10 Concentrates for Beef Cattle 1995 Beef Cattle Feeding and Nutrition Second Edition
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10 Concentrates for Beef Cattle 1995 Beef Cattle Feeding and Nutrition Second Edition

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10

Concentrates for Beef Cattle

Michael J. Cecava

Cattle have the capacity to utilize tremendous quantities of roughage because
of the anaerobic microorganisms found in the rumen. Cattle subsisted primarily
on forages and roughages as sources of energy and other nutrients for centuries.
However, man domesticated cattle and introduced concentrated energy and pro-
tein feedstuffs into the ruminant diet. Concentrate feeding was and continues to
be attractive from an economic standpoint. Cereal grains and animal and plant
proteins can often be used to supply energy and protein at lower cost per nutrient
input compared with forages.

The major source of energy concentrates for cattle is cereal grains, primarily
corn, grain sorghum, barley, oats, and wheat. The major sources of plant protein
concentrates include the oil meals, primarily soybean meal, cottonseed meal, and
linseed meal, and by-products of cereal grain processing, such as corn gluten
meal, corn gluten feed, distiller's grains, and brewer's grains. The major sources
of animal protein concentrates are by-products of the animal processing industry.
These include bloodmeal, meat and bone meal, fishmeal, and poultry feather-
meal.

Lipids also represent a source of energy used in beef cattle diets. The render-
ing industry is a source of tallow and lard (grease) commonly fed to growing and
finishing cattle. Substantial amounts of lipid from vegetable sources, such as
soybean oil, also are used.

Another source of concentrate for beef cattle is molasses. Molasses is a by-
product of the sugar industry and the wood processing industry. Beyond the
nutritive value of molasses, feed manufacturers and cattle feeders often use
molasses to improve the handling and acceptability of manufactured feeds and
diets.

This chapter will discuss the use of concentrate feeds as sources of energy and
protein in beef cattle feeding programs. Discussion will focus on the characteris-
tics of the major concentrates and protein feedstuffs typically fed to ruminants.
For specific information regarding diet formulation, the reader is encouraged to
consult later chapters.

Beef Cattle Feeding and Nutrition,
Second Edition 13B

Copyright �9 1995 by Academic Press, Inc.
All rights of reproduction in any form reserved.

I. The Cereal Grains 139

I. THE CEREAL GRAINS

Quantitatively, corn grain is the most important cereal concentrate fed to
livestock in the United States (Table 10.1). In 1992-93 about 72% of the corn
produced in the United States was used domestically and about 70% of this
amount was used in livestock feeding (Anonymous, 1994). Beef cattle account
for a substantial portion of the grain consumed in the United States (Fig. 10.1).
As would be expected, the majority of grain consumption by beef cattle occurs in
the feedlot. Almost 90% of all cattle on feed are located in 13 states found
primarily in the midwest or high plains regions of the country, where grain is
plentiful (Anonymous, 1994).

All of the cereal grains are high in starch and low in fiber. They are rich in
energy and generally quite palatable. The highest concentrations of digestible
energy are found in corn, grain sorghum, and wheat. Lower energy concentra-
tions are found in barley and oats. Generally, the balance of amino acids is poor
for the cereal grains. Notably, grains tend to be deficient in lysine and tryp-
tophan. Corn is especially low in total protein, averaging 7.8 to 9.0% protein on
a dry matter basis whereas barley and grain sorghum (Fig. 10.2) may contain
12% protein or greater. Cereal grains are extremely low in calcium but almost
adequate in phosphorus relative to the needs of growing cattle.

None of the grains contain vitamin D and only yellow corn contains 13-carote-
ne, the precursor of vitamin A. However, research has shown that the conversion
of carotene to vitamin A by finishing beef cattle is quite low. Consequently, diets
containing high levels of corn grain must be supplemented with vitamin A.

TABLE 10.1

Concentrate Feed Consumption (in Millions of Metric Tons)
in the United States o

1991 1992 1993

Annually
Corn 124.4 134.6 123.2
Grain sorghum 9.4 12.1 11.7
Oats 3.3 3.0 2.7
Barley 5.1 4.1 5.0
Wheat and rye 2.0 4.2 11.0
Oilseed meals 23.5 24.4 24.7
Animal protein feeds 3.0 2.9 2.9
Grain protein feeds 2.7 0.8 0.8
Other by-product feeds 11.6 12.5 12.5
Total 185.0 198.6 194.5

aAdaptod from Anonymous (1994).

140 10. Concentrates for Beef Cattle

Other
1% Dairy Cattle

Hogs ~ 1 2 %

Cattle on
Feed

28%

Poultry
29%

Other Cattle 5%

Fig. 10.1 Grain consumption by livestock species in the United States. Adapted from Anonymous
(1994).

A. Corn

The hull and the germ are the more well-defined entities of the corn kernel
(Fig. 10.3). Just under the hull is a shallow layer, predominantly composed of
gluten, which contains most of the protein. Toward the center of the kernel is a
mixture of gluten and starch. The corn kernel contains 55% starch, 16% water,
and 29% gluten, hull, and germ. Corn oil amounts to about 3% of the kernel
weight.

Corn is rich in nitrogen-free extract, nearly all of which is starch. It has the
highest concentration of ether extract of all cereal grains except for oats. It is low
in fiber and is highly digestible. Corn is the most palatable of all grains for beef
cattle and more cattle are finished on corn than on all of the rest of the cereal
grains combined.

The yellow color of corn is partly attributable to the carotenes found in the
kernel. The characteristic yellow is also attributable to xanthophyll, which is a
critical compound for imparting the desirable yellow color to the subcutaneous
adipose of chickens.

There is no nutritional justification for grinding air-dry corn for beef cattle,
but most nutritionists and cattle feeders recommend at least rolling of ensiled
high moisture corn. Almost any kind of heat processing or ensiling of high-

I. The Cereal Grains 141

Fig. 10.2 Milo, properly processed, is a most excellent cattle feed. (Photo courtesy of BEEF
Magazine.)

142 10. Concentrates for Beef Cattle

Fig. 10.3 Corn is the No. 1 grain fed to livestock in the United States. (Photo courtesy of BEEF
Magazine.)

moisture (25% moisture) corn will improve its nutritive value by about 10%. The
reason for this is not clear but cattle feeders should consider roasting, steam
flaking, micronizing, or moisturizing corn to increase the digestible energy con-
tent.

The stage of maturity at which corn is harvested affects the total nutritive
value of the kernel. Note from Table 10.2 that the starch and nitrogen-free extract
(NFE) do not approach their maximum concentration until the corn grain is at
least at the mid-dent stage. Therefore, unless an early frost, drought, or blight
dictates a relatively early harvest, it is best to allow corn to mature for optimum
digestible energy content. Because protein deposition occurs early in the matura-
tion process, the protein content of the corn kernel actually decreases with
advancing maturity and deposition of starch. Therefore, early harvested corn
may have a slightly higher protein content than mature corn.

The by-products of corn grain processing can be utilized as feedstuffs in beef
cattle diets. These include corn gluten meal, corn gluten feed, corn germ meal,
corn steep liquor, and distiller's dried grains. When competitively priced, by-
products can be used to partially replace traditional feedstuffs. The use of by-
products will be discussed in the section dealing with miscellaneous concentrate
feeds.

I. The Cereal Grains 143

TABLE 10.2

Effect of Maturity on the Chemical Composition of Corn Grain ~
i

Early milk Early dough Mid-dent Mature

Concentration