our chick was about 3 weeks old we have had him for about a week he started coughing an sneezing a day or 2 after we got them.he seemed to be doing better yesterday then today he was doing it again with one of the other ones we went out to get tylan an a go shopping an got back about 3 hours latter an he was dead.i have giving the other 3 a shot of tylan 50 in there breast .25 cc how often should i do this an for how long?please any help we do not have a few hundred dollars to take them to the vet.