Feed Ration Calculator

Species has the largest effect for a given weight -- switching between cattle, hogs, and sheep changes the baseline intake rate, the forage/concentrate split, and the protein and TDN targets all at once. Animal Weight is also a major lever: DMI scales up with body weight for any species, and stretched across its full 10-3,000 lb range it can move the total even more than a single species switch.

Species sets the baseline dry-matter-intake percentage, the forage-versus-concentrate split, and the crude protein and TDN targets all at once, because cattle, hogs, and sheep have different digestive systems and rely on forage to very different degrees -- hogs, for example, are simple-stomached and need a much higher share of concentrate feed than grazing ruminants like cattle or sheep.

Usually, but not without limit. Activity Level multiplies the baseline dry-matter-intake rate, so an active pasture-grazing animal is fed more than a largely stationary one at the same weight and species. It cannot push intake past the species' physiological ceiling, though -- an animal already eating all it can hold at a high target gain will show no further increase, which is the point at which a higher-energy ration, not more feed, is what the animal needs.

Treat them as planning-level estimates based on commonly published extension and NRC-style dry-matter-intake ranges, not a finished ration. Actual requirements vary by breed, forage and feed quality, body condition, reproductive status, and climate -- work with a livestock nutritionist or your extension office to formulate a balanced ration for your specific animals.