Zebras are plan eaters. The preferred forage is Aristida spp., Chrysopogonplumulosus, Dactyloctenium schindicum, Digitaria sp., Lasiurus scindicusand Sporobolus iocladus. Zebras are well adapted to eat herbs, have high-strength teeth, are very resistant, and the digestive system is very effective at extracting nutrients from grasses.
In ecosystems with high predation pressure, they may suffer heavier predation than do comparable ruminants, wildebeest, and buffalo, from the large cursorial predators, such as lions and spotted hyaena.
Grévy’s Zebras are predominantly grazers, with preferred grass species including Cynodon dactylon, Pennisetummezianum, Aristida adscensionis, Chloris virgata and Chrysopogonplumulosus. In stressed conditions, such as during times of drought, they eat Sericocomopsis spp., Salsola spp., Disperma spp.
These swards are often patches with high fiber grasses (e.g. Pennisetum spp.) that are not tolerated by domestic livestock. Consequently, with food availability becoming less predictable with overgrazing of areas by domestic livestock in recent times,
Free-standing water is a requirement of their diet. In much of their range, this is in the form of springs. Grévy’s Zebras drink in a four-hour time window at the middle of the day, probably to reduce the risk of predation water sources. In areas where people are, they are excluded from the use of water during the day and drinking shifts to night-time.
Plains Zebras: over 90% of its diet consists of grass the rest being herbs, which may be taken by accident. In Kruger N. P., Smuts (1972) recorded a list of some 50species of grass and eight herbs. The choice of grass species largely reflects the species available, but zebras show some selectivity: of seven main grass species, one, Panicum maximum, contributed 40% of the intake and the same preferences were shown all through the year.
Preferred grasses include Themeda triandra, Cynodon dactylon and Eragrostis superba. In extreme dry periods, they even go for corms and rhizomes.
Plains zebras seem to favor areas of short grass, especially recently burned areas with new growth. However, in the Serengeti, Plains Zebras are the first in a grazing succession. They move into the long grass, grazing it down by feeding mostly from the top stratum(using their incisors, rather than plucking) and thereby making it attractive to the Common Wildebeest and other more selectively feeding species.
Mountain Zebras select greener grasses with a high leaf: stalk ratio and little or no moribund material. They feed 40 to 80 mm above the ground, except when they observe the seed heads of some herbs. Protein levels of grasses selected generally exceed 5%.
Themeda triandra is the preferred grass species in the Mountain zebra, while Cymbopogon plurinodis, Heteropogon contortus, Setaria neglecta and Enneapogon scoparius are also eaten. Digitaria eriantha is eaten occasionally and Eragrostis curvula is used significantly only in winter when seedheads are eaten.
There are generally three main grazing periods during the day: a few hours after dawn, late morning, and from mid-afternoon to dusk.
Foals will nibble grass when only a few days old. Up to the age of about 14 weeks the foals of both subspecies eat the feces of adults, particularly that of their own mothers. They paw the feces and eat parts of two or three pellets, possibly to obtain a supply of the intestinal micro-organisms required to break down cellulose in their food.