Biuret was a hot topic of livestock research in the 60s and 70s and almost 50 research articles have been published about biuret since in 1959. Biuret is a feed ingredient that offers many benefits over the use of traditional urea. But because biuret was kept exclusively within the ruminant product portfolio of Moorman Manufacturing (now ADM) until very recently, the history of biuret was unknown to many. Below is the history of the development of feed-grade biuret. Usage Guide For dark Benefits backgrounds: Biuret attracts little water, Biuret is extremely safe. Biuret’s unique chemis- Biuret has virtually no even in humid conditions, It has been fed at levels try makeup controls the handling restrictions, which allows for ease of 20 times greater than the release of ammonia which which allows for a predict- manufacturing, feed ingre- toxic dose of urea without provides a large margin able process that does dient stability, and good causing death. of safety and contributes not affect the extended to production in various ammonia-release product flowabilty. Logos are © of ADM Alliance Nutrition, Inc., Pantone Color Swatches Typeface/Font uniqueQuincy, conditions. IL 62305-3115 USA characteristics. www.admani.com • 866-666-7626 Berthold Azkizdenz Grostesk Super outlined version: For art questions: call Tracie Hall at 662 187 Black 217-231-2239 or [email protected] History editable version: 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 1958 First patent for manufacture and use in animal feed (Dow Chemical). 1975 Dow Chemical launches first commercial manufacturing. 1976 Approved by the FDA for the use in feeds of non-lactating ruminants. 1982 First successful commercialization of feed-grade biuret by Moorman Manufacturing (now ADM). 2003 Approved by the FDA for use in feeds of lactating dairy cattle. ADM makes buiret avilable for purchase as a stand-alone ingredient. 2010 The Basics… Biuret Urea Feed definition of feed-grade biuret. Biuret is a non-protein nitrogen (NPN) source for ruminants that is defined by the Code of Federal Regulations in CFR 573.220 and in AAFCO as definition 66.2. Figure Urea Vs. Biuret — Urea gained 45% water Composition and physical vs. biuret that gained 9% water, after 48 hours characteristics. 1 in a humidity chamber. Biuret typically contains 253% crude protein (38.5% minimum nitrogen guarantee) with no more than 15% urea. Biuret is composed of small to medium O O O granules and is white to gray in color (see Figure 1). N H2N NH2 H2N H NH2 Biuret is Urea Biuret is chemically and extremely Heat Biuret physically different than urea. safe. (See Figure 2) Biuret is made by heat- O O O Urea must be Chemical polymerizing urea. Chemically, feed- used very carefully H N N N NH grade biuret contains 58% biuret and a in ruminant applica- Composition 2 H H 2 combined 27% of triuret in both straight tions, due to the risk of Triuret and ring forms. In the rumen, these ammonia toxicity and death Figure compounds solubilize and break down because of its extremely rapid to ammonia very slowly. Although there conversion to ammonia (see Figure 3). is a small amount of urea in feed-grade In contrast, biuret has been fed at levels 2 The unique biuret, it is tightly imbedded in the biuret 20 times greater than the toxic dose of chemistry means crystals. urea without causing death. Although that biuret is still con- biuret is classified and regulated as an Biuret does not attract water. NPN source, there are few practical tributing to rumen It is not like urea, which is very hygro- upper limits for its use in dry or liquid ammonia even more scopic and readily attracts water from feed applications. than a day after its air and the feed matrix. As such, special consumption. precautions must be taken in formulation Biuret’s unique chemistry and handling to limit the caking and controls the release of that ration ingredients and other dietary flowability problems caused by urea in ammonia. conditions do not affect the ammonia- almost all classes of feed products. Biuret is not urea and does not require release characteristics of biuret. Biuret’s In contrast, biuret attracts little water, special coatings to achieve controlled ammonia-release pattern (see Figure 3) even in extremely humid conditions release of ammonia into the rumen. Unlike is close to that of vegetable proteins; (see Figure 1). There are very few coated (encapsulated) ureas that are very however, biuret sustains ammonia release ruminant formulations or feed processing fragile, biuret has virtually no handling for many more hours than vegetable conditions under which biuret would be restrictions. By its chemical nature, proteins or coated-ureas. This means expected to cause problems with manu- biuret dissolves slowly and is degraded biuret is still contributing to rumen facturing, feed ingredient stability, by unique rumen enzymes to ammonia. ammonia even more than a day after or product flowability. The predictability