The chicks and my hens got along fine for weeks until yesterday when I opened the coop and the chicks we're all bloody. The hens pecked all the skin off their backs from mid back to tail. I had to cull all the chicks because they were badly injured. Upon doing some research I found out that the ISA Brown is known for being aggressive so I have decided that they will be butchered, since there are only the two, with my meat birds in a month. We are taking the fall and winter off of having birds so I can relocate the coop and getting things setup for a new flock in spring.