Tylan 200 (tylosin) is 200mg/ml and Tylan 50 (tylosin) is 50mg/ml, so it's 1/4th the strength.
Copy and Paste from:
http://www.scribd.com/doc/72234998/Plumb-s-Veterinary-Drug-Handbook-Sixth-Edition
BIRDS:
For susceptible infections:
a) For initial therapy in caged birds for upper respiratory...
What I usually worry about is histomoniasis (blackhead). Coughing is not a symptom of it, but secondary infections, both fungal and bacterial are. If you can, take your turkey to a vet ASAP. When they aren't drinking/eating, they go downhill very fast.
Tylan (tylosin) is more effective against...