Thank you 35Rem for the info.Never thought about it much spaying ,neutering when to do it .In my experience it has not made any significant difference and that is not to say the science is wrong.None of my first 4 labs and golden retriever lived past 11 fixed or not ,but the last was neutered at 6 months lived to 15 so I guess in the long run there was a gene pool in him that was exemplary .Thanks again for you're explanation .