Early Spay

[D'Elle]

I received an article recently that said that it was potentially dangerous to spay or neuter at a young age. This article suggested waiting until the dog was at least 14 months old, or through puberty. As I am hoping to get a puppy, this is an important consideration for me. I did a search for this topic, but did not come up with anything here. Does anyone know about this? I could copy and paste the article here if anyone wants me to.

Thanks

D'Elle

[D Strickland]

I received an article recently that said that it was potentially dangerous to spay or neuter at a young age. This article suggested waiting until the dog was at least 14 months old, or through puberty. As I am hoping to get a puppy, this is an important consideration for me. I did a search for this topic, but did not come up with anything here. Does anyone know about this? I could copy and paste the article here if anyone wants me to.

Thanks

D'Elle

 

 

I read the same thing a few years ago. The article said that it had something to do with waiting until the growth plates were done filling-in. Something about spaying/neutering changes something in the dog's metabolism and can affect how they finish growing.

[Rave]

I'd like to see the article just to see if I'd read it before.

 

It's the general practice among dog sports competitors now to leave their dogs intact until they're physically mature so that they fully develop in the balanced way nature intended. There have been a few studies done, but really not enough IMO, which is why I'm always curious to read what's out there.

 

From my previous research and discussions with vets, the perceived "dangers" are possibly more risk for cruciate tears and possibly unbalanced overall. The hormones are what signal the growth plates to close, so by removing those before the dog is physically mature their growth plates stay open longer, which may result in uneven and longer growth. The height difference when measured in one study was pretty minimal though. It's really more about balance and proper muscle development so as not to unduly stress the joints or body.

 

That said, there are no REAL dangers to spaying before maturity, as has been the practice for quite a long time now.

[Maralynn]

I prefer to wait until a dog is 18-24 months to spay or neuter. I've read studies that say one thing and studies that say another, but it makes sense to me to wait to cut off those hormones until my dog is physically and mentally mature. Of course my youngster was spayed at 6 months before I got her and it sure wasn't a make or break issue for me in getting her.

[BrittanyS]

Most sport handlers have told me to wait until the growth plates are done growing, and the only way you can tell is through x-rays.

 

I plan on waiting until my pup is around 14 months to neuter.

[D'Elle]

Here is the article:

 

Early Spay-Neuter Considerations for the Canine Athlete

One Veterinarian’s Opinion

© 2005 Chris Zink DVM, PhD, DACVP

www.caninesports.com

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.

Orthopedic Considerations

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 pubjerty (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.

Cancer Considerations

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.

Behavioral Considerations

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.

References:

1. Salmeri KR, Bloomberg MS, Scruggs SL, Shille V.. Gonadectomy in immature dogs: effects on skeletal,

physical, and behavioral development. JAVMA 1991;198:1193-1203

2. http://www.grca.org/healthsurvey.pdf

3. Grumbach MM. Estrogen, bone, growth and sex: a sea change in conventional wisdom. J Pediatr Endocrinol

Metab. 2000;13 Suppl 6:1439-55.

4. 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.

5. 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.

6. Spain CV, Scarlett JM, Houpt KA. Long-term risks and benefits of early-age gonadectomy in dogs. JAVMA

2004;224:380-387.

7. Ware WA, Hopper DL. Cardiac tumors in dogs: 1982-1995. J Vet Intern Med 1999 Mar-Apr;13(2):95-103

8. Cooley DM, Beranek BC, Schlittler DL, Glickman NW, Glickman LT, Waters D, Cancer Epidemiol Biomarkers

Prev. 2002 Nov;11(11):1434-40

9. Ru G, Terracini B, Glickman LT. Host related risk factors for canine osteosarcoma. Vet J. 1998 Jul;156(1):31-

9.

10. 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

11. http://www.akcchf.org/pdfs/whitepapers/Bie..._Conference.pdf

12. Meuten DJ. Tumors in Domestic Animals. 4th Edn. Iowa State Press, Blackwell Publishing Company, Ames,

Iowa, p. 575

13. 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

14. 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.

15. 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.

