what kind of dog is he ? i know a lot of people will say that unneutered males will mark in the house because they are unneutered. however i dont believe it has anything to do with not being neutered but rather that it is more a housebreaking problem. so whether he will now stop i am not sure he will. the hormones still remain in circulation for up to 2 months post surgery so if it is hormonal and not that he is poorly houseborken, it can take awhile before je stops.
i also think that most people associate behavioral changes with neutering surgeries. i dont necessarily equate them together. i believe that at the time of the neutering , which for most people is around 6 months of age, that at that time dogs are starrting to mature and their behavior will change naturally as they get older. since your dog is already matured, i doubt you will see too many, if any at all, behavioral changes. sex driven behaviors may diminish but i would think that is all you will see.
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