You know your own friend more than any of us on here. But, I will say, once the cat is out of the bag, the cat is out of the bag. There isn't any turning back once you've told someone.
I've told 2 of my best friends and one went fine, and the other not so much. I've told this story before, and don't feel like repeating myself, so I'll keep it as brief as I can.
1st friend I had known for a few years at the time. In that time we had grown to be really good friends. One day we were discussing what kinks we had (and to be clear, I DO NOT see zoophilia as a kink, but rather a sexual orientation.) But, I mentioned that I was sexually attracted to animals and had done sexual things with them in the past. He asked a few questions about it. And, in the end he was like "You do you. Different folks, different strokes." He still occasionally asks if I plan to settle down with a girlfriend, because I don't think he quite understands just how zooey I am. But overall, nothing bad ever came of it. We don't really talk about it, but no harm was done.
2nd friend, it was a different story. I had known this guy for probably over 8 years at the time. At that time I was suffering through some manic episodes and ended up telling him about my orientation during a weak point in time. At first he seemed fine by it, he thought it was odd, but he knew I was an animal lover at heart. A week or two later he was frantically messaging me worried that I was hurting and raping animals. But after a somewhat lengthy conversation, I managed to calm him down. He was like, "yeah, I know you love animals. I should have known better than to freak out like that" well, that was the gist of the resolution to that conversation anyways. We hung out a few more times, but after 1 or 1.5 or maybe 2 months after I had told him, he 100% ghosted me. He still would hang out with other friends regularly, but he was completely done with me. I thought we were pretty damn close at the time, but... apparently not close enough to accept my zoosexuality.
So, if you do plan to tell your friend, be careful. I thought for sure that those two friends would accept me for me. They knew me, and I knew them. But, only 1/2 people I've told I'm still in contact with. Luckily the second now ex-friend, kept my secret as far as I'm aware. So, at least there's that.