How aggressive is too aggressive

[Fuzzy Penguin]

We have to male rabbits- a mini lion and mini satin lop. They bonded together on the hour ride home in the carrier at age 10 and 8 weeks respectively. They are in a 2 story almost 6 feet liveable space and they are let out daily for supervised playtime in an 8 x 10 ft area (it's a hallway and we put different boxes out with holes for different running around fun, plus toys). The mini lion has gotten more and more difficult with being held or grabbed in any way over the past couple of months but both are trained to go in their cage with a treat- so that part is good but we can't trim Hershey (mini lion) nails. He has been humping Bolin (the satin) and I understand that this is domination behavior and natural and we ignore it unless it goes on for several minutes or Bolin seems particularly distressed. Yesterday the boys got into a row during playtime- fur was flying and I had to thump the ground repeatedly and throw a towel in to get them unlocked (I would have lost a hand reaching in they were quite at it). Now Bolin has an injury that looks like a bite mark. They both seemed fine after but saw this wound this morning, I don't know if he was bitten last night or if somehow neither I nor my daughter missed it when we were going over their bodies looking for injury. Both buns are now 4 months and 3 1/2 months old respectively. We took them to the vet a week after having them for a general check-up and he said neutering was only necessary if there was lot of aggression toward the other rabbit (or if one became aggressive toward humans and although Hershey doesn't like to be held- he is very friendly, hand feed, loves pets and climbs on your lap, etc.) Also the boys cuddle up together most of the time still. I have several questions:
1) When is it a lot of aggression? (I hate to have Bolin injured again but then again what if it is just this one time?)

2)I know once the main rush of hormones settles down so do they- is there a way to promote being held after that time (currently staying on the lap is promoted with treats but any attempt to grab hold and he's off!)?

3) Should we put a partition in the cage at night and have them together during the day or will this serve to push them further apart? or just general upsettedness as they do cuddle together a lot-
or would maybe having separate play time in addition to together play time be useful ( a small break from each other)?

4) I've been contemplating a bigger cage build that I may be able to do this next month - would adding some extra space help curb aggression a bit?
In the pics- Hershey is the white one with chocolate ears and spots, Bolin is the black one, he does seem to like rides on my dd back ;D

Thanks in advance for all opinions/suggestions!

 

[JBun]

First off, you need to find a different vet, one who actually understands rabbits. It is completely incorrect for a vet to say that neutering isn't necessary for two male rabbits that you intend to live together unless there's a lot of aggression. Which by the way, the fight you saw is considered a lot of aggression and is the type of aggression meant to severely injure or even kill the other rabbit. Hormonal male rabbits will almost always fight, sometimes with severe consequences including fatality.

Your rabbits need to be separated immediately or you could end up with a severely injured rabbit. If you were to keep them together, the aggression and fighting is only going to continue to escalate as they get more and more hormonal as they age. If you still want to have two rabbits that have a chance of bonding later, keeping them together any longer not only risks injury/death, but also can affect any chance you'll have of bonding them later once they are neutered, as rabbits can build resentment with another rabbit when fights are allowed to continue to occur. Whether or not you continue to allow supervised playtime is up to you, but I would only allow it if there was no chasing or humping, and they both enjoyed the time together.

You will need to examine the wound and keep a eye on it for any signs of affection or a lump forming. If the wound is bad, see a vet now. If an infection develops or a lump, get to a rabbit vet for treatment.

If you want them to be a bonded pair, separate them, get them neutered by an experienced rabbit vet, then you have to wait 4-8 weeks post neuter for the hormones to sufficiently subside before you attempt rebonding them.
https://rabbit.org/vet-listings/
http://www.bio.miami.edu/hare/opcare.html
https://www.cottontails-rescue.org.uk/information/bonding-bunnies/

They will also need a larger living space to live together as a bonded pair. Too small a space can lead to building irritation for some rabbits. Bonded rabbits need to be able to hop away somewhere for a break if the other bun is getting on their nerves. A puppy play pen is what a lot of house rabbit owners use. You can also use the cage with the puppy play pen if wanted.

With being picked up and held, the majority of rabbits detest it as it's not natural to them because it would only happen in nature if a predator got them. Some rabbits will tolerate being picked up more than others, a few like to cuddle but don't like the process of being picked up, but some the more you try and pick them up the more they distrust you, and will learn to avoid you and your hands at all costs. I would suggest to avoid picking up that bun as much as possible. The more you attempt to do it, the more he will avoid being around you or wanting to be near you. Instead, encourage him to come up to you while sitting on the floor or such, and allow him to do it on his own terms. Of course sometimes it is necessary to have to pick them up, but I would suggest avoiding it unless it's absolutely necessary, because each time you attempt it will impact any trust you are able to build with him by not picking him up.
https://flashsplace.webs.com/bondingwithyourbunny.htm