16. 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

17. Panciera DL. Hypothyroidism in dogs: 66 cases (1987-1992). J. Am. Vet. Med. Assoc., 204:761-7 1994

18. 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

[Gloria Atwater]

So, I'm curious. What about spaying a dog at say, 6 or 8 months? How much of a difference will that make? I spayed my girl, Gael, at 6 months because I didn't want her to come into heat with her intact brother in the house. Now we've a 5 month old Aussie girl who will also be a working dog, and I'm pondering whether we want to suffer through that first heat (while we keep poor Nick on restriction for 2 or 3 weeks) or get her spayed in the next month or so.

 

What is said about spaying when the dog is half-way grown? Anybody? Bueller?

Cheers ~

 

Gloria

[Journey]

There are lots of thread regarding the exact question you have. I personally like the Zink article! Here's one of the threads about early s/n Early Spay. The searches may be tricky but I know there are quite a few threads on the boards that may help you out. In the end it's up to you and how responsible you are at managing an intact dog until they are fully mature.

[airbear]

And just to balance this oft-quoted article, here is a response: Rebuttal to “Early Spay-Neuter Considerations for the Canine Athlete”

 

For example

....Orthopedic Considerations

...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. ...

 

Dr. Howe responds

Dr. Zink points out correctly that in Salmeri’s 15-month study (examining the effects of prepubertal gonadectomy on skeletal growth, weight gain, food intake, body fat, and secondary sex characteristics in 32 mixed-breed dogs neutered at seven weeks or seven months or left intact) that bitches spayed at 7 weeks grew significantly taller than those spayed at 7 months, and that those spayed at 7 months has significantly delayed closure of the growth plates (but didn’t grow significantly taller) than those not spayed (Salmeri, 1991). However, the concerns expressed by Dr. Zinc regarding changes in stifle joint angles are not supported by any existing literature, and don’t make sense as an argument against “early age “gonadectomy (ie, gonadectomy performed well before 6 months of age). Since the animal that is gonadectomized early will not have likely had closure of any of the hind limb long bone physes, it stands to reason that closure of all of the physes will be delayed resulting in longer, but proportional, bone growth as related to the stifle joint. In fact, Salmeri’s study did not identify any changes in the proportional nature of bone growth of the forelimb (she was studying growth and maturation of the radius and ulna). It seems that Dr. Zink may be arguing against performing gonadectomy during the time period between 7 or 8 months of age and final closure of all the growth plates, which isn’t relevant to a discussion of “early age” gonadectomy. Dr. Zink’s speculation regarding joint angles cannot be applied to, and isn’t discussed in, the article cited regarding increased incidence of cranial cruciate ligament rupture in gonadectomized dogs.

Anyway, I found it an interesting read.

[Journey]

The rebuttal was part of the thread that I linked for her.

 

Rave

That said, there are no REAL dangers to spaying before maturity, as has been the practice for quite a long time now.

do you have any scientific documentation to back this claim up? Just curious, thanks!

[gcv-border]

I waited until 14 months to neuter my BC based on advice from local agility people and Chris Zink's article.

 

Having said that, I now realize that there has not yet been a truly scientifically controlled study to answer this early neuter/growth plate controversy. Another bit of info I got from my vet -- smaller dogs mature faster (i.e. growth plates close by the time they are 8-10 months old) and the growth plates in a large breed may not close until close to 2 years of age. Therefore I see the type of breed as a variable that should be taken into consideration when discussing early neutering and growth plates.

 

I agree with Journey with regard to if you wish to, and are able to, manage a bitch in heat with an intact male in the house on whether you wait to neuter until 12-14 months of age.

 

Jovi

[topnotchdog]

This is a 2007 literature review trying to consolidate and interpret the (relatively scanty) information that's out there on your question. http://www.imom.org/spay-neuter/pdf/kustritz.pdf

 

B.

 

I received an article recently that said that it was potentially dangerous to spay or neuter at a young age. This article suggested waiting until the dog was at least 14 months old, or through puberty. As I am hoping to get a puppy, this is an important consideration for me. I did a search for this topic, but did not come up with anything here. Does anyone know about this? I could copy and paste the article here if anyone wants me to.

Thanks

D'Elle

[rushdoggie]

You just have to weigh your options.

