Whole Soybeans

Cheap Soybeans --- Sell ‘em or Feed ‘em ?

Clifton L . Willms, Ph.D., P.A.S.

Cattle Nutritionist

When grain and soybean prices are low, it makes sense to evaluate the opportunities for feeding raw soybeans. Under most market conditions, it is more advantageous to sell the soybeans, extract the oil, and purchase soybean meal in return. During processing, heating of soybean meal destroys certain anti-nutritional factors, making a more valuable protein that is cost effective.

However, when bean prices are low, freight and processing costs make up a higher percentage of total input costs. The opportunity for eliminating these costs can be realized by cattle producers under the right conditions. Many times the decision is not as simple as a price comparison of nutritional feeding value. The overall feeding program (other feedstuffs, types of rations fed, class of cattle, etc.) and the feed handling system needs to be considered.

This article provides information to help producers determine the feeding value of whole soybeans.

Nutritional profile and nutritional characteristics:

	Whole soybeans are approximately 40% CP (DM basis) and 20% fat. Soybeans are a good source of protein and energy that can be used in cattle and sheep rations.
	Soybeans contain approximately 0.27% calcium and 0.65% phosphorus.
	The protein fraction of soybeans is high quality, but is very rapidly degraded (estimated at 74% degraded) by rumen microbes. To put this in perspective, the following table is provided for reference:

*Ruminal protein degradability of some common feedstuffs.*
Feedstuff:	Degradability (% of protein)
Raw soybeans	74%
Soybean meal	65%
Cotton seed meal	57%
Sunflower meal	74%
Adapted from 2000 Feedstuffs Reference Issue. Vol. 76. No. 29.

	The fat component of the raw soybean does not appear to interfere with ruminal digestion as some have postulated. Supplemental fat added to soybean meal can interfere with digestion, yet in native soybeans, the high fat content does not appear to lower digestion and performance (Davenport et al. 1987)
	Raw soybeans contain trypsin inhibitor. This is a major concern in monogastric animals, but not a factor in ruminants due to the rapid rate of protein degradation. Heating destroys trypsin inhibitor and hence the improved value of feeding SBM after oil extraction in diets designed for monastic animals.
	Raw soybeans contain the enzyme urease. Urease acts to breakdown urea to ammonia. Feeding raw soybeans in combination with a NPN-containing supplement can cause concern about ammonia toxicity, especially in high forage diets with low energy content. However, NPN has been fed with raw soybeans in high grain finishing diets and lactating dairy cow diets successfully without lowering performance (Marston et al., 1997; van Dijk et al., 1983).
	Soybeans do not replace the total need for a supplement. They are only a commodity ingredient. Their use will likely change the nutritional profile of the supplement needed (e.g. calcium, trace minerals, vitamins, NPN levels, etc) depending on other ingredients in the ration. One may still need a means to include a feed additive (e.g. Rumensin, Bovatec, Cattlyst, Gainpro, etc.) as well.

Soybeans for growing diets (high forage):

	Soybeans provide a good source of protein for growing diets.
	Cattle performance on growing rations with raw soybeans is usually slightly below similar rations that use soybean meal, but better than when NPN is the sole source of supplemental protein.
	The rapid rate of protein degradation of whole beans appears to be a key factor limiting performance of cattle fed high forage diets. This stands to reason since the protein in forages tends to be rapidly degraded as well. Therefore, young animals are limited in bypass protein with these types of diets.

*Soybean or SBM supplementation of mature orchardgrass hay*
	No Supplement	Whole soybeans	Extruded soybeans	SBM (32%) + Barley (68%)
ADG, lb./d	.88	2.18	2.42	2.42
Feed/gain	14.65	7.6	6.9	7.0
Albro et al. 1993. JAS 71:26

*Supplementation of corn silage diets with raw, ground soybeans alone or in combination with other sources*
	Ground soybeans	Ground SB + lysine	Ground SB + fish meal	Ground SB + fish + lysine
ADG, lb./d	1.83	1.91	2.22	2.27
Feed/gain	7.39	7.01	6.13	6.06
Davenport et al. 1990. JAS 68:3773

The above two tables are presented to illustrate previous points and provide a better understanding of the nutritional dynamics. However, extrusion or adding uncommon ingredients defeats the purpose of considering whether or not to feed native soybeans. The appeal for feeding raw soybeans when prices are low is the opportunity for eliminating processing and handling costs. Minimal processing is required to make feeding native soybeans cost effective.

