Folks talk about putting weight on or building topline on a horse. First let’s talk about what fat, muscle and topline really mean.
Muscles move bone. Muscles can be increased by correct exercise to challenge the muscles, combined with proper nutrition to fuel muscle repair and growth.
Fat is entirely different than muscle. Horses store fat under the skin (subcutaneous) and in the abdominal cavity (visceral fat), as well as in the muscle tissue (think marbling on a steak). To add fat to a horse, you feed more calories that the horse is burning. The horse’s body stores the extra calories as fat.
Topline refers to the area from the withers to the tail along and on top of the spine. Topline is mainly formed from muscle development, although fat deposits contribute.
Body condition in horses is most often assessed using the Henneke scale.
Keep in mind also that a horse can be lean yet very fit and well muscled, or can be fat and unfit, or a variety of mixes of muscle development and fat reserves.
The most concentrated calorie sources are grains (carbohydrates) and fats. High-carbohydrate low-fat grains like corn, oats and barley produce an insulin spike while the body digests them, then the body actually spends energy to convert the extra calories into fat stores. Large grain meals also have the potential to create digestion problems. Fatty grains, nuts and oils are digested and used more slowly for energy, and are more easily converted by the body into fat stores. Looking at the diet of wild horses, the diet is generally low in carbohydrates and sugars, and also fairly low in fats, except for seeds and occasionally nuts.
Two important points before we talk about specific foods to fatten up a horse. First, horses do not have a gall bladder like humans do. The gall bladder holds bile, and releases the bile to help digest fats. Bile is made by the liver. When a human eats a high fat meal the gall bladder can release a large amount of bile to deal with the fat. Horses have a constant slow drip of bile, as horses are meant to be eating throughout much of their day, and eating a low-fat diet. So, when feeding fats to horses, the fats should be given in small amounts and spread out over several meals. Second, not all fats are equal. Some fats actually create inflammation in the body, and may aggravate conditions like arthritis. Other fats reduce inflammation. The omega-6 fats increase inflammation, and omega-3 fats reduce inflammation. Ideally, the diet should have a ratio of between 1 and 4 parts omega 6 to 1 part omega 3.
Black oil sunflower seeds (BOSS) are about 40% fat. However, the fats in BOSS are mostly omega-6 fats, which can cause inflammation in the body. BOSS is also very high in phosphorus, so a free-choice mineral buffet or very careful ration balancing is necessary. I have fed horses anywhere from a handful to 4 cups of BOSS daily. BOSS can be fed dry, soaked or sprouted.
Soybeans are typically around 8% fat, and a moderate fat source. The omega-3 to omega-6 ratio in soybeans is more balanced and less likely to cause inflammation. I use a cold-extruded soybean pellet and feed just a handful to a couple cups. My preferred soybean pellets can be fed dry or soaked. Some people have concerns about using soy. I addressed this in a separate blog post here.
Chia seeds are about 31% fat and have an excellent omega-3 to omega-6 ratio. (The drawback to chia is the expense.) Chia is fed by the ounce (very roughly 2 tablespoons). Most horses benefit from just 1/3 cup or roughly 2 ounces daily. I prefer to feed chia dry, rather than soaked.
Alfalfa and other legume (plants that are able to create their own nitrogen supply) hays, at only 2% fat, are less-efficient calorie sources.
For readers in other countries, if you do not have access to chia or roasted or cold extruded soybeans, look for high-fat seeds safe to feed to horses that have more omega 3 fats than omega 6 fats. Feed in moderation only, as horses do not have a gall bladder to handle large fat meals. Increasing carbohydrates by increasing grain will also add fat. Be aware of the possible side effects of a heavy grain diet, especially causing mineral deficiencies and over-acid body pH. Both of those set the horse up for arthritis and injuries.
