Iām so sorry to hear that TillyPeeps. My flock has been fighting the same respiratory illness for 3 years. Itās not from Dennis, his birds got it when they came here. Itās not Newcastle, influenza, or any of the fast killers, Iām thinking itās some kind of Mycoplasma but they donāt respond to antibiotics at all. However, the 3rd generation chicks are doing great, and although we had a few sniffles early on they seem to have much more resistance to the disease, whatever it is. Marans seem to be particularly susceptible, which is awful because itās one of my favorite breeds, and Tiger fought it for over a year before he died. What a sweetheart, it really hurts going out to the pen at dusk and not finding him waiting for me.