How do I desensitize a fear aggressive dog to people?

No, because fear aggression is either comes from a weakness in temperament or a previous bad experience stored in its long term memory and when the dog is put in a similar position, reacts with aggression because it thinks there is a threat to its safety. Castration cannot correct a defect in temperament or control/correct a learned behavior, so of no use for the problem with your dog. Castration before puberty (six months or thereabouts), when the testosterone fuels hormone driven behavior in a maturing young dog, which is a normal and necessary part of its mental and physical development, can make a dog easier to manage, but the only guarantee is that it cannot reproduce.

I owned an eighteen month old dog born with a genetic predisposition to react with a degree of timidity around unknown, bullying or assertive dogs, castrated due to lump on a testicle. His reaction to dogs was unchanged after the procedure (though I have encountered castrated dogs that target intact dogs to assert their position over) It was quiet calm controlled confident leadership in everything I did with him and training that changed my dog’s behavior, as he learned to trust my judgment and handle situations that he thought were scary or somewhat unnerving.

You needn't castrate your dog to increase his confidence. Work on that before worrying about castrating him; http://www.dogtrainingbasics.com/Confide... If there is an AKC affiliated club in your area get in touch with them about obedience classes. This could help you also as some of the better trainers know how to handle a fear aggressive dog.

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