I have a high privacy fence. My dogs never go out by themselves. My pets are all fixed- spare Buddy the Chiweenie who we are trying to get on scheduled to be fixed. She got extra upset when I said if he did well at the shows I would maybe even consider studding him out, providing all health and genetic tests come back clear. He is going into training pretty much as soon as possible. With a trainer who is very good with hunting dogs and has trained him full siblings from a different litter before.
No, the individual health and animal should be taken into account rather than broad brushes. I had a cat who would have died had we waited till she was fully grown to spay her.
Eury, that's my thought, and it's swapping over to us. I'm happy the culture of early neutering gets a bit more challenged now. I enjoy watching my dogs grow physically and mentally with each surge of testosterone and all others ^^°
It's a pretty common thought in the US that animals should be altered as young as possible to prevent health/behavior problems. I think a lot of it is pushed by various rescues/shelters who engage in that practice