Endocrinol Metab. 2000;13 Suppl 6:1439-55.
- Gilsanz V, Roe TF, Gibbens DT, Schulz EE, Carlson ME, Gonzalez O, Boechat MI. Effect of sex steroids on peak bone density of growing rabbits. Am J Physiol. 1988 Oct;255(4 Pt 1):E416-21.
- Slauterbeck JR, Pankratz K, Xu KT, Bozeman SC, Hardy DM. Canine ovariohysterectomy and orchiectomy increases the prevalence of ACL injury. Clin Orthop Relat Res. 2004 Dec;(429):301-5.
- Spain CV, Scarlett JM, Houpt KA. Long-term risks and benefits of early-age gonadectomy in dogs. JAVMA 2004;224:380-387.
- Ware WA, Hopper DL. Cardiac tumors in dogs: 1982-1995. J Vet Intern Med 1999 Mar-Apr;13(2):95-103
- Cooley DM, Beranek BC, Schlittler DL, Glickman NW, Glickman LT, Waters D, Cancer Epidemiol Biomarkers Prev. 2002 Nov;11(11):1434-40
- Ru G, Terracini B, Glickman LT. Host related risk factors for canine osteosarcoma. Vet J. 1998 Jul;156(1):31-9.
- Obradovich J, Walshaw R, Goullaud E. The influence of castration on the development of prostatic carcinoma in the dog. 43 cases (1978-1985). J Vet Intern Med 1987 Oct-Dec;1(4):183-7
- Meuten DJ. Tumors in Domestic Animals. 4th Edn. Iowa State Press, Blackwell Publishing Company, Ames, Iowa, p. 575
- Stocklin-Gautschi NM, Hassig M, Reichler IM, Hubler M, Arnold S. The relationship of urinary incontinence to early spaying in bitches. J. Reprod. Fertil. Suppl. 57:233-6, 2001
- Pessina MA, Hoyt RF Jr, Goldstein I, Traish AM. Differential effects of estradiol, progesterone, and testosterone on vaginal structural integrity. Endocrinology. 2006 Jan;147(1):61-9.
- Kim NN, Min K, Pessina MA, Munarriz R, Goldstein I, Traish AM. Effects of ovariectomy and steroid hormones on vaginal smooth muscle contractility. Int J Impot Res. 2004 Feb;16(1):43-50.
- Aaron A, Eggleton K, Power C, Holt PE. Urethral sphincter mechanism incompetence in male dogs: a retrospective analysis of 54 cases. Vet Rec. 139:542-6, 1996
- Panciera DL. Hypothyroidism in dogs: 66 cases (1987-1992). J. Am. Vet. Med. Assoc., 204:761-7 1994
- Howe LM, Slater MR, Boothe HW, Hobson HP, Holcom JL, Spann AC. Long-term outcome of gonadectomy performed at an early age or traditional age in dogs. J Am Vet Med Assoc. 2001 Jan 15;218(2):217-21.