Age to neuter

Male dogs receive testosterone in utero and another increase at sexual maturity.  Many of the male behaviors are there from birth. They then get what you could call a maintenance level produced by the testes throughout their life.  Marking and humping behavior is not usually affected by neutering.  Both my neutered males mark and hump on occasion.  Aggression is sometimes reduced by neutering but that is not believed to be true by everyone and it's not true for every male dog.  I think the marking indoors needs to be addressed as a training problem rather than a hormonal issue.  I also believe there would be no long term harm to your dog if you neuter now.  I don't have a problem with intact males and I don't have a problem with people neutering a male that isn't going to be bred or shown. 

JackieG

Marking and humping behavior is not usually affected by neutering.  Both my neutered males mark and hump on occasion.  Aggression is sometimes reduced by neutering but that is not believed to be true by everyone and it's not true for every male dog. 

I agree.  I have two intact males who are probably the two most social terriers I have met, and they are MUCH less aggressive than my two spayed females are!  Neither of them are overly big humpers, although Zipper will sometimes attempt to mount dogs who are too in-your-face, if walking away doesnt't work.

JackieG

I think the marking indoors needs to be addressed as a training problem rather than a hormonal issue.

For the most part I also agree with this, but....it can definitely be influenced by changes in the household, in which I often see a different between intact males and neutered males - if intact females are present, or if a male has recently been mated, in my experience he is likely to have an increased risk in marking overall for a little while afterwards.  This is normal, and most people with intact males (or who breed) are not surprised by this.  But many times, it can simply be housetraining.

I have a lot of dogs coming and going through my home regularly, and every once in a blue moon, there will be a specific dog that comes, that causes one (or both) males to mark indoors, but not my female who is generally my biggest "I'll-pee-on-your-pee" dog - she marks more than my males do outdoors!  My best guess is there is some olfactory/hormonal basis to it, although I've never been able to narrow down a pattern as to what type of dog it is.

I was going to wait until 16 months because I had read that it was best to wait until at least that age to help the dog fill out physically. However, at 6 months old Marley started getting the "male attitude" and didnt want to listen to me anymore...preferring to run around smelling where girls pee'd.

It was our training class one night that did it for me. We had to have them off leash for recall and instead of coming when I called...he decided to take off and wanted to play a game of "catch me if you can". I got so frustrated that night that he was scheduled the following week for neuter.
Complete 180* shortly after. He no longer cared about the girls, he is the best listener I have ever seen and it didnt stunt his growth one bit. He is a beefy, 80lb american boxer with about 5% fat.

This doesnt work for all though. Maybe I caught it right in time, maybe it was his personality, maybe I am blessed that it worked for me.

I'm late getting to this thread, but wanted to mention what we noticed with our Bullmastiff (now at the Bridge).  His parents were champion show dogs, and we intended to show him, so we didn't neuter him at a young age since he had to be intact for showing.

We showed him a couple times and soon realized we're not the kind of people who can commit to what that lifestyle requires.  By that time, he was 4+ years old, and being a worry-wart, I was afraid to put him through an elective surgery like that.  He eventually developed major anal gland problems that required gland removal surgery, so we had him neutered at the same time. 

In the years he was intact, we didn't have any issues with aggression, marking, humping, roaming, etc.  But I suspect that had to do with his overall personality and our management & training.  He was incredibly mellow, non-territorial, and didn't have any issues with dogs he encountered on walks, in our neighborhood, etc.  Actually, he did "mark" our neighbor's mini-Schnauzer once through our shared chain link fence --- the mini-Shnauzer was friendly, but very yappy at the fence line, and Tonka always put his nose down to Becker's nose, not making a sound in return.  One day, he turned and peed right on Becker's head, then walked away.  I think he was just tired of listening to him!

The only time we had a slight issue was when our neighbors had a relative visiting with a female dog who was in heat.  Tonka met her on a walk, and obviously noticed her condition (we walked on quickly).  The rest of the night, he whined at the door, begging to go outside.  Maybe he would've done that even if was neutered, I don't know.

Like others have said, I'm not so sure neutering solves all behavioral concerns.  I'm sure there are pros and cons to neutering at very young ages; each dog will probably have a different experience as a result of any decision.

About the bull mastiff....

I know that each and every dog is different, but I am assuming here since they are the same breed. My friend has 2 bull mastiffs and my neighbor has 1. All three of those dogs are intact and I have never seen them act aggressively, humping, not listening or try to mount any dogs or people.
They do tend to have a pretty mellow, whichwaydidhegogeorge attitude about them...

Do you think this is the breed and an exception to the rule of male dogs "growing up" and changing in how the act come a certain age?

Boxermom2Marley

Do you think this is the breed and an exception to the rule of male dogs "growing up" and changing in how the act come a certain age?

Your comment about their "whichwaydidhegogeorge" attitude was funny -- so true!  Our dog would pass by a dog who was jumping around excitedly, barking crazily, or doing some other high energy behavior, and Tonka would just kind of turn his head towards them slowly, gaze a moment, and turn back, sometimes looking at us as if to say, "What's up with HIM?"  He always seemed to act like he was too cool to engage in such shenanigans!