DECISION SUPPORT MODEL OF NUTRIENT EXCRETION IN BEEF FEEDLOTS

Authors: Williams, Charles; Jenkins, Thomas

Submitted to: American Society of Animal Science Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 2/13/2006
Publication Date: 7/11/2006
Citation: Williams, C.B., Jenkins, T.G. 2006. Decision support model of nutrient excretion in beef feedlots [abstract]. Journal of Animal Science 84(Suppl. 1):291.

Interpretive Summary:

Technical Abstract: Component biological models were developed at the U.S. Meat Animal Research Center to partition ME and protein intake to maintenance and gain, and partition protein and ME for gain to fat and protein accretion in growing and mature cattle. These models were integrated with a life cycle beef production model developed at Colorado State University, and phosphorus and potassium intake and utilization were added. Evaluations with independent sets of experimental data showed that the beef life cycle model could accurately predict responses under different levels of nutritional management. This integrated model represents a nutrient utilization model of nitrogen, phosphorus, and potassium, and it was integrated with the nutrient supply model of the Cornell Net Carbohydrate Protein System to predict nutrient supply. Nutrient excretion was predicted as the difference between supply and utilization. Use of the biological model requires knowledge of computer programming, therefore a graphical user interface consisting of several easy to use screens was developed to simplify data input and make the biological model more accessible to producers and professional animal scientists. The complete package represents an easy to use decision support tool that predicts nitrogen, phosphorus, and potassium excretion in beef feedlots, in response to breed, management, and different dietary formulations.