problem with sex link pooper

[wenthenurse]

I have 8 chickens all different breeds but the sex link x 2 are my only birds with missing feathers around the pooper and one even looks like the rectum may have prolapsed. The poop on the ground shows no evidence of diarrhea or constipation. They appear healthy other than tier butts. I have washed their butts and placed electrolytes, vitamins and probiotic in the water.
Anyone else had a similar problem.