 

To me this falls into the: "might not help but can't hurt" pile. We know that sex hormones have many roles to play in determining how an animal (including us) will grow, mature and develop. It makes sense to me that if my dog is destined for a lifetime of work or athletic games, that I want to ensure I don't tinker with that development.

 

I am certain I can keep an intact dog safe from creating an unwanted pregnancy/getting pregnant. Its a bit of a PITA, but I can manage it for the time it takes for my dog to be 100% physically and mentally mature. I wouldn't have more than 1 intact animal at any one time, so thats not an issue either.

 

Therefore, there's not a risk for me, and I would choose to wait.

[juliepoudrier]

^^I think this has always been the key. For the average pet, I doubt that early S/N makes a huge difference, especially in the grand scheme of things and when weighed against the real risk of unwanted pregnancies and the resulting litters.

 

If you (the general you) are responsible enough to keep your intact dog from being accidentally bred (or accidentally breeding another), then there's certainly no harm in waiting until an age with which you are comfortable to neuter your dog.

 

As far as dogs going through shelters and rescues are concerned, I think any risks associated with early S/N are FAR outweighed by the benefits gained of not having another breeding animal on the loose in the world.

 

FWIW, I have multiple intact dogs and don't neuter my males before they are 2. But then again, I am willing to deal with the PITA part of keeping bitches in heat segregated from intact males, and making sure that none of my intact dogs are ever allowed in a situation where they could be accidentally bred.

 

So to the OP the real question becomes: How comfortable/sure are you that you can prevent an intact dog from breeding or being bred during the time between sexual maturity and when you choose to neuter? If you are confident that you can manage an intact dog, then there's no harm in waiting, and there might be a benefit. If you are not confident, then I don't think the preponderence of evidence suggests that you'd really do any lasting harm by neutering at a younger age.

 

J.

[Maja]

I find this article interesting:

 

http://www.naiaonline.org/pdfs/LongTermHea...euterInDogs.pdf

 

maja

[Gloria Atwater]

.............

I agree with Journey with regard to if you wish to, and are able to, manage a bitch in heat with an intact male in the house on whether you wait to neuter until 12-14 months of age.

 

Jovi

 

 

Not the OP to this thread, but since I weighed in, too, I'll say thanks, all, for the interesting and very informative discussion.

 

Hubby and I will have to confer about our Aussie girl, since if she's allowed to come into heat, part of the management would fall on him, as I work in town two nights a week. Our dogs share the yard and sleep in the house, and crates are available, but hubby works out of our home office, and thus would not be able to manage 24/7. So, we'd have to fit up our only (and hitherto never-used) kennel to keep SOMEbody securely under lock and key, those two nights where I'm at work and he's on the computer and phone.

 

We do want this little girl to work, when she's grown, though, so we'll ponder. I spayed my Gael at 6 months and honestly don't know if it's made a difference or not, now that she's 14 months. She's a slender, whippet-like little dog, but she may have been like that even if we'd waited to spay her. In years past, we never gave it any thought, just spayed our girls at @ 6 months and they lived active, hard-working lives.

 

It's hard to really judge, I guess, and confusing to contemplate, with evidence going both ways. Thanks again for everyone's input.

Cheers ~

 

Gloria

[D'Elle]

Thanks, all, for the replies. My male is neutered and I am confident that I can keep the pup from being bred, so I will probably decide to wait until at least 14 months. Thanks for the links to the other threads and articles as well - very helpful.

D'Elle

[Rave]

Just so that you're fully informed, there is an increased risk of mammary cancer if you wait to spay your female after her first or second heat compared to spaying before first heat. Not a huge risk mind you, but still something to be aware of when making an informed decision. Suggest you go find this data or actual report online and not automatically believe everything you read here. ;-)

 

edited to remove guesses at risk percentages

[Journey]

Time out...let's make sure the numbers we quote are accurate. Here's a portion of the linked site (above) with their conclusion, data and numbers - there is a tremendous difference in .08% vs 8%

 

Mammary Cancer (Breast Cancer)

Mammary tumors are by far the most common tumors in intact female dogs, constituting some 53% of all

malignant tumors in female dogs in a study of dogs in Norway15 where spaying is much less common than in

the USA.

