Coprophagy

Coprophagy [kŏ-prŏf'ə-jē]
-noun
eating of dung, or feces, considered abnormal among human beings but apparently instinctive among certain members of the order Lagomorpha (rabbits and hares) and in at least one leaf-eating primate (genus Lepilemur). It is thought that these animals obtain needed vitamins in this way. The diets of certain insect species, among them the dung beetles and dung flies, are primarily or exclusively coprophagous.
cop⋅roph⋅a⋅gous [kuh-prof-uh-guhs]
–adjective
feeding on dung, as certain beetles.
Origin: 1820–30; copro- + -phagous
Definitions retrieved from http://dictionary.reference.com/browse/coprophagy

While researching for a post on the topic of rabbits and hares (Lagomorpha) I came across this interesting bit of disgusting trivia. Apparently, rabbits (and hares) eat their first shit so that they can digest it in a unique part of their stomach and recover all of the nutrients from it before they shit it out a second time and are done with it.

"Lagomorphs produce two kinds of feces. The first kind is basically a first-cut, digestively speaking, from which some but not all nutrients have been extracted. This gooey black feces is eaten as soon as it is excreted, and then re-digested in a special part of the stomach. This second round of food processing extracts more nutrients, and the final-cut feces is in the form of small, hard pellets." (Lumpkin, 2000, paragraph 14)

Lumpkin, Susan. (2000) A Rabbits Tale Retrieved from http://nationalzoo.si.edu/Publications/ZooGoer/2000/4/arabbittale.cfm