LIVESTOCK NUTRITION/FEED ANALYSIS
SAMPLE REPORT WITH REFERENCE GUIDE EXPLANATIONS
Link to -"Proper Sampling Methods" to ensure best results from soil analysis



TOP SECTION:
MOISTURE:
The moisture content of a feed sample is reported as the % of loss in weight of a sample as a result of oven-drying to a constant weight at a temperature just above 100C. All values are reported on a dry basis on the top line, and an "as is" basis on the line below.
CRUDE PROTEIN:
This is usually obtained by multiplying total N by 6.25. Crude protein will include both true protein and non protein N. Animals can utilize both types to some degree. Because forages that are higher in protein are correspondingly lower in crude fiber, higher protein content almost always indicates a higher TDN (Total Digestible Nutrients) figure.
DIGESTIBLE PROTEIN:

This is the portion absorbed by the animal. Digestibility is variable and affects how well a feed will be utilized. Digestible protein may be estimated from standard literature or calculated from ADF insoluble protein.

ADF INSOLUBLE PROTEIN:
The protein content of ADF is often used as an indicator of "unavailable" protein. The crude protein analysis measures only the total protein and tends to overvalue the protein in feeds that have been damaged by heating. Heat damage most frequently occurs in the ensiling process or the drying of grains.
CRUDE FAT:
Crude fat is the amount of fat or oil content of a feed which is extracted by ether. This ether extract contains not only true fat but fat soluble vitamins A, D, E, K, free fatty acids, cholesterol, chlorophyll, lecithin, resins, and volatile oils. In cereal grains most of the ether extract is true fat, but in forage crops more than 1/2 may consist of other compounds. This is one of the major factors causing differences in the gross energy of various feeds, because fat will yield over 9 K cal/g while proteins & carbohydrates yield about 5 K cal/g.
CRUDE FIBER:
This fraction contains the cellulose and other carbohydrates which are insoluble and cannot be dissolved by weak acid or alkali solutions. This is important because feeds high in fiber are less digestible than feeds low in fiber. Forage crops that have higher fiber have lower TDN and energy. Grains which have low fiber have higher TDN and energy.
ADF (ACID DETERGENT FIBER):

The fraction which is not soluble in acid detergent solution. This contains cellulose, lignin, cutin, as well as heat damaged protein. It is more related to digestibility than crude fiber.

ASH:
The ash content of a feed is the percentage of mineral matter. It is the inorganic residue left after firing a sample at 600 degrees C in a muffle furnace for a specified length until the sample is free of carbon. The nutritional significance will depend upon the feed used.
TDN (TOTAL DIGESTIBLE NUTRIENTS):
The sum of the digestible portions of protein, fat, fiber and nitrogen free extract. It represents the approximate energy value of the feed. In recent years, there is a trend away from TDN for expressing the useful energy of feeds and the energy needs of livestock. Net Energy (NE) is now being used more for this purpose.
NITRATES:
Crops grown on soils with balanced soil fertility should not contain enough nitrate to affect metabolism or animal health. However, excess soil nitrogen from unbalanced fertilization or from weather conditions may cause nitrate concentrations at potentially harmful levels for livestock feeding.
CENTER SECTION:
MINERAL ELEMENT CONTENT:
Essential mineral nutrients are those required to complete the animal's life cycle. The level of these mineral elements may be extremely variable in feedstuffs. The type of feed, soil fertility levels, environmental conditions, and many other factors can influence the mineral content. At low concentrations, deficiencies may occur. At excessively high concentrations, mineral nutrients can have toxic effects.
BOTTOM SECTION:
NET ENERGY:

NE is a calculated estimate of the net energy available to the animals consuming the feed. Very simply, NE is the gross energy of a feed minus energy left in feces, energy lost in urine and gas, and energy used in work in digestion and heat increment. The energy that remains is called net energy, and can be used for maintenance, gain, milk production, pregnancy, work, and so on. Energies are most often expressed in caloric units such as Mcal/lb.