Age of neutering controversy

[BostonRott]

In another thread, the topic turned to the age at which to neuter a puppy. I mentioned the study linking age of netuering to osteosarcoma. Here's the data:

Influence of Gender and timing of Gonadectomy on risk for appendicular bone sarcoma in Rottweilers

Cooley DM, Beranek B, Glickman LT, Waters DJ.
Departments of Veterinary Clinical Sciences and Veterinary Pathobiology Purdue University, West Lafayette, IN 47907

Background: The role of sex hormones in bone sarcomagenesis has not been extensively studied. In a previous study using the Veterinary Medical Database (VMDB), Ru et al. (Vet J 1998:156 ??-39) found a significantly increased risk for osteosarcoma in castrated males and spayed females compared with sexually intact dogs. However, this VMDB-based study could not evaluate whether age at neutering significantly influenced osteosarcoma risk. Purpose: To determine if gender or lifetime duration of gonadal exposure influences the risk for appendicular bone sarcoma in Rottweilers. Methods: Data were obtained from owners of 746 purebred Rottweilers as part of a nationwide, population based study. Each dog owner completed a questionnaire regarding gender neuter status, age at spay or castration, bone tumor occurence, age at diagnosis, current vital status and age of death. The incidence of appendicular bone sarcoma per 1000 dog years at risk was determined for intact males, castrated males, intact females, and spayed females. The relative risk (RR) and 95% confidence limit of appendicular bone sarcoma was calculated by dividing the incidence rate for each gender-neuter category by the incidence rate for intact males (reference category; rr=1.0). For males and females, the influence of lifetime exposure to gonadal hormones on bone sarcoma was determined by comparison of the incidence of four subgroups stratified by age at neutering. Results: Appendicular bone sarcoma affected 111 of 746 (14.9%) Rottweilers. The RR for bone sarcoma was 1.64 for castrated males, 1.36 for spayed females and 1.04 for intact females. Females spayed at <1 year of age had a significantly increased risk for appendicular bone sarcoma compared with intact females (RR=2.21). Similarly, males castrated at <1 year of age had a significantly increased risk for bone sarcoma compared with intact males (RR=3.12%) Conclusions: In this population-based study, Rottweilers that underwent gonadectomy at <1 year of age had a significantly increased risk for bone sarcoma. These observations may be explained by either a direct effect of sex hormones on skeletal homeostasis or by indirect effects on body conformation or physical activity. Alternately, confounding factors unique to dogs that undergo early spay or castration may account for this association.

*********

So the interesting twist on this question becomes are rescues, who mandate that anything through their doors be neutered (no matter the age) setting owners up for higher risk of osteosarcoma with no input from the potential new owner??

As a breeder who has sold over half her puppies to those who have lost dogs to cancer, and as one who has lost a dog to cancer, I can't see forcing people to accept higher risk of something as devestating as bone cancer because of some arcane policy.

Prior to this study, my recommendations to owners were to neuter males around 18 months (unless they had behavioral issues) and to spay females before their first heat. After reading this, I now recommend the females to not be spayed until after their first heat.

The above study lists the incidence of osteosarcoma in Rottweilers as 14%. The following info lists a far lower risk of mammary tumors in the female who has undergone one heat cycle:

"A female puppy spayed before her first heat cycle can expect never to develop a mammary tumor of any kind. The incidence of tumor development in this group is nearly zero.

If she is allowed to experience one heat cycle before spaying, the incidence rises to 7% (still quite low)."

Source: http://www.marvistavet.com/html/body...__canine_.html

I truly don't understand why a dog's origin (breeder, puppymill, orphan) should determine it's controllable health risks. By controllable I mean that if something is linked to age of neutering, and the animal is still intact, then this is a controllable factor.

[Judi W]

There is also reviewed data that prostate cancers are more common in neutered dogs than in intact dogs. This should not be confused with the enlarged prostrate that occurs in older dogs. Although the cry for neutering promotes that it prevents testicular cancer (of course something cannot become cancerous if it isn't there) however testicular cancer is quite rare, more so than prostate cancer.

A knife does not substitute for good animal husbandry.

