Dry Matter (DM): This includes all of the nutrients in the feed except the water.
Crude Protein (CP): The N content of the feed ingredient multiplied by 6.25. It includes both protein and nonprotein N in the ingredient.
Rumen Undegradable Protein (RUP): The protein in the feed that passes through the rumen with little change; it is not hydrolyzed by microbial enzymes in the rumen.
Rumen Degradable Protein (RDP): The protein in the feed that is hydrolyzed in the rumen by microbial enzymes. The microorganisms use these amino acids for protein synthesis. It is also a source of rumen ammonia.
Metabolizable Energy (ME): This is the energy provided by the feed after energy losses in feces, urine, and gas are subtracted.
Neutral Detergent Fiber (NDF): This is fiber that is insoluble in neutral detergent. It approximates the fibrous components of the cell wall and includes cellulose, hemicellulose and lignin.
Acid Detergent Fiber (ADF): This is fiber that is insoluble in acid detergent. It includes cellulose and lignin. It is lower in digestibility than NDF.
Nonfiber Carbohydrate (Nonfiber CHO): Nonfiber carbohydrate includes carbohydrates such as organic acids, mono- , di- , and oligosaccharides, starch, fructans, pectins, and β-glucans. Organic acids, sugars and starch are digested by mammalian enzymes.
Physically Effective Neutral Detergent Fiber (peNDF): This is the fraction of fiber in the diet that stimulates rumination and increases chewing. Particle size is the primary physical characteristic. Medium and coarsely chopped forages are more effective than finely chopped forages. Feed particles greater than 1 cm in length promote rumination and provide effective NDF.
Total Mixed Ration (TMR): A TMR contains a mix of all dietary feedstuffs. This includes the forages and the concentrate supplement if one is fed. Feeding a TMR provides a uniform feed so each mouthful contains all dietary nutrients.