Feed companies are required to provide basic information on a feed bag. The name of the feed can be almost anything, as long as it does not state or imply any drug or medicinal claims that are not allowed by the USDA. The bag should indicate whether the feed is textured, pelleted, extruded, milled, and so on. The tag may also identify the type of livestock the feed is designed for and which physiological stage of the animal the feed is best suited (i.e., weanlings, lactating does, maintenance).
Each bag of commercially produced animal feed will list the amount of specific nutrients that are guaranteed to be in the ration. The nutrients that are guaranteed in the feed include crude protein (minimum), crude fat (minimum), and crude fiber (maximum). Moisture content may also be printed on the feed tag.
Protein — made up of amino acids that are referred to as the "building blocks" of the muscle — is one of the most important nutrients in the diet of animals and is typically the most expensive nutrient in animal feed. For maintenance, adult goats require 12 to 14% crude protein, while growing goats need 14 to 18% crude protein.
The energy in animal diets is usually expressed as total digestible nutrients (TDN). When you study a feed tag or label, TDN is not typically listed because it is difficult to determine. Instead, crude fiber can be used to estimate energy content in the feed. When the percentage of crude fiber increases, the digestible energy decreases. For example, when crude fiber is high (22%), the TDN value may be as low as 52%. (At 40% TDN, the animal will experience weight loss; a TDN value of 80% will allow the animal to reach its maximum genetic potential).
Fat has an energy value of 2.2 times the value of carbohydrate feedstuff (corn or barley). Thus, it can be used as an economical source of energy for animals. Including more than 5% of fat in the total diet of ruminants, however, may reduce the efficiency of digestion and reduce feed intake.
Some feeds may also include drug additives. A feed containing drugs must be labeled “medicated,” followed by the brand or product name. Medicated feeds will show the amount of each drug, the purpose of the drug, directions for use, and precaution and warning statements. Withdrawal periods must be followed when using these products on food animals.