50-60% of mammary tumors are malignant, for which there is a significant risk of metastasis16. Mammary

tumors in dogs have been found to have estrogen receptors17, and the published research18 shows that the

relative risk (odds ratio) that a female will develop mammary cancer compared to the risk in intact females is

dependent on how many estrus cycles she experiences:

 

# of estrus cycles before spay Odds Ratio

None 0.005

1 0.08

2 or more 0.26

Intact 1.00

The same data when categorized differently showed that the relative risk (odds ratio) that females will

develop mammary cancer compared to the risk in intact females indicated that:

Age at Spaying Odds Ratio

29 months 0.06

30 months 0.40 (not statistically significant at the P<0.05 level)

Intact 1.00

 

Please note that these are RELATIVE risks. This study has been referenced elsewhere many times but the

results have often been misrepresented as absolute risks.

A similar reduction in breast cancer risk was found for women under the age of 40 who lost their estrogen

production due to “artificial menopause”19 and breast cancer in humans is known to be estrogen activated.

Mammary cancer was found to be the 10th most common cause of years of lost life in Golden Retrievers,

even though 86% of female GRs were spayed, at a median age of 3.4 yrs10. Considering that the female

subset accounts for almost all mammary cancer cases, it probably would rank at about the 5th most common

cause of years of lost life in female GRs. It would rank higher still if more female GRs had been kept intact

up to 30 months of age.

Boxers, cocker spaniels, English Springer spaniels, and dachshunds are breeds at high risk of mammary

tumors15. A population of mostly intact female Boxers was found to have a 40% chance of developing

mammary cancer between the ages of 6-12 years of age15. There are some indications that purebred dogs

may be at higher risk than mixed breed dogs, and purebred dogs with high inbreeding coefficients may be at

higher risk than those with low inbreeding coefficients20. More investigation is required to determine if these

are significant.

In summary, spaying female dogs significantly reduces the risk of mammary cancer (a common cancer),

and the fewer estrus cycles experienced at least up to 30 months of age, the lower the risk will be.

[Rave]

Thanks for the actual numbers. As I wrote, I was going off memory from years ago. I'd hope if someone was actually trying to decide that they'd do the research and find the actual data/report, and not rely on random, sometimes unsubstantiated comments on a bulletin board.

[Alchemist]

OK, I'm probably wading into things that I don't understand as well as I might (and DISCLAIMER, I am *not* a toxicologist), but having taught some very elementary "risk assessment", I think it's worth sharing some definitions of what is meant by "relative risk" and "odds ratio".

 

Let's say you have a group of female dogs. Some of them have been spayed, others are still intact. Of the spayed dogs, "a" dogs develop the type of cancer in question, and "b" do not. Of the intact females, "c" develop the cancer, and "d" do not. (We could put this into a matrix - hope the formatting works! rats, doesn't look like I can get it to format right. OK, just imagine this as a table with two rows (plus a header) and two columns of data)

 

with cancer without cancer

spayed a b

not spayed c d

 

 

The "relative risk" is defined as (a/(a + b ))/(c(c + d)). Here the numerator represents the fraction of spayed dogs who develop the cancer, and the demonimator reflects the fraction of intact femailes who develop the cancer. If these two ratios are the same, the odds of developing cancer would not depend on whether a dog had been spayed, and the relative risk would be 1.0. Above 1.0, the higher the relative risk, and the more the data would suggest that there's an association between spaying and cancer.

 

"Odds ratio" is defined as the cross product of the entries in the matrix: odds ratio = a*d/(b*c) . It's similar to, but not identical to, relative risk. Numbers above 1.0 suggest a relationship between exposure and risk.

 

It's possible that what this study is describing is something else altogether, called "attributable risk". This is defined as (a/(a+b )) - (c/(c+d)). This is the difference betwen the odds of having the disease in a dog that was spayed and the risk of cancer in an intact dog. An attributable risk of 0.0 would suggest no relationship between spaying and risk. But... note that an "attributable risk" value of 0.08 would translate to an eight percent increase in risk (once you convert fractional increase to percent increase).

 

Hope this helps more than it adds to any confusion!