Final answer:
Citrus pulp is primarily used as livestock feed for its fiber and carbohydrate content. It is a by-product of the citrus industry, beneficial for the digestive health of animals.
Step-by-step explanation:
Citrus pulp is fed to livestock primarily as a source of fiber and carbohydrates. It is the by-product of the citrus industry after juice extraction, and it contains significant amounts of plant material, which include fibers that are beneficial for the digestive system of livestock.
Additionally, it contains some vitamins, such as vitamin C, though this is not the primary reason for its use as livestock feed.