The Norfor Model

The NorFor Model is an evaluation system, used for ration formulation and economic optimization. It is based on scientific methods and knowledge.

The NorFor model can be divided into five parts:

1) an input section which describes animal and feed characteristics.

2) a module that simulates processes in the digestive tract and the intermediary metabolism, termed the feed ration calculator.

3) a module that predicts feed intake.

4) a module that predicts the physical structure of the diet.

5) an output section that describes nutrient supply, nutrient balances and production response.

Energy is calculated as net energy for lactation and both ECM and protein yields are predicted. Interactions between animal characteristics, feeding level and feed composition are taken into account when calculating the nutrient supply. This implicates that energy and protein values for individual feeds are not constant or additive.

With the NorFor model, feed rations are formulated by a non-linear economical optimization. This means that NorFor finds the most economic combination of feed ingredients which meet the nutritional requirements. It is possible to optimize from 84 nutritional variables in NorFor, but the default setting in the national clients are eight nutritional constraints.

The NorFor model makes it possible to better predict the “true” feeding value of a ration. This enables a more efficient feed utilization with economic as well as environmental advantages. The NorFor Model is available as an IT solution which is upgraded whenever new knowledge is developed.

For general information about the NorFor model:

Please contact Tone Roalkvam, CEO


Table of contents (pdf)

Chapter 2

Overall model description (pdf)

The NorFor book is available for purchase on the