Amid lap, I know your question is very old, but I have been traveling the same road recently and here is what I've found. You are correct there is a growing body of evidence and consensus among some vets that the absence of testosterone in castrated or aged male canines has profound adverse health effects. There is a vet in Florida, Dr. David Bieber, who is treating older large breed dogs. He is seeing tremendous overall improvements in their health through normalizing their hormonal balance. Unfortunately, he wants $2500 and a non-disclosure agreement from your vet to explain his protocols. I've been able to figure out what is the likely type of testosterone he is administering and the dosing guidelines. I've spoken with my local vet and shared the available information with him and he is in agreement about the use. Below are two links you may find helpful.
http://dogosterone.com
http://www.msd-animal-health.co.uk/Products_Public/Durateston/090_Product_Datasheet.aspx
Thanks ginger! I'm not trying to fix anything tho, I'm just trying to support his overall health. Low testosterone is directly related to prostate cancer in us old guys. Its has many physiological benefits. I know from personal experience. Natural testosterone cream reduced my blood sugar, triglyceride and cholesterol levels to a normal range. My depression lifted and my enegry levels increased. When testosterone is converted to DHT and estrogen it can be problematic. But there are safe and effective way to prevent that from happening.
I'm not considering testosterone treatment for my baby but I know that an imbalance of hormones can effect the body in many ways, not just sexuality.
My dog seemed healthy when I was feeding him standard store bought dog food. When I changed over to a high quality organic dog food I was simply looking out for him in the long run. It's the same kind of thinking with hormone levels. Im just looking out for him.
Maybe -if it ain't broke, don't fix it....?
If your dog is a happy, healthy, energetic good dog, then that's all the evidence you need to tell you he's doing just fine. Testosterone at too high levels can definitely cause problems, even cancers. And it might be hard for you to judge what is ok, and what is not.
I have known a few dogs who were neutered and still apparently, had enough testosterone still going on to even be able to mate and form a "tie" with a female in heat -even years after their surgery! So there must be still some testosterone going on -I would think as much as they need.