Feeding soybeans whole (unprocessed) tends to allow for greater animal performance than grinding or cracking. Feeding the soybeans whole slows the rate of protein degradation in the rumen and allows for improved utilization of the protein fraction. Hence, performance is improved.

SBM vs. Raw Soybeans in Corn Silage Growing Rations
		10% raw soybeans
	SBM	Rolled	Whole
ADG, lb.	2.40	2.07	2.17
DM intake, lb./d	16.0	14.1	14.1
Feed/gain	6.67	6.86	6.51

540 lb. steers; 52 NEg rations, corn levels decreased with increasing soybeans to equalize energy density.
Adapted from Mader, T. 1988. Nebraska Beef Cattle Report.

Soybeans for finishing diets:

Minimal processing, if any, is needed.

Steers fed steam-flaked corn-based rations and supplemented with rolled soybeans tended to have higher ADG than steers supplemented with steam-flaked soybeans at the same level in the final diet (7.5% dry matter). Further, processing was easier and less costly with lightly rolling beans vs. steam flaking. There was clearly no advantage to processing soybeans further than lightly rolling (Marston et al., 1997).

*Replacing SBM and Tallow with Soybeans in* *Steam-Flaked Corn Finishing Diets*
	Urea	SBM	Dry Rolled Soybeans	Steam-Flaked Soybeans
ADG, lb.	3.29	3.26	3.37	3.12
DM Intake, lb./d	19.9	19.6	19.8	18.9
Feed/gain	6.06	5.99	5.89	6.08
Marston, et al. 1997. KSU Cattle Feeders’ Day. Southwest Research & Extension Center. p. 22.

	Steers and heifers supplemented with dry rolled soybeans performed similar to those supplemented with SBM (Marston et al., 1999).
	Feeding raw beans may be beneficial to small to mid-sized feeders without the capabilities of handling fat. To take maximal advantage of whole soybeans, one should formulate the final finishing ration with similar grain and forage levels and hence a higher NEg content.
	Limited data shows indicates that under certain conditions, there is potential for improvement in marbling and quality grade with feeding raw soybeans.
	Limited data exists with other grain sources. It appears that cattle will perform equally well when supplemented with either cottonseed meal or cracked raw soybeans in 66% cracked corn – 34% grass hay diets. (Edwards et al., 1969.)

Establishing a comparative economic value for feeding soybeans:

Two equations (there may be more) have been suggested as a means to determine if the price of native soybeans is low enough to be used in cattle rations.

Illinois:

Whole SB price/cwt. = 0.35 x corn price/cwt. + 0.75 x SBM price/cwt.

Kansas State: (Marston et al. 1999. Cattleman’s Day Report. p. 96.)

Whole SB price/cwt. = 0.80 x SBM price/cwt. + 0.20 x tallow price/cwt.

The above equation assumes 44% SBM and bleachable fancy tallow.

The above equations are useful but only use a partial nutritive value comparison. If the above equations indicate native soybeans are price competitive, one should formulate a total feeding program and look at costs of total mixed rations. Due to the substitution of major ingredients, modifications to the supplement to properly balance a ration, and the feed handling equipment on various operations, the feasibility of raw soybeans may or may not be justified. You can contact a Land O' Lakes, Inc. Beef Specialist to make ration comparisons.

Storage and handling considerations:

Soybeans must be dried to below 13% moisture to prevent bin molding.

Storage molds can be extremely toxic.

Due to the high fat content of soybeans, cracked beans and poor storage conditions can lead to fat rancidity. This lowers the energy content as well as palatability.

For projecting the use of native soybeans for your specific situation and how to best build a nutritional program that optimizes the use of your resources, contact your local Land O' Lakes, Inc. affiliated cooperative and ask a beef consultant to calculate computer projections with your specific input criteria.

	Whole SB price/cwt. = 0.80 x SBM price/cwt. + 0.20 x tallow price/cwt.
	The above equation assumes 44% SBM and bleachable fancy tallow.

	Soybeans must be dried to below 13% moisture to prevent bin molding.
	Storage molds can be extremely toxic.
	Due to the high fat content of soybeans, cracked beans and poor storage conditions can lead to fat rancidity. This lowers the energy content as well as palatability.