[BostonRott]

I guess what I really don't understand is that both rescues and breeders claim to go through extensive screening processes and educate their new owners. So why is it tabboo for a rescue to place an intact dog but it's ok for a breeder?

I realize that no screening process is perfect and yes, some will slip through........but after seeing so much heartache due to dogs lost to cancer, and the public not understanding why such senseless things happen.......if we can give them a better chance against cancer (later neutering), why not??

[poohbearsmom]

Originally Posted by BostonRott

I guess what I really don't understand is that both rescues and breeders claim to go through extensive screening processes and educate their new owners. So why is it tabboo for a rescue to place an intact dog but it's ok for a breeder?

I realize that no screening process is perfect and yes, some will slip through........but after seeing so much heartache due to dogs lost to cancer, and the public not understanding why such senseless things happen.......if we can give them a better chance against cancer (later neutering), why not??

Clap clap clap clap clap. Great article, Gretchen... Things that make you say, "hmmmmmmm"...

I guess people can't be taught (or possess common sense enough) to what lengths they need to go to in order to keep accidents from happening... sigh... as I witnessed in the vet's waiting room on Friday; some people think that sanitary panties act as a chastity belt better than, oh.... separation during a bitch's heat cycle... and now an 11 year old silkie terrier pays the price for her owner's stupidity.

I've not been a fan of early neuter/spay... and now I'm less of a fan of the practice. I am, however, a big fan of education and responsible action.

[RottiMomCT]

Originally Posted by BostonRott

So why is it tabboo for a rescue to place an intact dog but it's ok for a breeder?

I realize that no screening process is perfect and yes, some will slip through........but after seeing so much heartache due to dogs lost to cancer, and the public not understanding why such senseless things happen.......if we can give them a better chance against cancer (later neutering), why not??

Because rescues rarely know the history of the dogs giving birth in rescue or the litters of pups they end up with. They spay and neuter to reduce the POSSIBILITY of someone saying "OOPS, we forgot to spay Flluffy and now she's pregnant...oh wait, we'll call the rescue we adopted her from, they'll SURELY take the puppies!".

YES, rescue CAN follow up and ensure the adopters have gotten the dog spayed or neutered, but many times, adopters just don't want to be bothered and do not want to spend the $$ to do it...rescue takes care of that one step for them - yet they are perfectly willing to hand over between $200-350 as an adoption donation to defray the cost of medicals the dog needed prior to adoption, including spay or neuter...go figure!

It's the easiest way to guarantee that the rescue dogs are not going to be bred 'accidentally' or on purpose...spay or neuter before they leave rescue.

[Patty1231]

Okay, not to be argumentative - just trying to full understand. Rottweilers are known to carry a high risk for cancer to start with. Only 15% of rotties actually develop bone cancer, so a 3x increase within that percentage looks high. However, does this justify not spaying/neutering shelter/rescue dogs who I would think carry a much higher risk of unwanted litters than actually developing bone cancer. I'm thinking the neuter/spay decision would be less of a point with responsible owners who purchase from responsible breeders. Rescues, in general, may be close to that in that they do pretty detailed screeening of adoptive families. But shelters will give a dog to just about anyone - I would think mandatory spay/neuter would be essential there.

[Judi W]

Is the assumption that a rehomed dog is going to be running at large and at risk not just to reproduction, but being hit by a car, getting involved in biting incidents and so forth just as it might have been before being rehomed? If that assumption has basis in fact, then the entire idea of placing dogs back out into the community itself should be re-examined.

[Patty1231]

Originally Posted by Judi W

Is the assumption that a rehomed dog is going to be running at large and at risk not just to reproduction, but being hit by a car, getting involved in biting incidents and so forth just as it might have been before being rehomed? .

Good point, but none of these instances involve monetary outlay from owners. Unfortunately, this is often a deterrant which is eliminated by the dog being spayed/neutered prior to leaving the shelter. Also, these other examples do not produce more puppies likely to end up back into the system or continuing bad blood lines.

