Feed costs represent the greatest proportion of a beef cattle enterprise.
Producers must strive to efficiently utilize available resources while
optimizing animal performance and minimizing cost. When cattle graze marginal to
low quality forages, supplemental protein and/or energy is required to enhance
either the utilization of forage or animal performance. By-products have an
opportunity to reduce the cost of supplementation while maintaining or improving
animal performance. The following co-products have been effective as feed
ingredients in a number of situations. These by-products have been developed as
a result of processing a traditional feed ingredient to generate another
Corn gluten feed- is a by-product of corn wet milling which produces high
fructose corn syrup. A kernel of corn has 5 primary constituents: starch,
gluten, hull, water, and germ. Corn gluten feed is that portion of the corn
kernel that remains after extraction of starch, gluten and germ. The major
constituent in CGF is the hull or bran, along with the gluten, protein.
Dried distillers grains- Dried distillers grains (DDG) are by-products of the
distilling industry, in which grains are fermented into alcohol. The spend
grains are dried and sold as feedstuffs primarily used in ruminant diets.
Solubles remaining from fermentation usually are added to the grains before
drying resulting in a product called distillers dried grains with solubles.
Distillers' grains are identified from the type of grain from which they are
made (corn distillers, milo distillers etc.) distillers' grains contain 25 to
30 5 CP and 10 to 12 % fat.
Soybean hulls-soyhulls are generated from the rolled or cracking of soybeans
into small pieces so that hulls can be removed. Soyhulls are separated from the
cracked seeds by an air stream, and seeds are extracted with hexane to remove
oil, leaving high protein bean meal (48 %). Next, the soyhulls pass through a
toaster to destroy the unease activity. Finally, the hulls are ground to the
desired particle size and stored to be added back to the $ bean meal or shipped
as soyhulls. Soyhulls contain approximately 12 to 14 % CP. They are an excellent
energy source in the form of digestible fiber.
Wheat Midds-Approximately 25 % of total wheat milled is left as a byproduct,
and termed wheat middlings or mill feed. This by-product feed has been used in
ruminant diets and is widely used in commercial supplements as a protein and
energy source. Wheat midds tends to vary in nutrient composition due to the
varying amount of flour starch. The CP content of wheat midds is 15 to 19 % and
energy is in the form of fiber and starch.
By-products are being used as energy and protein supplements for growing
cattle as well as cows. In these situations, supplemented to moderate to low
quality forage or where forage availability is limiting.
Excellent energy and protein source
Less risk of digestive upset due to over consumption
Need to look at mineral differences
Storage and handling can be a
problem. Producer must take these in bulk form, semi-trailer delivery, and must
have storage and handling facilities.
Thiamin deficiency in the rumen with
wet corn gluten feed due to high sulfur content.
nutrient composition of these by-products (% of DM)
The composition of the by-products suggests that the protein is more
degradable than corn, while the NDF in these by-products is also higher than
corn. The DDG is the best source of fat. One must take the nutrients into
consideration when balancing a diet with these co-products.
Performance of steers receiving
fescue hay supplemented with corn, SH, or wheat midds
Hay DM intake (%BW)
Sup. DM intake (% BW)
Feed cost/lb gain
Crawford and Garner, 1993, J.An.Sci. 71 suppl.1, p. 185
Fescue hay valued at $45 per ton, corn, SH and WM valued at $80 per ton
The use of the by-products as a source of energy for steers fed fescue hay
revealed that they are better than corn as replacement for energy. One must keep
in mind that SH and WM also have more degradable CP than corn. In terms of cost
per unit of gain, all three supplements have better cost of gains than no
supplement but the by-products are also cheaper than corn.
The addition of by-product feeds, like soyhulls or corn gluten feed, have
advantages as a supplement to high roughage, low energy diets as compared to
using corn grain. When comparing Wet and Dry corn gluten feed for beef cattle in
grass hay, the supplement did not depress hay intake or reduce fiber
digestibility. The protein quality of corn gluten feed has been compared to
soybean meal and found that it is almost equivalent to soybean meal as a protein
source for growing cattle. Wet corn gluten feed was superior to dry corn gluten
feed in a corn silage based diet. Wet corn gluten feed was superior to dry corn
gluten feed when diets contained less than 70 % corn silage. Digestibility of DM
and NDF are 5-10 percent higher in diets containing wet corn gluten feed as
compared to dry corn gluten feed. Explanation may be: Particle size differences;
effect of particle size on fiber digestion in the rumen; Particle size of wet
corn gluten feed is larger than dry corn gluten feed. Generally particles
smaller than about 1 mm are not retained in the rumen.
Level of corn silage
Low silage diet
95% of C
86% of C
Medium silage diet
95% of C
92% of C
High silage diet
102% of C
102% of C
As corn silage in diet increases, the energy value of CGF relative to corn
increases. This may be attributed to the negative associative effects of corn on
A similar relationship has been established for brome hay diets with
supplemental soyhulls and corn. Addition of soyhulls improved ruminal and total
tract digestibility. The addition of .21 % BW corn with .42 % BW SH further
increased ruminal digestibility. Feeding .63 % BW corn decreased ruminal
Substituting corn at .2 % BW for soybean hull for energy had no negative
effects on forage utilization. Thus the inclusion of soyhulls at low inclusion
rates in high forage diet (> 50 % forage) for beef cattle resulted in similar
energy value to that of corn.
The inclusion of soyhulls in high concentrate diets resulted in a feeding
value of 74 to 80 of that of corn. The use of soyhulls at a level of > 20 5
diet dry matter in concentrate based diets will be dictated by the cost of
soyhulls relative to cereal grains. The criteria utilized to evaluate the
relative feed value will be gain, intake, and feed efficiency.
Distillers' grains in diets for beef cattle are a good source of protein,
energy, and phosphorus. They have the potential for meeting a major portion of
beef cattle requirements for these nutrients. They contain, however, less than
the required amounts of calcium and potassium. Based on considerable research
studies, wet distillers' corn grains alone or in combination with urea are
equal in value to soybean meal or corn gluten meal in supplying total
supplemental protein requirements for growing and finishing beef cattle. The
only exception to this relationship was the results for sorghum stillage in
which it was inferior to soybean meal. In summary of several studies, the
addition of 50 % wet distillers' grains in a finishing for 680 lb steers
resulted in 10 % improvement in gain and feed efficiency of steers as compared
to those fed a corn diet. These studies suggested that wet distillers' grains
could replace half of the corn or milo in finishing diets.