Communities in English
Advertise on Engormix

Amino Acid Content in Organic Soybean Meal for the Formulation of Organic Poultry Feed

Published: February 28, 2019
By: Claudia Dunkley, Justin Fowler, and Samuel E. Aggrey / Department of Poultry Science, University of Georgia.
Over the past several years, organic poultry production has been rapidly expanding (Rogenburg et al., 2008). This alternative to conventionally produced poultry meets consumers’ expectations for healthier animal protein sources (ATTRA, 2010). According to standards set by the U.S. Department of Agriculture (USDA) National Organic Program, to be certified “organic poultry,” birds must be raised with outdoor access, fed certified organic feed, and should not be fed with feed containing antibiotics, animal byproducts, drugs, or synthetic parasiticides (USDA, 2012).
A total of 20 amino acids are the building blocks of proteins and are derived from plant and animal feedstuffs (Reid et al., 2006). Some amino acids, called  “essential amino acids” (EAA), cannot be synthesized by the chicken and must be supplied in the diet (Reid et al., 2006). When the dietary protein has less of an EAA relative to the animal’s requirement for that EAA, it’s referred to as a “limiting amino acid.” Protein synthesis becomes limited by the first limiting amino acid; the limiting EAA will then impair the utilization of all the other amino acids. Methionine (MET) is the first limiting amino acid for poultry when they are fed diets formulated from the most commonly used feed ingredients (Chalova et al., 2015). It is involved in the synthesis of proteins and can be found in many body parts (ATTRA, 2010). As methionine is an EAA that cannot be synthesized by the body, the quantity needed for protein synthesis must be provided in the diet. It is also possible to manufacture MET as a pure amino acid.
Synthetic MET was allowed in organic poultry feed because of its importance in avian physiology and the limited availability of organic protein that is rich in MET (USDA, 2012). There is a limit on the period that synthetic MET can be used in organic poultry feed. Companies in the U.S. that grow organic birds are concerned that fast-growing birds with reduced MET levels will perform poorly and will also have welfare issues such as impaired immune function, which can result in poor feathering, feather pecking, cannibalism, and eventually, mortality (ATTRA, 2010). To avoid the inclusion of synthetic MET in animal feed, high-MET corn varieties that contain up to 50% higher levels of methionine have been developed (Phillips et al., 2008). While it has been shown to be a suitable replacement for conventional corn, the Methionine Task Force (2008) concluded that the lower yields and higher cost of the high-MET corn would deter its widespread use.
Methionine and cysteine (CYS) are referred to as the “sulphur amino acids” (SAA) and they are involved in complex metabolic processes. While CYS is not an essential amino acid because it can be formed from MET, its synthesis is not enough to meet the body’s requirement when a diet is deficient in MET (ATTRA, 2010). While corn does contain a sufficient amount of SAA relative to a chicken’s requirements, it is deficient in the EAA arginine (ARG) and lysine (LYS). Soybean meal has an excess of those amino acids, so the two together make a balanced protein source when blended. However, soybean meal has less SAA than what a chicken requires, and while the ARG and LYS needs are met, a corn-soybean meal blend remains deficient in SAA.
Essential amino acids do not just need to be present in the diet; amino acid availability is an important measure of protein quality. Availability is a measure of how much of what is in the feed the animal is able to digest and absorb. The formulation of diets based on EAA availability can help to decrease feed cost and reduce excess nutrients being excreted into the environment. Determining the availability of amino acids in organic ingredients is critical for formulating suitable organic poultry diets. A study was conducted where a number of organic feed ingredients were evaluated and compared to nonorganic feed ingredients for the formulation of organic feeds for organic poultry production. Table 1 provides a comparison of EAA in conventional soybean meal (CSBM) with those in organic soybean meal (OSBM).
Soybeans are used as the predominant source of amino acids in poultry diets (Gandhi et al., 2008). Soybean meal has a high protein content as well as highly digestible amino acids which make it a useful supplement in monogastric diets (Meng and Slominski, 2005; Gandi et al., 2008). The amino acid in an ingredient is expressed as its average percentage in the total ingredient, and the digestibility is expressed as the percentage of the total amount that is available through digestion.
Organic SBM has higher total amounts of CYS and MET and higher digestibility for CYS. This can help compensate for the inability to use synthetic MET in the diet.
The crude protein and individual amino acid content of organic soybean meal compare favorably with that of conventionally grown soybean meal (Table 1). The digestibility of the essential amino acids in the OSM is high and compares favorably with the conventional soybean meal. As seen in conventional poultry diets, organic poultry diets should be formulated with organically grown soybean meal, as the digestibility of the amino acids in organic soybean meal is similar or higher than in conventional poultry diets.
Amino Acid Content in Organic Soybean Meal for the Formulation of Organic Poultry Feed - Image 1
This research was sponsored by USDA Organic Transition Award 2014-51106-22093.
This article was originally published in Circular 1140, June 2018, University of Georgia Extension.
Chalova, V.I, Kim, J., Patterson, P.H., Ricke, S.C., & Kim, W.K. (2016). Reduction of nitrogen excretion and emission in poultry: A review for organic poultry. J. Environ. Sci. and Health. Vol: 51, No. 4. 230-235.
Chalova, V.I., Sirsat, S.A., O’Bryan, C.A., Crandall, P.G., & Ricke, S.C. (2009). Escherichia coli, an intestinal coli-based biosensor for quantification of amino acid bioavailability. Sensors 9:7038-7057
Fanatico, A. (2010). Organic Poultry Production: Providing adequate methionine: National Sustainable Agriculture Information Service: Butte, MT. 20.
Gandhi, A.P., Jha, K., & Gupta, V. (2008). Studies on the production of defatted sunflower meal with low polyphenol and phytate contents and its nutritional profile. ASEAN Food J. 15:174-183.
Groff, J.L., & Gropper, S.S. (2000). Protein. In: J.L. Groff and S.S. Gropper (eds) Advanced Nutrition and human metabolism. 3rd edn. Wadsworth Publishing, Florence, KY. 162-219.
Jacob, J.P., Levendoski, N., & Goldstein, W. (2008). Inclusion of high methionine corn in pullet diets. J. Appl. Poult. Res. 17:440-445.
Meng, X., & Slominski, B.A. (2005). Nutritive values of corn, soybean meal, canola meal, and peas for broiler chickens as affected by a multi carbohydrase preparation of cell wall-degrading enzymes. Poult. Sci. 84:1242-1251
Methionine Task Force (2008). Transcripts of May 21 2009, National Organic Standards Board Meeting, Baltimore, MD. Retrieved from http//www.ams.usda.gov
Nelson, D.L., & Cox, M.M. (2005). Lehninger Principles of Biochemistry, 4th ed. W.H. Freeman and Company, New York, NY.
Phillips, R.L., Suresh, J., Olsen, M., & Krone, T. (2008). Registration of high methionine version of maize inbreds A632, B73, and Mo17. J. Plant Reg. 2:243-245.
Razani, B., Woodman, S.E., & Lisanti, M.P. (2002). Caveolae: from cell biology to animal physiology. Pharmacol. Rev. 54:431-467.
Reid. W.M., Pesti, G., Hargis, B., Moore, R., Vohra, P, Dean, W., & Hammarlund, M. (2006). Raising healthy chickens. 4th ed. Christian Veterinary Mission, Seattle, WA. 38-42.
Rogenburg, T.B., Van Harn, J., van Krimpen, M.M., Ruis, M.A.W., Vermeij, I., & Spoolder, H.A.M. (2008). Comparison of three different diets for organic broiler: effects on performance and body condition. Brit. Poult. Sci. 49: 74-80.
USDA (2012). 7 CFR Part 205. National Organic Program (NOP); Amendment to the National List of Allowed and Prohibited Substances (Livestock). Federal Register 2012. 77(182), 57985-57990.
Related topics
Dr. Claudia Dunkley
University of Georgia
Justin Fowler
University of Georgia
Join to be able to comment.
Once you join Engormix, you will be able to participate in all content and forums.
* Required information
Would you like to discuss another topic? Create a new post to engage with experts in the community.
Create a post
Antônio Mário Penz Junior
19 de marzo de 2019
I fully agree with Dr. Waldroup's consideration. Let's avoid confusion where it is not there.
Park W. Waldroup
University of Arkansas (USA)
17 de marzo de 2019

