# Metabolizable vs Digestible Energy?



## Pai (Apr 23, 2008)

I was looking at the calorie labels for some dog foods, and noticed they have different numbers under two columns: Digestible Energy and Metabolizable Energy. The calories listed for Digestible are higher than the other kind... what do these two labels mean, and what is the 'real' caloric value of the entire food?

For an example, look at this page's Guaranteed Analysis link.

Why don't they just put how many calories it has, period? Confusing....


----------



## briteday (Feb 10, 2007)

It's interesting that you found this information. Dogs can "digest" (pass something through the intestines and out the back end) just about anything. However, that does not mean that they can absorb any nutrients from whatever is passing through. So therefore, a more accurate calculation of calories is what can actually be "metabolized." Metabolized means the dog has the proper body chemicals to break down and utilize the ingredients listed.

A good example is corn. Dogs can digest corn but it provides very little protein absorbtion (yet the dog food companies are allowed to claim it as protein in the guaranteed analysis, it MAY have SOME protein, but dogs can't utilize it) and dogs mainly get only the carbohydrate (starch/sugar) benefit of it as a food source.


----------



## FriendsOfZoe (Aug 7, 2007)

I am surprised that a food with a real discrepancy between metabolizable and digestible calories would actually advertise that! Very very interesting link and question...and a very useful way for looking at dog food. Thanks, Pai and BD!


----------



## Kibblelady (May 6, 2008)

Pai said:


> I was looking at the calorie labels for some dog foods, and noticed they have different numbers under two columns: Digestible Energy and Metabolizable Energy. The calories listed for Digestible are higher than the other kind... what do these two labels mean, and what is the 'real' caloric value of the entire food?
> 
> For an example, look at this page's Guaranteed Analysis link.
> 
> Why don't they just put how many calories it has, period? Confusing....


Basically the difference is between how the food is designed to provide nutrition and how much energy is *actually *gained from the specific product. The ME is usually gotten from a feeding trial and is the reason why foods with a feeding trial having been conducted can be more reliable. A food can be designed to provide a high level of energy but fail to actually perform due to digestibility and absorbability issues.


An ME of 451 on a food that has a DE of 500 is actually VERY good and shows a very highly digestible and absorbable product.....check out some others and you may be shocked 

Cherri


----------

