Mirabelle was a striped roan.

Mirabelle came to me with Bunty.
She was quite a nervous girl, and obviously was not used to being handled when she arrived here. She took longer to adapt than Bunty, and was a little less resiliant. Over time, she became much better and eventually became alpha of the girls. She was a gentle rat, and in her old age became a lovely, placid, caring girl. I could trust her in intros with new girls as even though she put them in their place, she was never aggressive.

Mirabelle developed a skin condition around midway through her life, and it never responded to treatment. I've never seen anything like it in a rat, and even the vet was unsure what it could be. I'd compare it to severe acne, as she basically had lots of small, pus filled boils all over one side of her flank. It only ever occured on one side, and never responded to antibiotics or special baths. Even draining each one of the lumps seperately and washing them all out only resulted in them coming back elsewhere on the area.
However, this didn't seem to bother her, and it didn't really spread beyond the original affected area. The vet thought it could be cystic in nature, and said the only real way to get rid of them was removal of the skin over the entire area. But even then, he said there was no guarantee they wouldn't come back, and it would be a big operation as it was a fair emount of skin to remove. As Mirabelle was fairly elderly at the time, I opted to leave her be as I didn't think she would recover from an op well.
She got on with her life relatively unconcerned by this problem, but as she aged, she became more frail and began to lose weight, just through her age. However, she lived in a group with gentle rats and I hoped she would live out her days and die naturally with her friends.

Unfortunately, Mirabelle's death was not peaceful or natural, and is something no rat owner should have to go through.

I had had my dominant, bolshy rat Luke castrated several weeks prior, and was hoping to try him living in with the girls. Castrated rats tend to take better to females than males when it comes to re-introducing them to rat company.
I had run them in neutral territory, and Luke had seemed fine. There were the usual scuffles, a little bit of fur puffing and sidling, but no serious aggression. Though in hindsight, Luke had seemed most interested in Mirabelle of all the others, but he still wasn't particularly aggressive.
I'd put them all into the cage, and watched them closely for a while. Again, the usual stomping about and scent marking from Luke, but this is to be expected, and he pretty much left all the other rats alone. A few hours later, I saw him curled up in the hut with another girl, seeming quite happy.

I returned from work a couple of hours after this and went to check in them, and found Mirabelle dead.
She had been ripped to pieces, blood was everywhere, and it was extremely graphic. I'll spare you the details. Luke sat calmly in the hut beside her, with blood on his legs and over his tail.
Mirabelle was covered in bite wounds, indicating Luke had just bitten and bitten at her until she weakened, and she'd either died of blood loss or shock. The larger wounds on her body I suspect he did after her death.
This is not a case of a rat dying naturally and the cage mates eating it to dispose of the body; there is rarely, if ever, blood in this case.
Mirabelle was elderly, and frail, and wouldn't have been hard to kill for a young, strong buck like Luke.
But this is not natural behaviour for a rat
Rats do not, as a general rule, kill other rats. The may fight, but they know when to stop and deaths are extremely rare. If they do occur, they tend to be accidental, and tend to be inflicted by a buck on another buck, or a doe on another doe. It is unheard of for a buck to do this to a doe.
It is thought that Luke has a brain tumour, or other kind of medical issue which causes him to be this aggressive, as it is definately not normal, and previous cases I've heard of where a rat kills another rat have usually resulted in the killer having mental illness.

Mirabelle was the unfortunate victim of a freak accident. I've never seen anything like it before, or since, and it is not something anyone could have predicted. Had I the slightest inkling that Luke would be aggressive, I'd never have left him in the group.
Strangely, he did not touch any of the other girls, or the other castrated boy (Hoffman) that lived in the cage; he only targeted Mirabelle.
This could have been because she was old and he sensed she was unwell. Some rats have much stronger instincts about these things. But either way, it is still not normal behaviour.

Mirabelle will be sorely missed, and her death was a tragedy, but it did show everyone that Luke's behavioural issues go deeper than simply being a hormonal teenager.

Why Mirabelle? After one of Marco Pierre White's past restaurants.

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