I had a cute Rhode Island White, about 7-8 months old who got sick a couple days ago. She was very raspy in her breathing, had a poopy butt, and became very sluggish in her movements. I brought her inside, tried feeding her electroylites, oatmeal, yogert, and put her under a heat lamp. She didn't survive the night. My question is, should I be doing something preventative to keep the rest of the flock from getting sick? I did bleach out the water containers and spread a layer of DE all over the coop. I noticed today one other chicken with what looks like the start of a poopy butt, so I gave the chickens a round of yogert/oatmeal/epsom salts. Should I also put them on anti-biotics just to kill anything they might have caught from the sick one? I don't want to lose my whole flock. This is my first batch of chickens (I have 8) and I've already lost another back in October who was fine one day and then very sluggish and slow motion the next day and died within 24 hours. My chickens have plenty of coop and run room and I keep it all pretty clean and use a combination of bedding pellets and wood shavings in the coop and nest boxes. I usually give the girls some yard time each day (or most days) and feed them fruit and veggie scraps along with their layer pellets...if any of this information helps? Any help would be greatly appreciated. I don't want to be overly paranoid, but I'd be more than happy to put the chicken on some sort of medicine for a bit to clear out their systems and save their lives. Thank you.