Phillip Erickson, an engineer in Idaho Falls, Idaho, kindly took on the challenge of designing a spreadsheet that would eliminate all the tedious arithmetic involved with the Purdue charts. Thanks a lot, Phil!
You can download the file (for free) HERE. (Just right-click on the link and save the file to your computer.) Although the spreadsheet was designed for Excel, I've also tested it using Lotus 1-2-3. As you can see from these screen captures, it has a few glitches in 1-2-3, but the basic functions still work. Here's how to use it:
At the top of the page, fill in your horse's weight (The owner's name, class of horse, breed and age are all optional, and are provided for your record-keeping benefit).
Next, go to the Purdue nutrition charts, locate the weight that comes closest to your horse's weight, and copy the corresponding nutritional information into the cells that are shaded green on the screen shot above.
When that is done, you are ready to start playing with the feed amounts. Type in the number of pounds of the individual foodstuff into the appropriate orange-shaded square, and when you click on another cell, the spreadsheet will automatically re-calculate the nutritional data at the bottom.
If your horse is on pasture, you can assume he or she is eating the normal amount that the spreadsheet calculates under "Lbs per day" when you enter your horse's weight. Simply enter that number of pounds after the type of hay that best describes your pasture. For hay, a common rule of thumb is that a bale normally weighs about 40 pounds and is divided into a dozen flakes. Thus, an average flake would weigh about three and one third pounds.
After you have entered the amount of feed, look at the bottom of the chart.
Negative numbers indicate that the minimum requirements have been met. Those numbers show how far "to the good" you are.
A positive number shows that the ration may fall a little short in that area. If your horse weighs less than the weight on the Purdue charts, however, small positive numbers may still be adequate. (Remember, this is not rocket science... You just need to be in the ballpark!)
In this example, feeding three-fourths of a 40 pound bale of early bloom Timothy hay per day meets the minimum requirements for that 1100 pound horse in almost all areas. The only exception is a nursing mare -- which can easily be solved with a small amount of calcium and other supplements.
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COPYRIGHT © 2006 BOB LEMEN, GRAND RAPIDS, MINNESOTA. ALL RIGHTS RESERVED.
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