Graminivore

Not to be confused with Granivore.

A graminivore is a herbivorous animal that feeds primarily on grass,^[1] specifically "true" grasses, plants of the family Poaceae (also known as Graminae). Graminivory is a form of grazing. These herbivorous animals have digestive systems that are adapted to digest large amounts of cellulose, which is abundant in fibrous plant matter and more difficult to break down for many other animals. As such, they have specialized enzymes to aid in digestion and in some cases symbiotic bacteria that live in their digestive track and "assist" with the digestive process through fermentation as the matter travels through the intestines.^[2]

Horses, cattle, geese, guinea pigs, hippopotamuses, capybara and giant pandas are examples of vertebrate graminivores. Some carnivorous vertebrates, such as dogs and cats, are known to eat grass occasionally. Grass consumption in dogs can be a way to rid their intestinal tract of parasites that may be threatening to the carnivore's health.^[3] Various invertebrates also have graminivorous diets. Many grasshoppers, such as individuals from the family Acrididae, have diets consisting primarily of plants from the family Poaceae.^[4] Although humans are not graminivores, we do get much of our nutrition from a type of grass called cereal, and especially from the fruit of that grass which is called grain.^[5]

Graminivores generally exhibit a preference on which species of grass they choose to consume. For example, according to a study done on North American bison feeding on shortgrass plains in north-eastern Colorado, the cattle consumed a total of thirty-six different species of plant. Of that thirty-six, five grass species were favoured and consumed the most pervasively. The average consumption of these five species comprised about 80% of their diet. A few of these species include Aristida longiseta, Muhlenbergia species, and Bouteloua gracilis.^[6]

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  Red kangaroo eating grass
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  Horses grazing in a field
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  A capybara grazing at Hattiesburg Zoo

References

1. Graminivorous - Definition and More from the Free Merriam-Webster Dictionary
2. Connie, Rye (2013). Biology. Avissar, Yael,, Choi, Jung Ho, 1956-, DeSaix, Jean,, Jurukovski, Vladimir,, Wise, Robert R. Houston, Texas. ISBN 9781938168093. OCLC 896421272.{{cite book}}: CS1 maint: location missing publisher (link)
3. "Why Dogs Eat Grass—a Myth Debunked". Psychology Today. Retrieved 2017-10-17.
4. Picaud, F.; Bonnet, E.; Gloaguen, V.; Petit, D. (2003). "Decision Making for Food Choice by Grasshoppers (Orthoptera: Acrididae): Comparison Between a Specialist Species on a Shrubby Legume and Three Graminivorous Species". Environmental Entomology. 32 (3): 680–688. doi:10.1603/0046-225x-32.3.680.
5. Mundell, E.J. (9 July 2019). "More Americans Are Eating Whole Grains, But Intake Still Too Low". HealthDay. Archived from the original on 2 November 2021. Retrieved 31 May 2021.
6. Peden, D. G.; Van Dyne, G. M.; Rice, R. W.; Hansen, R. M. (1974). "The Trophic Ecology of Bison bison L. on Shortgrass Plains". Journal of Applied Ecology. 11 (2): 489–497. Bibcode:1974JApEc..11..489P. doi:10.2307/2402203. JSTOR 2402203.