My hen had a weird calcified lump in her gut. I had it xrayed after she was looking unwell and her belly was huge and oddly warm to the touch. My vet said she was doomed and wouldn't last the week as she was 7 years old and the infection was really bad. He prescribed antibiotics which I gave her for 10 days and they helped but within a week she was sick again. I looked at many remedies before choosing what to do. I gave her an enema of coconut oil and bathed her. I brought her inside every night and put her on a hot water bottle. I put 1 ml of oregano oil into 1 litre of water for all the hens to drink during the day while she was out. I gave her watermelon sprinkled with probiotics every day before she went to sleep. I still gave antibiotics in the mornings for 10 days every third week. She did eventually die but it wasn't from the illness as I took her in for a checkup after 4 months had passed and the vet was astonished at her good health. He said that she had improved by at least 70%. My hen eventually died of old age and I was happy about that. I hope this helps someone who has a sick chicken. 