Adding muscle: Proteins are used to build muscle. Proteins are chains of amino acids. Of the 22 amino acids, 10 are important for muscle building, with lysine, threonine and arginine being most important. Lysine is highest in soybeans and alfalfa, making those feeds the best way to bring up the protein level and build muscle. Soybean is 26% protein minimum and alfalfa can range from 15-25% protein depending on maturity. Black oil sunflower seeds (BOSS) are about 22% protein, but are low in lysine and the other muscle-building amino acids, so BOSS is not the best muscle building option. Chia seeds are 23% protein and high in lysine and would be great for adding muscle. Rice bran and rice bran pellets are high in lysine. However, rice bran may have solvent residue from the oil extraction process and rice is the most polluted grain crop right now. Rice is heavily irrigated, and picks up the pollutants in the irrigation water and from the soils, including heavy metals like lead and cadmium. All rice has been found to have arsenic (horse dealers used to feed arsenic to make the horses fat and shiny, and the horses would then quickly lose weight and die after being sold). Another good source of muscle-building proteins are supplements with high amino acid content, like regular formula horse Dynamite.
Healthy topline involves all the principles of adding muscle, plus correct exercise and ruling out medical issues. There are many possible ways to exercise a horse to increase topline. In general, the horse must be traveling round, with his back lifted, his neck arched, his poll the highest point of his neck, and his hind hooves stepping well up underneath him. Exercising on moderate hills can be very useful. I have some older blog posts about conditioning my senior horses. Horses that fail to develop topline in spite of correct diet and exercise should have their teeth checked, their saddle fit checked, their hoof trims evaluated, and finally be checked for Cushing’s disease.
Further considerations about grains, fats and hay:
In the USA, not all grains, fats and hay are equal. The quality of soybeans, alfalfa, BOSS and grains can vary considerably. In the case of soybeans, the majority of soybeans sold in the US today are genetically modified, also called GMO. GMOs are a controversial topic, and each goat person must do their own research and make their own decision. For myself, I feel there are enough studies available now showing the harm GMOs can cause, especially to the very important gut organisms, that I will not feed any GMO products. Soybeans need to be heat treated before feeding as well, to a fairly specific temperature. Too hot, and you reduce the nutritional value. Too cool and the trypsin inhibitors are still active, which makes the soybean toxic. Additionally, most soybean in livestock feed these days is soybean meal, which means the oils have been solvent-extracted. This reduces the fat content and potentially leaves behind a solvent residue.
Alfalfa has also recently become available as a GMO crop and has the same potential drawbacks as other GMO crops.
BOSS is sometimes treated to inhibit sprouting, either by cooking or with chemical sprays. If in doubt, soak a handful and see if they sprout in a couple days. Healthy BOSS suitable for feeding should sprout.
Among the grains, oats and barley are still fairly chemical-free and not yet available as GMOs. Barley does need to be rolled to remove the pointy awn at the end of the seed. The quality of barley and oats depends on the health of the soil they are grown in. Look for large, heavy plump grains, and if possible, check with the local farmer to see what sort of fertilizer program is followed. The standard N-P-K approach to fertilizer does not put sufficient minerals back into the soil.
Corn is almost entirely GMO at this point. ‘Nuff said. Look for organic corn, or heirloom corn varieties.
So, what do I feed to my own horses to build muscle or add body fat?
I use a combination of a pelleted grain ration and cold-extruded soybean pellets. The grain ration contains corn, oats and barley. The company avoids GMOs, and their grain mill is entirely chemical-free and certified organic. The whole extruded non-GMO soybean pellets are cooked to the correct temperature. I also feed locally-grown non-GMO alfalfa, and BOSS. The pelleted grain ration also contains montmorrillonite clay as a pellet binder, which helps absorb any environmental toxins and also repels internal parasites. I also offer my horses my favorite regular vitamin/mineral pellets, which is high in amino acids.
If I did not have access to these specific products, I would feed local organic roasted soybeans or chia seeds (to build muscle) and BOSS (for the fats), and add oats, barley and/or organic or heirloom feed corn as needed. I would mill in or topdress montmorrillonite clay. I would also make 10% of their daily hay ration non-gmo alfalfa or a similar legume hay for the amino acids and to offset the phosphorus in the BOSS. If I still needed to build more muscle, I would also add a multivitamin mineral supplement with lysine, threonine and arginine.
Want to learn more about equine nutrition? Confused about how to transition your horse to a chemical-free lifestyle? Interested in more information about feed label interpretation? Join me for convenient international teleclasses coming January 2019! Details at https://wellness.barakah.farm/services
These statements have not been evaluated by the Food and Drug Administration or American Veterinary Medical Association, and are not intended to diagnose, treat, cure or prevent any disease. Always consult your veterinarian about any changes to your animal’s health program.