Whitetail Deer Diet and Digestion

Feeding habits of whitetails vary from state to state and season to season.  Deer will eat just about any food they can find, (over 700 known plant species)  but they are still considered to be selective eaters.  They eat tender shoots and leaves from all sorts of trees, forbs, vines, plants, and bushes as well as the fruits, vegetables, nuts, seeds and grains these plants provide.  Protein rich sources (such as soybeans) are important to provide nutrients for body and antler growth, while carbohydrate rich plants (such as corn) provide quick energy.  Deer naturally find the correct balance of each in their diet as they graze.   

Certain minerals are also important for a deer to ingest to remain strong and healthy.  For bucks, it is most important for antler growth, one month before growth starts to intake vitamin a, vitamin d, calcium, and phosphorus.  For does, mineral intake during gestation is important to support herself and the fawn(s) inside her.  A doe will also need adequate minerals to produce good milk for her offspring. 

On average, each deer consumes 1 1/2 to 2 tons of food per year from the surrounding enviroment. In the spring and throughout the summer months, when green plants have become abundant, deer can/will eat up to 10 pounds of food per day.  During tough winter times a deer’s diet turns from selective to that of survival.  Their diets are forced to turn towards the more available woody browse of twigs, bark and branches of the local trees and shrubs as a staple.  During these time periods, it is possible for a whitetail to lose up to 30% of total body weight by winter’s end.  Especially in the deers more northern ranges.   

Typically you will not see a deer feed in one spot for a long time.  Because of their 4 chamber stomach design, deer will feed quickly and retreat to a safe place and regurgitate the food they just ate and rechew for digestion.  The first section, the rumen, is where food goes after it has been chewed and swallowed.  The rumen can hold over two gallons.  From the rumen, the food is brought back up into its mouth later for rechewing.  This is called rumination or chewing its cud.  The food is then ready to go to the second section of the stomach, the reticulum.  The third section, the omasum, is where the real digestion takes place.  The last section of stomach is the abomasum.  It is here where the food is pelleted and routed for exit.