As Martin Smith pointed out, digestibility of soybean meal is more a function of processing due to variance in the heating used for solvent removal. Unless the comparison is made between beans of the same variety grown in the same geographical region under similar soil types and processed under the same conditions, any comparison of conventional and organic soybeans is invalid. I wish some people had taken a course in experimental design, we would not have so much invalid information running around.

Park W. Waldroup
University of Arkansas (USA)
17 de marzo de 2019

There is a difference in crude protein levels of soybeans grown in different latitude in the US as different varieties have been developed by agrinomists for particular regions. I have not seen the particular data regarding conventional vs organic but unless you are comparing beans grown in same geographical area...and beans of the same genetic stock...you are already in error

Martin Smith
Evonik Animal Nutrition
17 de marzo de 2019
First, may I politely ask you to give credit to Evonik and properly reference the fact that the "conventional" soya data you quote comes from our AminoDat 5.0 raw material database. Your amino acid values are IDENTICAL to those quoted in this data base and so reference should be noted. You give no data in your paper regarding number of samples in your survey. The AminoDat values are based on 1241 samples collected globally. Please provide some data on sample size and variance so we might able to correctly assess is any difference is actually significant. Certainly growing conditions can influence amino acid content (by altering protein composition) but just comparing means is not sufficient. Regarding digestibility; this has much more to do with processing and NSP content, and again we would need more data to conclude the data provided is actually correct.
Park W. Waldroup
University of Arkansas (USA)
16 de marzo de 2019

is there any evidence that would suggest a difference in amino acid content? If it exists, I would certainly look at sample size.

Marco Aurelio Arredondo
Agranco Corp
19 de marzo de 2019
Dear Dr. Dunkley Not sure if Mortality Compost would have in impact on AA content, still, based on the feedback from this forum, we will run trials with the same beans grown in same geographical area (South east Mexico) on top soil resulting from CAFO´S Organic Matter Compost and then test the AA content and digestibility. We will gladly share the results. We have developed new Fields either for Organic or Conventional Agriculture with good results, so we are confident about the project. If possible, I would like to contact the University of Georgia Poultry Extension, my email is marco@slkta.com. Thanks.
Alfredo Navarro de Andrade
17 de marzo de 2019

I agree that protein content of soybeans may vary depending on variety, fertilization level, degree of maturation of the grain and some other environmental conditions. However, the proportion of the different amino-acids in the protein will not be different between the conventional and organic organic. The only way the same variety of soybean grown conventionally or under the "so called" organic conditions is if there is a change in the DNA structure of the protein of the variety. Science proves that it is true.

Marco Aurelio Arredondo
Agranco Corp
15 de marzo de 2019
Dear Claudia and Justin We are a Company in Austin that pursues similar goals on this Article. Currently we are developing protocols for mortality and litter disposal to use as compost to build top soil on nutrients depleted agriculture fields in Southeast Mexico. The goal is to use those fields to grow organic soybeans. Any input and recommendation from you all will be more than welcome. Great research, congrats.
Join Engormix and be part of the largest agribusiness social network in the world.