Yellow-backed duiker
These forest dwelling antelope feed selectively on plants or plant parts such as shoots, roots, leaves, and buds, but their diet is mainly made up of fruits. The yellow-backed duiker is more efficient at digesting poor quality food than most other duiker species. This allows them to eat large, low quality fruits. Their diet makes them very hard to keep in captivity as most domesticated fruits are not well suited to their low fiber requirements. They are considered concentrate selectors, meaning they eat "diets relatively low in fiber, have a well developed ability to forage selectively, a rumen bypass, a rapid passage and high fermentation rate for starch, and they frequently encounter toxins."
Elephants in Thailand
Elephants are herbivores, consuming ripe bananas, leaves, bamboo, tree bark, and other fruits. Eating occupies 18 hours of an elephant's day. They eat 100-200 kilograms of food per day. A cow (female) will eat 5.6 percent of her body weight per day. A bull (male) will eat 4.8 percent. Thus a 3,000 kilogram cow will consume 168 kg per day, a 4,000 kg bull 192 kg per day. As elephants can digest only 40 percent of their daily intake, the result is dung amounting to 50–60 kg daily. As elephants will not eat in unclean surroundings fouled by dung, their instinct is to roam to a new area.