One source of inefficiency in poultry production comes from variation in feed ingredients. Using standard feed mixing techniques, grains and meals are each stored in their own bins (1-bin method). Linear programs are typically used to find the combination of ingredients meeting nutrient restrictions based on average ingredient compositions. To increase the probability of meeting nutrient restrictions more than 50 percent of the time, stochastic models may be implemented. For instance, feed cost may be increased by 20 percent to meet the minimum crude protein requirement in 80 percent of batches instead of 50 percent of batches. In-line equipment (such as NIR) is now available to quickly estimate ingredient compositions (e.g., percent protein) and facilitate improved formulation techniques.
This publication describes Microsoft Excel workbooks designed to calculate:
- The effects of dividing ingredients into above- and below-average portions (2-bin method), and
- The costs of providing nutrients at specified confidence levels.
By dividing ingredients into above- and below-average portions, efficiency is increased by improving performance due to under-feeding with below-specification batches of feed, and by minimizing waste from over-feeding.
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Click
to download the Stochastic Programming Workbook (1-bin method) tutorial
Click to download the Stochastic Programming Workbook (1-bin method) Excel file
Click to download the Stochastic Programming Workbook (2-bin method) tutorial
Click to download the Stochastic Programming Workbook (2-bin method) Excel file
Click to download the Crude Protein Variation Estimator Workbook (1-bin method) tutorial
Click to download the Crude Protein Variation Estimator Workbook (1-bin method) Excel file
Click to download the Crude Protein Variation Estimator Workbook (2-bin method) tutorial
Click to download the Crude Protein Variation Estimator Workbook (2-bin method) Excel file
Click to view the Truncated Normal Distribution Calculator
Status and Revision History
Published on May 28, 2014