Hen went insane, incredibly violent to roo with no warning, ideas why?

[Kel60]

id like to begin this by saying the hen has already been culled to keep her from killing my only roo. i'm tying to understand why she might have suddenly gotten so violent.

she lived with four other hens and the roo(6 birds total all coturnix quail) in a 8 by 4 pen with lots of hiding spots. they've been perfectly fine for over a year since i hatched them. about four days ago she apparently woke up and chose violence. she was continuously attacking and mauling the roo. she'd grab his neck and body slam him around and when he'd get lose she'd grab his feet and drag him back. it was like she had dropped out of a bad teen slasher movie. i'm pretty sure she was going after the other hens to although i never saw it. one of them has a massive chunk of feathers missing around her neck. and the others are very ruffled.

but this poor roo, hes a sweety, and about the least aggressive roo ever. by the time i had enough, he was cowering in the hide box and wouldn't come out for food or water. when he tried she go after him again. if she realized where he was she run into the box and chase him out so she could rip into him more.

i wasn't going to let her kill him so i pulled her out. and after an hour observing to make sure i actually had the troublemaker i culled her. all is quite now, but i swear there all creeping around like their expecting her to lunge out of the darkness at them. the roo is traumatized. hes still shaking in the corner, and when i coaxed him out so he could see it was safe he was terrified and cowering against the walls. hopefully he calms down. hes tame enough he'll sit on my shoulder sometimes. i just don't understand why this hen might have gone crazy like this!

i gave her a good look over after culling her and it was definitely a hen. heavily specked chest with no red. i didn't have a late blooming roo.

any idea why this might have happened? i don't want to have this happen again if theres something i can do to avoid it.

 

[CovidtimeQuail]

I have no answers, just sympathy.

 

[Nabiki]

Wow. I've heard of them getting irritable when they're moulting or suddenly turning into bullies, but nothing that extreme.

I'm sorry I don't have any further insight for you. She went postal. :-(

 

[FloorCandy]

The only thing I can think is she started showing broody behavior, maybe she had been considering brooding eggs and he got too close and she laid into him, sometimes once they get something in their tiny brains, they just keep it up for no reason except it was what the last thing they remember doing and got stuck I. That mode. I’ve had hens walk past an egg and decide to sit on it for a few hours and when another bird walks by they chase them away.

 

[Fenrisulfr]

It happens quite often, this sudden turning.

It can be to much heat, to much light, another bird died and the order is re-organizing.

Also I just relized (first nature breed), that when a hen gets broody, she attacks the roo.
I reconstructed some of my incidents and propably some of my violent hens may were broody (without breeding) or on the edge of broodiness. Hens can get very mean in that period. And most times they don't really breed, but being broody territorial.

Sometimes I think, it's just, that some don't like each other ... dunno.
And yes, I also don't get used to it. It seems, that always the most beautyful bird is beaten apart ... .