Hi Marko:
I've had similar issues with our 3. Yogi (10 male ), Mrg (9 female ) and BB (10 female ).
Yogi and Mrg pick on BB - used to be fairly frequently - and BB has a tendency when being picked on to scream blue murder
and can be heard all over the house, and we come running.
BB also has anal fissures and I think scent of "wounded animal" might spark this problem. Although sometimes they occur when she's showing no signs of anal issues.
Somewhere around Christmas, I came across an article suggesting using Rescue Remedy - suggesting that mixing 10 to 12 drops in a small 30 cc dropper bottle of distilled water and giving 10 drops or 1/2 cc 3 times a day to the animals with meals.
I started this back n February and it seems to be working for me. It was very slow to start seeing any results. It could have taken about 3 weeks to a month. Things have settled down considerably and they seem to be getting along much better. However, BB is still leary of the other two.
When I give this mixture to the cats, I mix it into their meals which are wet food which makes it easier to administer. It can be dosed using an eye dropper if you are using dry food.
Hope this might be helpful to you.