Working With a Nutritionist

Using a qualified equine nutritionist can help you manage your horses to live and work better.

Feeding horses properly is an art and a science. Sometimes it helps to work with a nutritionist to find out which grains best complement available forages, to design the best diet for a broodmare or a performance horse, or to resolve a nutritional problem. Why? Because sorting the best diet for your horse from the blinding array of commercial feeds and supplements, or from more than 100 basic feed ingredients last listed by the 2007 Nutrient Requirements of Horses, can be daunting at best, and dangerous at worst. But regardless of your horse's feed needs, Burt Staniar, PhD, assistant professor of equine nutrition at The Pennsylvania State University, says horse owners need to understand the building blocks of diet. "Not only must we supply proper amounts of certain minerals and protein a certain horse requires, but also be aware of energy in the diet and how it affects the horse's metabolism."

Feeding a horse is like building a house. You can buy all the lumber and other materials needed, but the house can't build itself. You need the means to put it all together, and energy is the driving force. "We must understand how the way we feed horses affects growth, maintenance, and performance," adds Staniar.

Horse owners often want to create their own rations, and a good nutritionist can help with this. He or she has the years of training to understand how these materials go together, and how to balance everything and make it come out right.

"Many things affect nutrition, such as environment and genetics," explains Staniar. "Genetics affects a horse's potential for growth or performance, but his environment is a crucial factor in reaching this potential. Management is a big factor; you must be aware of all the aspects of the environment and how they interact with one another.

"For example, with growing foals, when their pasture begins to decline, you may not see it right away," he continues. "The rough measurements we use, like weighing the animal, may not be enough. By the time we see a change in weight, much has already happened at the molecular level in the body. With horses, your long-term objectives are not just growth and weight, but longevity and athletic performance. You also need to consider physiological status (whether the horse is a pregnant mare, growing foal, competing athlete, or pasture pet)."


It's important to have a good feed or hay sample for proper analysis. A pelleted feed is easy, since the ingredients are well-blended. It's harder to get a representative grain sample, says Karen Davison, PhD, manager of equine technical services for Purina Mills. "If you take just one handful of a grain mix from one bag, the contents might vary, depending on where in the bag you pulled it out," she says. "It's best to pull a small sample from several bags and combine them to send off for analysis."

A hay sample is more difficult. A handful of hay from one flake might not be an accurate indication. That part of the bale, or the corner of the field it came from, might be weedy, didn't get as much irrigation, or had a different soil type. It's better to take a sample from several bales, using a hay probe, which you can borrow from your feed company rep or county extension agent. Drill into eight or 10 bales for core samples and mix them to have a good representation of that load of hay. For reliable results, good sampling procedures are important.

--Heather Smith Thomas

Karen Davison, PhD, manager of equine technical services for Purina Mills, says the only way to see if you are feeding horses correctly is to know everything that's going into them (hay, grain, and roughage/pasture). "Some people take a blood sample to send off for analysis to try to find out if they are feeding the horse properly," she says. "Blood analysis can be helpful in evaluating the level of a few nutrients, but for most nutrients it is not an accurate indication of diet.

"The body does many things to try to keep blood levels within a certain range," Davison explains. "For instance, analyzing blood calcium is of no value in determining whether diet is adequate in calcium. If it's low, the digestive system becomes very efficient in absorbing the little that's there, and the kidneys become more efficient in retaining rather than filtering out and excreting calcium from the blood. If the horse still can't manage blood calcium levels, certain hormones kick in and start pulling calcium from the bones."

Hair samples are also unreliable as an indicator of current diet, she says. "Several labs in the country will analyze hair samples from a horse and give you a complete mineral profile and mix up a supplement to fit that horse's needs," she says. "Years ago, when I was with Texas A&M, we pulled hair samples from a Paint horse to send in. We pulled white hairs and sorrel hairs from the same horse, and got different results from each color."

Amy Gill, PhD, an equine nutrition consultant based in Lexington, Ky., works with various feed companies and several large breeding farms.

"Working with a nutritionist can be a help to many horsemen," Gill says. "The marketplace can be very confusing; so much has changed in the horse feed industry in the past 20 years. We've gone from doing our own grinding and mixing on the farm to using technology for having feeds already put together and balanced for a variety of nutrients. There are also a multitude of supplements."

The horse owner might want to talk with a nutritionist just to make sure a horse's diet is on target. "Your retired horse and your new competition horse must be fed differently because of their different needs," Gill stresses.

Most horse owners overfeed, and this has led to metabolic syndromes, Cushing's disease, insulin resistance in horses and foals, and animals prone to obesity and laminitis. So a big push now is away from starchy grains and using more soluble fibers and fats. Gill reminds horse owners they need to focus on forage first since the horse is a grazing animal.

Educating owners about proper nutrition is Gill's main focus as a nutritionist.

"For clients (breeding farms, racehorse training facilities, etc.), I deal with specific things like growth, exercise, and metabolic disorders," explains Gill. "Some of the problems are nutrition-related and some are management; seeing the management practices enables me to make helpful recommendations. Depending on which company's products they like to use (and she says it doesn't matter which the client chooses), I match the product with the horse's needs, or I can put together a concentrate for them that will balance their forages. In most situations there's a feed company that carries a product that will work for their purposes, but they need to pick one that's designed specifically for the type or class of horse they are feeding."

