This Shiny application is a practical decision-support tool for formulating beef cattle diets using nutrient requirement equations based on NASEM (2016). It is designed to help producers and nutritionists evaluate animal requirements, feed options, ration cost, and nutrient adequacy in an integrated workflow.
Animal and nutrient requirements: Users enter animal information such as body weight, target average daily gain, finishing stage, pregnancy status, or lactation status. The app estimates dry matter intake and key nutrient requirements for the selected animal.
Core calculator: Users select animal type, enter mature and current body weight, and provide additional information when needed (age, gestation month, lactation month, or work intensity). Users choose feeds from the library (including user-defined custom feeds), enter amounts in kg, and the app computes daily nutrient requirements, nutrient supply, balance (deficit or excess), and the percentage of requirements met for macro-nutrients.
Diet formulation: Users select available feeds and enter feed prices, inclusion limits, and fixed ingredients when needed. The app uses least-cost optimization to formulate a ration that meets selected nutritional targets.
Ration evaluation: Results include feed amounts, nutrient supply and balance, dry matter intake, estimated feed cost, and selected nutritional and safety checks.
Scenarios and reports: Users can save and compare ration scenarios, add farm-specific feeds, and generate producer-oriented ration and batch-feeding reports.
Guide video: Watch
Reference: National Academies of Sciences, Engineering, and Medicine. 2016. Nutrient Requirements of Beef Cattle: Eighth Revised Edition. Washington, DC: The National Academies Press.
We welcome your feedback!
If you identify any mistakes, errors that need correction, or have suggestions to improve the model's predictive accuracy, please don’t hesitate to contact us. We are also interested in hearing your thoughts about the tool and its usefulness in your work.