of this process means its consumption. Nutritional application of biuret Biuret’s primary value is its highly that beef cows and controlled conversion to ammonia in the stockers consuming rumen. This provides both a large mar- biuret maintained gin of safety relative to ammonia toxicity body condition and contributes to performance under better than controls. conditions in which ammonia availability may limit forage intake or rumen function. Feedlot cattle: Although biuret is Cattle on range and an effective NPN lower-quality pasture: source for feedlot Because ammonia is a critical nutrient rations, it is not cost for fiber-digesting bacteria, insufficient competitive with rumen ammonia dramatically limits fiber urea when directly digestion which reduces both forage included as an energy value and feed intake. Because ingredient in blends of this, crude protein (nitrogen) is typi- of complete feedlot cally the most critical factor limiting the rations. However, performance of cattle consuming either for pre-blended or urea products. There is no scientific winter pastures or low-protein hays or manufactured feedlot minerals, biuret agreement on a “best” ammonia release roughages. Whereas urea or vegetable may help reduce mineral handling prob- pattern for these products and ration proteins provide adequate ammonia lems when substituted for urea. formulation programs generally cannot to the rumen for only a few hours (see model the effects of slow-release NPN Figure 3), biuret is capable of releasing Dairy rations: sources. ammonia into the rumen for greatly Biuret can be included in rations for extended amounts of time. This is lactating cows at 0.1 to 0.2 lb per head Sheep and goats: particularly important when cattle may daily. Best results are attained if urea Biuret is approved for sheep and goats. consume free-choice or hand-fed is also included, typically at a 1:1 ratio In general, sheep and goats fed biuret protein supplements only once a day or with biuret. The formulation strategy for will perform similarly to cattle when on even less frequently. Under these cir- using biuret will be similar to that when low-protein forage. cumstances, extensive research shows using fat-encapsulated, slow-release Formulation guidelines and recommendations There are three primary reasons to use Free-choice beef minerals: some of the bridging problems caused by biuret in ruminant formulas: The hygroscopic nature of urea greatly usage of high levels of urea. Biuret has reduces its usefulness for this application. 1) as a highly safe alternative to urea no impact on the pelleting characteristics Biuret inclusion in this application could of typical protein supplements. 2) as a sustained or slow-release NPN reach up to 30% of the formula. Higher source levels of biuret may become impractical Range cubes: 3) as a non-hygroscopic NPN source. for balancing mineral consumption relative Biuret can be used in cubes or cakes for to animal requirements. its safety and ammonia-release charac- Following are some guidelines and sug- teristics. With up to 25% of the NPN as gestions for using biuret across the most Pelleted protein supplements: urea, range cubes with as much as 40% common ruminant ration and product Biuret can substitute for some urea in crude protein can be safely formulated applications. Table 1 provides a quick high protein pellets. This can help reduce using biuret. reference to these recommendations. Table 1 Suggested guidelines for including biuret in forms of manufactured ruminant feeds. Mineral-protein lick blocks: Forms of Upper limit in formula Co-usage of Depending on target consumption (block manufactured urea with biuret 1 hardness), biuret can be used at up to ruminant feeds Urea Biuret (total NPN) 15% of high-protein blocks. Biuret will Free-choice beef minerals — 30% No urea have little impact on block hardness. 1 Pelleted protein supplements 2-3% 5% up to /3 as urea Tubs (cooked or pressed): Range cubes 3-4% 8% up to ¼ as urea Considering target intake for most tub products, biuret inclusion will rarely need Mineral-protein lick blocks 5-8% 15% up to ½ as urea to exceed 10% of the formula. At the 1 Tubs (cooked or pressed) 3-5% 10% up to /3 as urea highest protein levels, urea can comprise up to one third of the NPN. However, Liquid feed 3-6% 10% up to ¾ as urea during drought or any conditions where Vegetable protein replacers 1-2% 5% up to ¼ as urea forage availability is limited, it is recom- mended that the urea level be reduced in 1 At the maximum level of formulated protein or level of ration inclusion. these higher protein products due to the possible risk of over-consumption. Liquid feeds: Vegetable protein replacers: Generally, biuret can be included in these Up to 5% biuret can be used make “pro- Biuret Guaranteed Analysis applications only when very high protein tein replacers” that are sold as low-cost levels are desired or with very exten- alternatives to soybean meal.