Feed Question (Mcals)

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From: Danielle McNeil 
Email: hossestogo@yahoo.com



Hi!  I have a question that kind of relates to the NRC book for figuring out
your horse's rations.

(Please (begging) don't reply to the email address listed above... I
 wouldn't want to intrude on my friend's generosity more than I have done so 
already with her computer --- THANKS!)

Anyway...

I am feeding my horse Equine Senior and burmudagrass hay right now.  However, 
the feed tag from Equine Senior does not list DE (digestible energy), TDN, or 
much of anything else energy-related except for a minimum crude fat %.

How would I go about figuring out what this feed's DE amount is based on only
crude fat, crude protein, crude fiber, and a slew of minerals and a vitamin? 
Or, do I need to call Purina? 

I figured out that based on crude fat % (listed as a minimum of 4%), the feed 
only provided 0.36 Mcal per kg. (Based on 9 Mcals/kg of fat).  How do I account
for the other sources of energy from this feed, such as carbos, etc.?
I can't think that a horse could live off of 0.36 Mcal/kg of E.S. per day?!?

Thanks ahead of time for any advice!

Danielle