Steps for Evaluating a Hay & Grain Based Ration

There are many ways to evaluate a ration. The example outlined below illustrates a simplistic approach. It is presented to give an introduction and feel for the ration evaluation process. Consult with your nutrition professional or veterinarian when evaluating your diet. Many factors come into play including the condition of your horse, environment, etc. Solicit professional advice to help you use your feed analyses most effectively.

The horse in this example is an 1100 lb. thoroughbred, ridden and trained mainly for English pleasure events. Although all components should be evaluated, for simplicity’s sake, we’ll just focus on crude protein (CP).

Hay and grain have a similar dry matter content (about 90%). As such, the ration will be evaluated on an as sampled or as fed basis. (For more information, see as sampled vs. dry matter basis).

1. Refer to the Nutrient Requirement Tables (NRC) to determine the daily protein requirements. Requirements are based on body weight, activity level, growth stage and reproductive status.
Protein required for 1100 lb. horse with light activity = 820 grams /day.
2. Weigh feeds to determine amounts fed, then calculate grams of protein supplied.
All values as sampled basis
Lbs. fed CP,% CP, grams/lb. CP, grams fed
Hay 16 6 27.2 435
Grain  6 12 54.4 327
Total 762
3. Calculate deficiency or excess:
Daily CP supplied 762
Daily CP required 820
Difference  -58
The ration is short 58 grams.
4. To reduce the deficit, one option is to purchase grain with a higher CP and slightly adjust the feeding rate.
Substitute a grain with 14% CP.
All values as sampled
Lbs. fed CP,% CP, grams/lb. CP, grams fed
Hay 15   6 27.2 408
Grain  7 14 63.5 445
Total 853
5. Calculate deficiency or excess:
Daily CP supplied 853
Daily CP required 820
Difference +33

The grams supplied (853) are now sufficient to meet the daily requirement with a slight excess.

This is a simple illustration of using analytical values to evaluate your ration. Other factors such as body condition, health history and environmental factors should be taken into account to best design a sound ration for your horse. Consult with your nutrition professional or veterinarian to help you formulate a ration designed to insure the health and longevity of your horse.