My one black sex linked chicken had a prolapse and righted herself again. Now she has pasty poo and is pooping all over herself. Lately she ahs been acting funny and stands in the middle of the yard and has her head tucked up against her. She drinks but is not eating well. I noticed when I washed her rump that below the vent it was harder. When I cleaned her off yesterday I noticed the hard spot was bigger. What should I do?!?!?!?!

Could it be cancer? Sure sounds like some sort of lump, since eggs are not developed on the bottom, but the top, near the spine, to protect them from damage (I guess).

If she prolapsed, she might do with a dose of general purpose antibiotic to fight infection. Your vet might recommend which one to give. It would probably help if she were isolated, too, to prevent any picking. Tempt her with treats. Would she take a little boiled egg?

The prolapse was fixed on its own. Somehow she got it back in her herself. SHe will eat the horses sweet feed and only parts of the laying mash. She also likes worms. What type of anti.?

The antibiotic should be something to fight infection from a wound or trauma. What I have on hand now is for respiratory infection, so I'm not recommending it. A call to your vet should get you a recommendation at no cost. As a courtesy, you might offer to buy it from the vet's office.
If she will eat horse feed and parts of the layer mash, then offer her those. If you observe carefully, you may be able to see what she picks out of the horse feed. If it's just the oats, or the crimped corn, that's not as good for her as the pellets, but it will do. I just wanted her to be eating something while you're treating her.

She eats everything in the sweet feed. I noticed today that her balence is not the greatest. She walks with her haed ans neck contracted most of the time. She will act normal then stands.