Nutrient Requirements of Horses and the NRC

When equine nutritionists want to review a horse’s diet theyrefer to Nutrient Requirements of Horses producedby the Committee on Nutrient Requirements of Horses and published by theNational Academies Press – commonly referred to as “the NRC Requirements”.

Initially chartered by President Lincoln in 1863, “the NationalAcademy of Sciences, NationalAcademy of Engineering, Institute ofMedicine, and National Research Councilare private,nonprofit institutions that provide expert advice on some of the most pressingchallenges facing the nation and the world.

“Knowncollectively as the National Academies, our organization producesgroundbreaking reports that have helped shape sound policies, inform publicopinion, and advance the pursuit of science, engineering, and medicine.”

The Committee, made up of experts in the field of equinenutrition with input from stakeholders, sponsors and public commentary,reviewed and evaluated the information in the previous edition (1989) in lightof new information and advances in equine nutrition. 

Previous recommendations were clarified, and additionalinformation was added in several areas including expanded nutrient discussions,considerations for breed differences and in-depth evaluations of other factorsaffecting management, nutrition and ration formulation and evaluation.

The “NRC Requirements” provide guidelines that represent thebest-known available information.  Someof the requirements are based on established minimums known to prevent disease,similar to the model used in human “minimum daily requirements” while others,where there has been little or no research done with horses, has beenextrapolated from other species. 

The formulas used to develop the requirements in the DailyNutrient Requirements Table and in the online “Working Document” program cannot take into consideration every nuance of breed, management, climatic or feedavailability differences.  Theseguidelines should be used as a starting point – not a final result.

Any one who is serious about understanding equine nutritioncan benefit from including a copy of NutrientRequirements of Horses, Sixth Revised Edition in their library.  While the research evaluations can be heavyreading, the general discussions are rich in information and easy to follow.

The book - NutrientRequirements of Horses, Sixth Revised Edition, National Academies Press, isavailable at

Another very readable interpretation of NRC guidelines is UnderstandingEquine Nutrition by Karen Briggs available at and other onlinebookstores.

29 December, 2011