Example?

..................

Nervous behaviours.

When a dog is neutered it's hormones fluctuate madly for around 3 months before they settle. In that 3 months they can become very ary of things that they were never wary of before...and even more wary of things that they were worried about before.If you have a dog that barks and lunges out of fear...it could well make it worse.

I have seen quite a few young dogs neutered and they ALL have become much more nervy in the three months afterwards and have needed extra careful handling.They were all exceptionally well socialised and friendly.

This has however, only been something I've observed with young dogs...not with the older ones we've had neutered.

How young were these dogs? many go through a 'fear' period anyway which isn't connected to neutering.

The dogs were aged between 8 and 10 months.
Yes there is a fear period anyway, but it is also well known that dogs can become nervous post op. There hormones are all over the place so it's inevitable.

Yes, thats why I wrote "I personally would only castrate if there was a behavioural or medical reason for it"

I have had dogs castrated for both.

Sorry, missed that.

Actually it is not a theory, it is a fact, the testosterone/progesterone sex hormones act with the endocrine hormone to close the growth plates timeously. This biological fact has been proved by so many studies & independent research into the different growth patterns between early neutered siblings(it's not just dogs it's bitches as well)

For a vet to say he doesn't believe in a theory-when it is actually a biological fact, would be a reason for me to look for another vet.

When I was last speaking to a vet at the practice I go to(a young Australian as it happens)about early neutering, she said, although many vets call it a theory, it is a known biological fact that the two types of hormones are required for the growth plates & that she would never advise early castration except on medical grounds

Thanks for all the replies so far but the question wasn't about whether or not we should do it, more about when we do it how should it be done?

Wouldn't even consider it until after 9 months but will probably wait until then.

In terms of when..
There are vets who would say that it is best to do the op as soon as he hits puberty in order to stop any behavioural issues that may or may not arise with the hormone changes.
Other vets would say that is the worst possible time to do it because of the growth the dog is going through and as I said above, because of behavioural changes that can occur.

If I were to advise someone when to have their dog neutered, I would say that unless it presented with obvious behavioural problems that were as a direct result of testosterone...OR unless it had health issues relating to it's testicles still being in place, then it is best to wait until the dog reaches maturity. This is based upon seeing a number of dogs neutered, as I have said, all the youngsters had problems, yet the mature dogs sailed through the op.
I am not sure at what age a Springer is considered mature...I know for my breed it's about 3, so perhaps about 2/2 and a half for a Springer?

Neutering is very much a personal issue.