Hormonal behaviors *can* become learned and therefore continue long after the hormones are gone; however, that's mainly only an issue with rabbits who are hormonal for at least a few months before they're fixed. As Blue eyes said, it can take as much as 6-8 weeks after the surgery for a male's hormones to dissipate completely (4 weeks for females) so it may be a while before you see results. Males reach sexual maturity around 3-5 months old, I believe, so he's definitely "at that age"... and his behavioral changes definitely sound hormone-driven. Don't expect him to revert back 100% to his personality as a baby - like humans, bunnies' personalities change and develop as they grow up. The completely irrational aggressive behavior is likely to fade as the hormones do, but he may continue to be pushier/more assertive in general. Also, behaviors that involve an external trigger (like food and/or cage aggression) have a higher risk of becoming "learned"/sticking around after the hormones are gone.
he was fine until after 3 hours he bit me out of the blue so foolishly I tapped him on the nose
I'm glad you realized your mistake! There is something you *can* do to punish a bunny, though - as soon as he bites, gently but firmly press his head to the ground and hold it for 2-3 seconds. This is how a momma bunny disciplines her kits, so rabbits instinctively know what it means. I made a video recently on handling/nail trims, etc... if you skip to about 13 minutes in, I talk about using this technique and attempt to demonstrate it (though it doesn't go well because Gazzles knew she was getting scolded for no reason). I actually misspoke when I said I hadn't used that on them in ages - I thought I must not have because it was the only reason I could think of in the moment for why it wasn't working (because Gaz was fighting me/pushing back so much)... Nala did let me demonstrate, though (probably because even when she's not actively being naughty, she knows she's still thinking naughty thoughts!
)... anyway, I went back to talking about other stuff and then - at about 16 minutes in - Gazzles hauled off and bit me while I was trying to apologize for making her be a demo bunny! When she bit me, I reflexively pressed her head down and that time she allowed it.
[ame]http://www.youtube.com/watch?v=R1qGcjM7syk[/ame]
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By the way, since you mention building a larger cage, don't forget to either wait until after he's recovered or leave yourself a way to limit him to a very small space (by keeping the old cage if you're replacing it or making it possible to section off a small part of the cage if you're renovating it) for a bit. It should be a small space without opportunity to jump - the ideal options are a 2W x 2L x 1H (in cube lengths) NIC enclosure, an XL dog crate, a store-bought "rabbit" cage (remove the little ledge if it has one) or an x-pen arranged to provide no more than 4-6 square feet of space.
I'm not sure how long males are supposed to be restricted for, but it's 7-10 days for females... I'm guessing it's less for males, though, as neuters are less invasive. Norman (my new guy) was neutered on Dec. 22nd and I adopted him on the 28th... no mention was made of restricting him (of course the HSPCA folks are very un-savvy about bunnies, so not being told that doesn't mean much - they looked at me like I was speaking a foreign language when I tried to get them to give me transition pellets), though he'd obviously been restricted at the shelter simply because of how pathetically small the rabbit/GP cages are. Your best bet is to ask your vet and stick to their recommendations for how long to keep his movement restricted.