I think they are referring to data that are internal to their study, since they don't give a source for the 39% castrated vs. 61% intact dog distribution among the class of other types of tumors. I just sent you the PDF, so maybe you can tease that information out of the paper. They also have references for *cough* behavioral *cough* issues of castrated vs. intact dogs :devils2:.

LOL LOL on the *cough* cough* Will read it tonight after work. Tis Tax Season you know!

ZoE's vet is all about educating, and routinely shares issues he comes across with his patients.

This is a uterine horn, from a medium size dog, that was suffering from pyometra. The dog almost died. ZoE's vet performed immediate, emergency surgery and saved her, but shared the results and said this is why you should spay your pet.

Here's the uterine horn:

(I'm on my ipad so can only post one pic at a time.)

That dog clearly had to have suffered badly.

This is what a uterine horn should look like for a dog that size.

Here is a review article on benefits and risks of spaying and neutering written by Brennen McKenzie, the Skeptvet:

http://www.carodog.eu/wp-content/upl...PAV045web2.pdf

I'm pretty sure that this article is NOT behind a paywall. It appeared in a peer-reviewed journal (CABI Reviews), and here is the article's abstract (emphasis mine):

Neutering consists of removing the source of the hormones that control reproduction and determine secondary sexual characteristics. In dogs and cats, this is most commonly accomplished by castration or ovariectomy. While the primary purpose of neutering is to prevent reproduction, the procedure may have other physical and behavioural effects.

Epidemiologic research has identified many beneficial and harmful outcomes associated with neutering. A definitively causal relationship between these outcomes and neuter status cannot be accepted without consistent evidence from multiple studies of adequate size and quality. However, consideration of the possible health consequences of these associations is warranted when offering owners recommendations concerning neutering.

An evidence-based decision about neutering a particular pet requires integrating relevant research data with the veterinarian’s clinical expertise and the needs and circumstances of the patient and owner. It is impossible to precisely predict the outcome of neutering for any individual. However, existing research does allow some generalization about the magnitude and clinical importance of specific risks and benefits. Overall, it appears justified to recommend spaying all females not intended for breeding, because the procedure is more likely to prevent rather than cause disease. In male dogs, the benefits of castration are not so clearly greater than the risks. The evidence is also mixed regarding the risks and benefits of neutering dogs before 5–6 months of age, and so no strong recommendation for or against the practice can be made. However, it is clear that spaying female dogs before their first heat is preferable to spaying them later.

Cookie, my sweet 7 months old yorkie got spayed yesterday. I was told not to give her meds in an empty stomach coz it will cause her to vomit or nausea. She seem ok, I hope! She hasn't eaten since yesterday and just wants to be left alone. She likes to drink a lot of water, peed just 2x and went back to bed. What should I do if she still won't eat today. I'm worried she might get sick.

Her water drinking is a very good thing. If she hasn't been eating anything yet, you should call the vet for advice. Our Bella was also spayed at 7 months, and she was completely back to normal the day after her spay, as far as eating habits and energy level go.

Another article and another study
 

Thank you for the new article

Very interesting! It goes to show that you can't make a generalization for all breeds of dogs as to when and if to spay and neuter--each breed behaves differently. I hope that they collect and publish data on Yorkies!

Here is the direct link to the article:

PLOS ONE: Long-Term Health Effects of Neutering Dogs: Comparison of Labrador Retrievers with Golden Retrievers

Thanks Phil I would dearly love to get some yorkie research I don't understand with a very popular dog we don't have any yet.


The pendulum is starting to swing I think. And I hope that with all this research out there at some point we as dog owners will get a clearer answer. it kind of reminds me of the vaccination and vaccinosis question.


In terms of that research I would have hoped they would speak to pyrometra and mammary cancers in their summary of findings. As current and long term understanding is that these are two very important negatives with keeping a female intact.


Shrugs... oh well

From the above article
 

The most frequently mentioned advantage of early neutering of female dogs is protection against mammary cancer (MC) [12]. However, a recent meta-analysis of published studies on neutering females and MC found that the evidence linking neutering to a reduced risk of MC is weak [13].


And this is not the only study to find the evidence weak for Mammary Cancers....


I am left scratching my head on this. But of course we must remember there were no hall mark studies to show that in all cases for all breeds of dogs S+N is best done at 6months of age or so.

I just had this conversation with my vet. She told me that the studies have been about large breed dogs, but that it does make sense that spaying or neutering too young could have an adverse affect on the system. She said animals have sex hormones for a reason and not just for reproduction. She said if you think about it like a thyroid, this tiny thing affects soooo many things if something goes wrong. She also cited the studies that show the benefit of spaying and neutering. She suggested letting my puppy have at least one heat before spaying.