Biuret: A Safe, Practical Alternative to Urea

Biuret: A Safe, Practical Alternative to Urea

Feed grade biuret, is an ADM Alliance Nutrition exclusive. It is a mixture of compounds including biuret and small amounts of triuret, cyanuric acid, and urea, and is formed by the controlled decomposition and subsequent processing of urea. Feed grade biuret contains no less than 35% nitrogen and typically has a crude protein value of 246%. Due to its physical and chemical properties, feed grade biuret is more slowly degraded in the rumen compared to urea (Figure 1).

The slower release of ammonia from biuret makes it a safe source of nitrogen for cattle and sheep grazing forages and for cattle fed in confinement. Biuret is at least 7.3 times less toxic than urea. Up to 15 g/lb of body weight of biuret supplementation have not produced toxic effects, while much lower levels of urea supplementation have resulted in death (Table 1). Another advantage of biuret is that it is less hydroscopic (attracts less water) compared to urea. Pellets containing biuret are less likely to cake and bridge compared to pellets containing high amounts of urea.

Range Feeding

Biuret's slow-release of nitrogen provides a safe and sustained supply of ammonia that is well suited for microbial digestion of lower quality forages. In-vitro worked conducted by ADM Alliance Nutrition research showed biuret improved cellulose digestion from 36.7% for the controls (no supplemental nitrogen) to 53.78% for biuret. These observations are supported by Loest and co-workers (Kansas State University) who evaluated the effects of non-protein nitrogen on the intake and digestion of steers fed prairie hay. Steers fed a cooked molasses block containing 60% crude protein (83% from urea or 42% from urea and 42% from biuret) had a 22% increase in forage intake and a 52% increase in digestible organic matter intake compared to non-supplemented cattle. These improvements in forage digestion and intake will result in improved cattle performance.

In a 105-day winter feeding trial, researchers at Montana State University (1996) compared cooked molasses blocks containing 18% crude protein versus blocks containing 42% crude protein with the additional crude protein supplied by biuret. Cows receiving the 18% cooked molasses blocks lost an average 62 lb/hd and body condition score (BCS) decreased by 1/2 point. Cows receiving the biuret supplement maintained body weight and BCS.

A North Dakota field trial conducted by ADM Alliance Nutrition confirms the results observed at Montana. Cows grazing fall range and supplemented with Roughage Buster® over a 40-day period maintained body weight (net gain of 0.95 lb) and had calves which were 18.7 lb/hd heavier than cows which were fed only a supplement containing trace mineralized salt. Cows receiving trace mineralized salt lost an average 27 lb/hd during the trial.

ADM Alliance Nutrition's Field Research conducted six trials evaluating performance of growing cattle supplemented with biuret via Roughage Buster products (Table 2). Roughage Buster supplementation increased ADG 0.40 lb, resulting in a $14.96 increase in net return for Roughage Buster supplemented cattle compared to cattle supplemented with competitive products.

Feedlot Feeding

Biuret's physical properties enable it to be utilized in situations where a NPN "safety" factor is desired in the feedlot. Ammonia toxicity most often occurs when hungry cattle are fed high urea supplements for the first time. Mixing and weighing errors when using high urea supplements can also increase the likelihood of urea toxicity. Work conducted at the University of Minnesota on feedlot finishing diets indicated that biuret supported gains equal to urea supplemented cattle. A study at ADM Alliance Nutrition facilities confirmed these studies - cattle supplemented with biuret gained 3.15 lb/hd/day compared to urea supplemented cattle that gained 3.09 lb/hd/day.

Conclusion

Biuret's physical properties enable it to be utilized in situations where grazing cattle are fed
low-quality, low-energy forages or in feedlot situations where a NPN "safety" factor is desired. The slow-release of nitrogen from biuret is better matched to the energy in the diets of cattle consuming low-quality forages, thus improving the utilization of forage and reducing the metabolic cost of eliminating excess nitrogen in urea-based diets.