Feeds labels include a guaranteed analysis, and supplements include that same guaranteed analysis or the amounts of active ingredients. Have you ever wondered what these statements actually mean? Why some are minimums while others are maximums? And what about the units? What the heck is a ppm anyway? While on the one hand understanding this information may not seem particularly important, in reality, if you can decipher this part of a label or feed tag you can make far better-informed purchasing decisions.

Let’s start off with how these are regulated. Feeds are regulated by each state’s individual feed laws and, therefore, what must be listed on the guaranteed analysis will vary somewhat from state to state. However, most states have a lot in common. The guaranteed analysis is where the manufacturer states what nutrients they are guaranteeing you, the consumer, in the product, so it is worth paying attention to!

Most feed manufacturers will state the percentage of protein, fat and fiber as a starting point. Fiber is always listed as a maximum and protein and fat as minimums. This is because fiber is relatively cheap, and if minimum fiber was allowed the product could just be full of relatively indigestible fiber. Meanwhile, protein is an expensive ingredient and if it were given as a maximum, the feed could realistically have very little protein.

Also listed as percentages are the macrominerals calcium, phosphorus and, in some cases, salt or sodium and magnesium. Exactly which macrominerals are listed will depend on the state’s laws. Some allow the collective term “ash,” which is the sum of all the minerals in the feed. Other states require them to be listed out individually, or only individually if ash is over a certain percentage of the total feed. Some states allow salt to be listed, while others require sodium be given on its own. Because calcium and phosphorus are so important to bone health, these two are nearly always given, and calcium is typically given with a range of minimum and maximum, while other macrominerals are given as minimums.

The trace or micro minerals comes next. There are states that have no requirement for these minerals to be listed. Many manufacturers will list them out anyway, since they know today’s consumer is becoming more informed and wants a greater level of detail about what is being fed to their horses. Typically copper, zinc and selenium are listed and it is less common to see manganese. Again, trace minerals are given as minimum values and often on feed tags the unit “ppm” is used. PPM is also used on some supplement labels and stands for “parts per million,” a pseudo unit used to measure tiny quantities. One ppm means one part per one million parts. Another way of describing ppm is milligrams per kilogram, meaning that for every kilogram of feed, the stated number of milligrams of that mineral will be included.

Trace minerals use these tiny units because the daily requirement for them is in milligrams, whereas macro minerals, such as calcium, are required in gram quantities each day. Understanding ppm can be tricky, but it is worth taking the time to get to grips with it because what can look like a very large amount of a mineral may in fact only be a tiny quantity when feeding the manufacturer’s daily serving. This is especially true of supplements where very small ounce quantities tend to be fed each day.

If your supplement states on its guaranteed analysis or list of active ingredients that a one-ounce serving provides 750 ppm of zinc, it is easy to think that this is a fabulous product for use in rations needing more zinc or for horses with hoof or skin issues where zinc is important. However, it is vital to remember that ppm always stands for milligrams per kilogram (mg/kg). So, if you feed 1 kg of this supplement you will indeed provide your horse with 750 mg of zinc. Remember though that this product has a 1 ounce serving size. One ounce is just over 28 grams. A kilo is 1,000 grams. If we divide 1,000 by 28 we find that there are 35.7 ounces in a kilo. By dividing 750 mg (the amount of zinc in a kilo of this product) by 35.7, we determine that there are in fact only 21 mg of zinc per serving. Suddenly this does not look like such a great source of zinc, especially when you consider that the average 1,100 pounds horse requires a minimum of 400 mg of zinc per day. This supplement will barely make a dent in that requirement.

Because ppm can be confusing and requires you to do some math in order to really understand what you are feeding your horse, we believe in being a little more transparent. That is why all our EnviroEquine supplement labels give the amount in milligrams of trace minerals per serving. Even though the math to convert percentages to grams is easier to do, we don’t want you worrying about that either, so even our macromineral levels are listed out in grams per serving.

While feeds list their entire ingredient list together and then a collective guaranteed analysis, supplements may list out active ingredients with their amounts and then inactive ingredients with no amounts. This is not to say that the ingredients in the inactive ingredients have no nutritional value, but rather the manufacturer is stating that in this particular product those ingredients are not included because they are integral to the products supposed benefits to the horse. Inactive ingredients may be such things as alfalfa meal, flax or vitamin C that are included as carriers for the active ingredients or to prevent their oxidation.

The guaranteed analysis or levels of active ingredients tell you what the product will provide to your horse. They allow you to compare across products in similar categories. Be wary of products, especially supplements, that use ppm on a per serving basis if that serving is less than a kilo because the numbers can be very misleading.

If you are not sure whether you are feeding the correct levels of important nutrients such as trace minerals, vitamins and the like, then consider having a qualified equine nutritionist review your horse’s ration. Nutrition consultations with our consulting equine nutritionist Dr. Clair Thunes, Ph.D. are available here.