Page 40

7—
Composition of Feeds

Tables 13 and 14 present the composition of certain sheep feeds and the composition of mineral supplements, respectively. In both tables, data are expressed on an asfed and dry basis.

International Nomenclature

In Tables 13 and 14 and in the United States-Canadian Tables of Feed Composition (NRC, 1982), which lists approximately 400 feeds, names of the feeds are based on a scheme proposed by Harris et al. (1980, 1981). The names are designed to give a qualitative description of each product where such information is available and pertinent. A complete name consists of as many as six facets, separated by commas and written in linear form. The facets are

1.

Origin, consisting of scientific name (genus, species, variety) and common name (generic name, breed or kind, strain or chemical formula)

2.

Part fed to animals as affected by process(es)

3.

Process(es) and treatment(s) to which the part has been subjected

4.

Stage of maturity or development of feed

5.

Cutting (applicable to forages)

6.

Grade (official grades with guarantees)

International Feed Classes

Feeds are grouped into eight classes:

1.

Dry forages and roughages

2.

Pasture, range plants, and forages fed fresh

3.

Silages

4.

Energy feeds

5.

Protein supplements

6.

Mineral supplements

7.

Vitamin supplements

8.

Additives

Feeds with more than 18 percent crude fiber or 35 percent cell wall (DM basis) are classified as forages or roughages; feeds with less than 20 percent protein and less than 18 percent crude fiber or less than 35 percent cell wall are classified as energy feeds; and those with 20 percent or more protein are considered protein supplements.

The feed class number precedes the international feed number in Tables 13 and 14.

International Feed Number

Each international feed name is assigned a 5-digit international feed number (IFN) for identification and computer manipulation. The IFN is particularly useful as a to recall nutrient data for calculation of diets (Harris, 1963; Harris et al., 1968).

The following table shows how three feeds are described.

Descriptions of Three Feeds, Including Classification and IFN

Components of Name

Feed No. 1

Feed No. 2

Feed No. 3

Origin (or parent material)

Clover

Cotton

Wheat

Species, variety or kind

Red

Part eaten

Hay (foliage)

Seeds

Flour by-product

Process(es) and treatment(s) to which product has been subjected

Sun-cured

Meal mechanical extraced

Stage of maturitya

Early bloom

(table continued on next page)



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Page 40 7— Composition of Feeds Tables 13 and 14 present the composition of certain sheep feeds and the composition of mineral supplements, respectively. In both tables, data are expressed on an asfed and dry basis. International Nomenclature In Tables 13 and 14 and in the United States-Canadian Tables of Feed Composition (NRC, 1982), which lists approximately 400 feeds, names of the feeds are based on a scheme proposed by Harris et al. (1980, 1981). The names are designed to give a qualitative description of each product where such information is available and pertinent. A complete name consists of as many as six facets, separated by commas and written in linear form. The facets are 1. Origin, consisting of scientific name (genus, species, variety) and common name (generic name, breed or kind, strain or chemical formula) 2. Part fed to animals as affected by process(es) 3. Process(es) and treatment(s) to which the part has been subjected 4. Stage of maturity or development of feed 5. Cutting (applicable to forages) 6. Grade (official grades with guarantees) International Feed Classes Feeds are grouped into eight classes: 1. Dry forages and roughages 2. Pasture, range plants, and forages fed fresh 3. Silages 4. Energy feeds 5. Protein supplements 6. Mineral supplements 7. Vitamin supplements 8. Additives Feeds with more than 18 percent crude fiber or 35 percent cell wall (DM basis) are classified as forages or roughages; feeds with less than 20 percent protein and less than 18 percent crude fiber or less than 35 percent cell wall are classified as energy feeds; and those with 20 percent or more protein are considered protein supplements. The feed class number precedes the international feed number in Tables 13 and 14. International Feed Number Each international feed name is assigned a 5-digit international feed number (IFN) for identification and computer manipulation. The IFN is particularly useful as a to recall nutrient data for calculation of diets (Harris, 1963; Harris et al., 1968). The following table shows how three feeds are described. Descriptions of Three Feeds, Including Classification and IFN Components of Name Feed No. 1 Feed No. 2 Feed No. 3 Origin (or parent material) Clover Cotton Wheat Species, variety or kind Red – – Part eaten Hay (foliage) Seeds Flour by-product Process(es) and treatment(s) to which product has been subjected Sun-cured Meal mechanical extraced – Stage of maturitya Early bloom – – (table continued on next page)

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Page 41 Descriptions of Three Feeds, Including Classification and IFN—Continued Components of Name Feed No. 1 Feed No. 2 Feed No. 3 Grade or quality designation – 41% Protein ‹ 4% Fiber (wheat) (red dog) Classification (first digit in IFN) Dry Forages and roughages Protein supplements Energy feeds IFN 1-01-400 5-01-617 4-05-203 aSee Table 15 for definitions of stages of maturity. Thus, the names of the three feeds are written as follows: Feed No. 1: Clover, red, hay, sun-cured, early bloom. Feed No. 2: Cotton, seeds, meal mechanical extracted, 41 percent protein. Feed No. 3: Wheat, flour by-product, less than 4 percent fiber (wheat, red dog). Data The analytical data in Tables 13 and 14 are expressed in the metric system and are shown on an as-fed and dry basis. See Tables 16 and 17 for weight unit conversion factors and weight equivalents, respectively. Analytical data may differ in the various NRC reports because the data are updated for each report. The feed names may also differ as feeds are more precisely described or as official definitions change. If the feed is the same, however, the International Feed Number will remain the same. Energy Values Of Feeds Total digestible nutrients. Total digestible nutrients (TDN) were calculated from (1) Average TDN or (2) From digestion coefficients such as   digestible protein (%) × 1   digestible crude fiber (%) × 1   digestible nitrogen free extract (%) × 1   digestible ether extract (%) × 2.25   TDN (%) Total or (3) From regression equations of Harris et al. (1972).   Digestible energy. Digestible energy was calculated with the formula of Crampton et al. (1957) and Swift (1957):       Metabolizable energy. ME was calculated from DE by the following formula:       Digestible protein. Digestible protein was calculated as follows: (1),    (2) By equations of Knight and Harris (1966).

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