I know some instructors who never spay or neuter their pets because it interferes with an animal's natural functioning. However, I know others who do because they do not want to live with consequences of living with an animal in heat.
As we said to someone with the same question, if neutering or spaying an animal will allow for it to live in safety, then you must weigh the good and the bad to determine the better end.
For thirty years I sought God. But when I looked carefully I found that in reality God was the seeker and I the sought. -Bayazid al-Bastami