What are the benefits of getting your dog neuterd?

I have 2 male dogs that have yet to be neutered (an 8-yr-old terrior mix and a 1-yr-old Chihuahua. Part of why they haven't got fixed yet is because there is no immediate need for it (we don't own any female dogs and they don't mingle with unspayed female dogs). I read in a dog magazine once, that getting your male dog fixed is of good since it can lower their risk for prostate cancer and lower their aggression level. Is it true?

Yes.You can find all this information at your vet's office, so you don't get the opinions of the not always so bright people on yahoo answers, but some real sound scientific advice.

Yes. It can also reduce the risk of roaming and thus, the risks of being hit by a car or getting into dog fights. It reduces the risk of std's if they come into contact with a female who has them- such as brucellosis.

No, it's not true.The only aggression that MAY be lowered is male-male dog aggression.Some studies indicate that it may RAISE the risk of prostate cancer.Do some research on the pros and cons of netuering, and make up your mind based on what is best for YOUR dogs and YOUR situation.

Yeah, it really helps. I had it done to my dog and now he's really relaxed and never gets agitated ( where as before he would bark at every single little thing that moved!!) he still loves walking and stuff so it doesn't completely chill them out

I would not be overly concern about Altering your Dogs in your circumstance. Unaltered males also generally grow taller, have a higher metabolism, and are more active. You just have to listen to them howl a few times a year if they don't mate!

yes, it is true that is lowers the risk of cancer and aggression. the testicles produce testosterone which can cause aggression and it also helps to calm the dogs as well.

What works for one is not always right for the other. If you don't need to get it done then i think it would be better to leave well alone.

yes it is true and it may also keep them from marking their areas