Hi, Renee.
ODTBC is Ontario Dehy Timothy Balance Cubes, also marketed by Triple Crown as Timothy Balance.  https://www.triplecrownfeed.com/products/timothy-balance-cubes/  ESC is guaranteed to be at a safe level for EMS horses.

There's a document with the many abbreviations used on ECIR in Files:
https://ecir.groups.io/g/main/files/1%20Start%20Here/Commonly%20Used%20Abbreviations.pdf 

The Files are a valuable resource where you can find a lot of information. 
https://ecir.groups.io/g/main/files 
--
Cass, Sonoma Co., CA 2012
ECIR Group Moderator
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