i use aviform Ultimate , i only used it for the vitamins , i liked the mollases based one better , my young birds havent needed any treating or ailed all season only just treated them last week for 1st time for pre racing. As for does it work i say it must be , but my flock are always treated by my vet 90% of the time its canker related other illnesses ride on the back of canker , good immune systems create better birds that dont ail .