I have bantams that weigh 1.5-3.5 lbs. All sick hens received the same dosage every 12 hours until they ceased to show symptoms. I used the syringes (1cc=1ml) I received from my avian vet. The vet assistant told me to use 1 cc or 2 cc if mixed 50/50 with syrup. I found that 1 cc cleared their...
I prefer using syringes over waterers when chickens are that sick. 1 cc of Denaguard every 12 hours clears up most respiratory issues. Some diluted liquid St Johns Wort will build the immune system.