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9 Things You Didn’t Know About The Deer Stomach

Be amazed by the incredible deer stomach.


Now that winter is through, many hunters are turning their concerns from staying inside and keeping warm to heading out and doing work to improve their deer properties.

One common concern at this time of year is making sure that deer herds get enough nutrition. Currently, we're in a bit of a no man's land, between winter fat reserve and woody browse season and springtime food plot season. It's late enough that most bucks and does have exhausted the fat stores that they accumulated in the fall, and late enough that most woody browse sources on the ground are dwindling or gone, but it's not late enough yet that spring growth is a nutritional possibility.

RELATED: How To Approach Spring Food Plot Planting without Wasting Time and Money

Luckily, whiletails have extremely robust and complex digestive systems that allow them to adapt to just about anything.

Here are nine amazing deer stomach facts that you might never have known.

View the slideshow and see how many deer stomach trivia items you already knew.

1. It has four compartments 

Photo via welcomewildlife

This is one of the better-known facts about the deer stomach, but is still not as universally recognized as, say, the misconception that cows have four different stomachs.

In fact, cows and deer are both a part of the same mammal group - along with goats, camels, giraffes, and other animals - and both of them have a single stomach that is split into four compartments. Animals with these multi-compartmented stomachs are called ruminants, with the compartments being known as the rumen, the reticulum, the omassum, and the abomasum.

2. It can derive nutrition from cellulose 

Photo via microbewiki

Humans and other single, simple-stomached animals cannot digest many plant-based foods because our digestive systems can't process cellulose.

RELATED: How To Make An Irresistible Food Plot

Thanks to their ruminant stomachs, deer actually do have the ability to derive nutrition from cellulose, which is why they are able to subsist on little more than woody browse for the majority of most winter seasons.

3. It uses a fermentation process to digest cellulose

Photo via

So why are deer able to digest cellulose, beyond the simple fact that their stomachs have multiple compartments?

The reasoning is contained in a process that uses bacterial microbes located in the rumen stomach compartment to ferment plant-based foods and extract their nutrients prior to digestion. These bacterial functions do most of the work necessary to break down cellulose and pull nutrients from woody browse and other fibrous plant matter.

4. Deer often have to chew their food twice 

Photo via

Like other ruminant mammals, deer are able to break down cellulose thanks to their compartmentalized stomachs. However, since the bacterial microbes in the rumen can't always do all the work necessary to break down plant matter and pull nutrients out of it, deer often have to chew their food twice: first when they are eating their meals and eating it directly from trees, bushes, or food plots; second when the stomach regurgitates it, in fermented form, as what is called a "cud."

This second round of chewing helps to further break down cellulose compounds and unlock their nutrients. It is also the reason that ruminant mammals like deer are also sometimes referred to as "cud chewers."

5. The deer stomach digests some foods slower than others 

Photo via

While deer can digest plant matter with high cellulose content, that doesn't necessarily mean that it's the best thing for them.

Foods with incredibly high cellulose content - certain types of browse, for instance, such as the tougher, more fibrous browse produced by pine trees - are more difficult for a deer stomach to digest than others. This inequity of digestion speeds springs from the fact that not all plant matter is equal in terms of cellulose content.

6. Deer can starve to death with full stomachs 

Photo via

Because some types of plant matter take so long to digest and ferment, an excess of those types of more fibrous browse in the stomach can create a traffic jam of sorts that causes a deer to starve to death. Even if a deer eats a lot of woody browse, that doesn't necessarily mean he or she will be able to survive off of it. On the contrary, since fibrous browse takes so long to digest, a deer can feasibly eat it, but still die of starvation before the body can properly ferment the food and process the nutrients therein.

7. Deer try to diversify diets to avoid digestive jams 

Photo via thehindu

Because browse can cause a hold-up in the digestive process, most deer will try to avoid overloading on cellulose-heavy foods. Deer will actually try to avoid fibrous browse in search of healthier, more succulent and easier to digest foods.

Most deer will maintain diverse eating habits throughout the year, largely as a security measure to prevent their stomachs from overloading and being unable to process nutrients. Understandably, then, fat reserves are incredibly important in the winter when woody browse is just about all that is available. Deer at the end of the winter or beginning of spring will generally turn more and more toward fibrous browses, simply because they are starving to death and can no longer afford to be cautious.

8. The deer stomach can produce its own protein 

Photo via strengthguild

One of the coolest things about the ruminant stomach is that it can produce high-quality proteins. This process is, once again, managed by the microbes in the rumen, which use pretty much whatever is available - specifically amino acids and nitrogen reserves - to create protein chains.

Of course, deer must still eat protein, but this process helps to avoid deficiencies.

9. Deer digestive habits have to adapt and change with the seasons 

Photo via QDMA

Since deer eat different foods with each season, their digestive structures have to change as well.

For instance, the stomach that is digesting cellulose-heavy browse in the winter and spring and summer crops in the warmer months is not exactly the same. Certain factors in digestion - including the size of the rumen, the lining of the rumen, and the amount of saliva a deer produces - change from one season to the next.

However, this change is not instant. On the contrary, it usually takes about two or three weeks for a deer stomach to adapt, which is to say that most whitetails would not yet be able to derive nutrients from spring or summer forage.

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9 Things You Didn’t Know About The Deer Stomach