Discussion on Spaying and Neutering Dogs

A 2018 article in Psychology Today by Dr. Stanley Coren claims that neutering dogs causes

increased aggression. After reading the article and the cited works, I was confused. I had always

thought, along with many other dog professionals, that neutering assists with certain dog-to-dog

behaviors and with urine marking. I also support the practice of “fixing” our pets from a

population control standpoint. I have witnessed hundreds of dogs being spayed and neutered

through dog rescue and rarely (as in two dogs) noticed a change in behavior afterwards. Many

experienced dog trainers agree that altering helps some behaviors like dog-to-dog aggression,

marking, and mounting behaviors. Bob Maida, dog trainer of forty plus years, had this to say

about spay or neuter causing aggression, “It's just coincidental…those spayed females via the

elimination of progestin may move on the aggressive end…many years ago veterinarians used

female hormones to treat aggression but they stopped because it was cancer inducing. Neutering

cuts down on testosterone so to say it increases aggression doesn't make any sense... Those

anecdotal cases are just coincidental.” Many trainers believe neutering can assist with dog-todog

aggression issues but not dominance towards humans. There are other experienced,

respected dog trainers believing that neutering does cause increased aggression in male dogs.

After reading an article that questioned what I thought to be true for years, plus all the responses

to that article, I decided to do a little research for myself. I used scientific journals to research

studies on spay and neuter, including the two articles Dr. Coren cited for his statement article

“Neutering Causes Behavior Problems in Male Dogs.” Read my discussion and critique here