[Judi W]

I am going to continue with the devil's advocate questions

Patty,
Sorry, but that confuses me. Are you then saying that adoptive homes are not expected to take care of their animals if it is going to cost money? How does proper confinement cost money? How then to justify placing dogs that it is known are going to have medical care needs beyond feeding and vaccinations? What then is the point of applications, home visits and all that screening we hear about? Is that process without substance? Should any dog, intact or desexed be placed in a home where it is expected the dog will be running at large and where care will be neglected if it involves spending money? Are those placements simply so it can be claimed that dogs have been rehomed?

[Patty1231]

Originally Posted by Judi W

What then is the point of applications, home visits and all that screening we hear about?

The above takes place with Rescues, which in my original post I likened to being just about on par with responsible breeders in regards to placement. All this does not take place with Shelters, which is where I got Perle and where many others obtain their dogs. At best, they give a 10-day waiting period (although I've never heard of this actually being carried out - myself and others have always walked out with the pet the same day). No background checks, no calls to vets, etc., etc. Only with Rescues do you see this taking place. I believe it would be best to neuter/spay all animals leaving shelters. Animals placed by good Rescues are a different story, where responsibility is verified (at least to the extent it ever can be). To me, the risk of unwanted litters from shelter dogs far outweighs the cancer risk. I'm not entirely convinced that Rescues don't also fit into this category but would be far less so than shelters.

[Judi W]

Is there a difference between shelters and rescue organizations. In some cases. some shelters desex before the dog is removed. Other's do not but offer very inexpensive desexing clinics. Few shelters put out as adoptable, dogs with knowable serious health issues. Most shelters charge a nominal fee of $50 to $60 for an adoption.

I know you specified good rescues as I am sure you agree there is no blanket statement that applies to all or even most rescue organizations. Some certainly do rehome intact dogs and some are more than willing to rehome dogs with knowable serious health issues. The adoption fees can be several hundred dollars or more. Some do a serious job of application process, others do not and give lip service only. Is it the assumption that a relatively "free" dog is less well cared for? You certainly give lie to that premise.

I think what needs challenging is that families taking in rescue dogs are irresponsible.

[Patty1231]

Originally Posted by Judi W

I think what needs challenging is that families taking in rescue dogs are irresponsible.

Most assuredly, as I have taken in a rescue dog and do not consider myself irresponsible in any way. My issue is the risk of unwanted litters versus the risk of cancer. Accidents happen, even to the most responsible owners. I just feel that the risk of unwanted pups outweighs the relatively small risk of cancer developing (15% of all rottweilers, a percentage of that risk being dogs spayed/neutered too early). And I would never belittle the impact of that small percentage when it happens, as I am currently dealing with that.

For me, I would still accept that risk, particularly in view of the fact that my breed of choice is particularly susceptible. I knew that going in.

[Bucky's Mom]

Originally Posted by Patty1231

To me, the risk of unwanted litters from shelter dogs far outweighs the cancer risk.

Any dog can develop cancer (intact or not) at some point in their lifetime - but only intact animals can reproduce.

I may be getting cynical but my "trust" in people and their ability to be "responsible" has not increased with llife experience.

So - I agree with Patty - at the risk of increasing cancer I will go with the surer risk of unplanned additional puppies.

[Silvermarten]

Conclusions: In this population-based study, Rottweilers that underwent gonadectomy at <1 year of age had a significantly increased risk for bone sarcoma. These observations may be explained by either a direct effect of sex hormones on skeletal homeostasis or by indirect effects on body conformation or physical activity. Alternately, confounding factors unique to dogs that undergo early spay or castration may account for this association.

So are there ongoing studies ?
It sounds to me that they 'suspect' it's hormone related but haven't been able to rule out other causes .

I've one of each . Bruce the rescue rott was neutered at adoption , estimated age 8 to 10 years .
Henry was neutered at 12 weeks . I'm very glad I had Henry neutered so young as his temperament turned out to be fearful and intensely prey driven . Add testosterone to this with maturity and I think we'd have had some very major behaviour issues to deal with .( we've had enough challanges as it is ) Just my thoughts
I look forward to more study info as it becomes available .

[Brooke&Ryan]

Gretchen,

Thank you so much for posting that study. I noticed when you mentioned it before, & was going to ask if you could post it. Very interesting.


Brooke