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Question about neutering and aggression...

spike's mama
October 4th, 2008, 07:35 AM
We had Spike neutered almost three weeks the last week he has become terribly aggressive, biting, snapping, growling and barking. Is this a normal part of being neutered and the after effects of the testosterone going out of the system? And if long does it "usually" last?

October 4th, 2008, 08:28 AM
I have never heard of nor experienced any aggressive behavior related to neutering. I would suggest maybe a reaction to the anesthetic, but if it's been 3 weeks that seems pretty impossible.

Maybe describing the behavior more specifically would allow people to help you figure out what's going on?

spike's mama
October 4th, 2008, 08:51 AM
Okay...he is 13 months old. He will jump up on, bark at and snap at my fiance and my daughter. He has literally wrapped his mouth around my daughters arm/wrist a couple of times. He has gone after my fiance with teeth snarling while my fiance has been talking on the phone. He snarled at me twice when I scolded him for being head first in the garbage. This is the only time he has done anything towards is usuallytowards my fiance and daughter. When he is home with me during the day he is a completely different dog.

October 4th, 2008, 04:43 PM
Development of aggression post neuter is a documented experience in the links I'll post at the bottom, if you want to confirm it. But in the girls, not the boys. I would wonder if he is having some kind of painful post surgical complication that you should ask your Vet about?

An increase in reactivity toward humans with
strange (unfamiliar) dogs and in aggression toward
family members has been reported after OHE of bitches
in several studies.44-46 The reason for this possible tendency
has not been defined but may be attributable to
a decrease in estrogen and oxytocin concentrations,
both of which may exert antianxiety effects in some
species.47 This tendency also may be a breed-specific

From Determining the optimal age
for gonadectomy of dogs and cats, by Margaret V. Root Kustritz, dvm, phd, dact (