Hello, and welcome!
My name is ***** ***** it will be my pleasure to answer your question. Birmans are one of my most favorites breeds! : )
Your handsome, furry boy sounds like a darling and I'm so glad he's mellow and does not urinate on anything or spray to mark territory. However, it is healthier for him if you were to have him neutered. Neutered males do not risk developing testicular cancer and do not want to roam, seeking a mate. According to statistics, male cats that are neutered tend to live longer than those that are not neutered.
At one year old, it's possible that your cat has not yet reached sexual maturity, and it is desirable to neuter a male before he reaches sexual maturity. Birmans typically reach full maturity (in general) at 3 years of age. However, most male cats typically become sexually mature at about age 6 months.
If your cat is a pure-bred, pedigreed Birman, with legitimate 'papers' showing his parentage 'line,' the only reason not to neuter him, would be if you were interested in breeding him with a female, pure-bred, pedigreed Birman and selling the kittens (or keeping them, depending on your preference). If this is not the case, neutering him would definitely be in his best interest, health-wise.
I hope this helped!
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