Stephen Duren, MS, PhD, founder of Performance Horse Nutrition in Weiser, Idaho, travels to horse farms all over the world as a consultant. "Most of my consulting falls into three categories-- working with feed companies, horse owners, and veterinary clinics," he says.

"The vet is often the first person to realize that a horse or farm has a nutrition problem, or has it brought to his/her attention by a client," says Duren. "I get a lot of calls from veterinarians asking me to help with a particular situation."

Finding a Nutritionist

Horse owners can find a nutritionist through various avenues, including feed companies. "Even though a nutritionist works for a certain company and may recommend those products, they are very qualified people and know what they are talking about," says Staniar. "Check with your local feed store to ask about their suppliers. Most nutritionists at these companies keep up with the latest science."

Duren says company nutritionists can answer basic questions or help finding a nutritionist. "If you are using their product, they should be able to steer you to a nutritionist," he says. "There is a commercial bias when you go this route, because they want you to use their product. That's not necessarily bad; you just need to realize they are likely to make all their recommendations around their own product."

Some companies don't have a well-trained horse nutritionist; their expertise might be cattle or swine. Extrapolating from one species to another can lead to problems. If you are going to work with a nutritionist, make sure he/she is an equine nutritionist. Also make sure the person has a graduate degree in equine nutrition.

If you don't want to work through a feed company, you can find an equine nutritionist through a university animal science program or extension service, says Staniar. "Often there are extension seminars you can attend," he adds. "If you live in a state that doesn't have a strong equine program, someone in the animal science department could recommend a nutritionist in another state."

You can usually find some of these university/extension resources via the phone or Internet. Depending on how busy that person is, advice should be free (paid for by your tax dollars). Many of the university specialists are busy teaching and conducting research, however, and you might not get the details or follow-up you need.

"The best situation is to find an independent consultant who can come to your farm," says Staniar. "You'll probably get your greatest level of help from someone who has been to a lot of farms and has experience in various situations to evaluate.

"A nutritionist may have to come to your place and evaluate the whole picture," continues Staniar. "The solution to a nutritional problem, or developing the best diet for a group of horses, is not always simple. It involves evaluation of how the animals are kept, their environment, their (physiological) status, what they are being fed, etc. We'll take samples of pasture, hay, feeds being fed, sometimes even soil samples, and all those tests must be paid for. It takes time to bring all that data together and come up with recommendations on how the nutrition and management may need to be changed."

Duren adds, "If someone hires me, they hire me as their own. I don't bring a bias of products I want them to use. I evaluate what they are doing, make suggestions, and give an objective overview. They are paying me for that service. The fee depends on time involved--whether I'm working with a few horses or many, and whether it's something that will take a significant amount of time to evaluate."

Lab fees are charged directly to the farm; these are about $45 per sample for a forage or grain analysis.

"I wrote a software program to evaluate feeds and give the client a printout--a complete nutrient profile that shows how much of each ingredient is being fed, total amount of those ingredients, nutrient requirements, and what the diet is providing, in tabular and graphic form," says Duren. "We make a stall card with feeding instructions for each horse. If I run diets for weanlings, yearlings, pregnant mares, lactating mares, 2-year-olds in training, etc., I just charge so much per printout.

"When I'm brought in, there's usually a problem that needs to be resolved," continues Duren. "The farm may have DOD (developmental orthopedic disorders), habitual colic problems, poor reproductive success, or some other problem, and we're doing more forage analysis. If I actually go to the farm, there's a day-rate fee associated with that."

When Davison finished graduate school and worked for Texas A&M and the equine extension service, she often got phone calls from Texas horse owners needing nutritional advice. "They'd explain their situation, and many of them had a local feed mill that would make up the feed if I'd give them a formula," she says. The nutritionist can formulate a diet for your feed mill to make, then he or she should check it to make sure it's staying close to what you need.

Most horse owners want a commercial feed they can buy to fit their horse's needs, rather than have to formulate a feed mix themselves. If you only have a few horses, it's simpler to buy pre-mixed feed.

Check the Qualifications

Staniar suggests horse owners look at qualifications of the nutritionist they consult. "Some people who call themselves nutritionists don't have training," he says. "A veterinarian has a degree in veterinary medicine and must be licensed to practice. A nutritionist doesn't need a license; anyone can call themselves a nutritionist if they want to. But they need a graduate degree in equine nutrition or animal science. That's why it's often safest to go through your vet, feed company, or a university to find a good one."

Long-Distance Advice

If your farm is not large enough to justify paying a nutritionist to make a farm call, you need to give as much information as possible about your feeding program when you're working with the nutritionist over the phone, says Davison. It's a good idea to have a hay sample and feed sample analyzed, even if you have a feed tag. "Then when you contact a nutritionist, you can say you feed X number of pounds of this kind of feed and this kind of hay and fax the analysis," says Davison. "You can describe what kind of work you do with the horse, and any particular concerns. The more information you give, the better. Every time someone calls me to ask what they should feed their horse, that's just the beginning of a long conversation, and I have to ask a lot of questions."

The nutritionist needs to know everything the horse is eating, including pasture and supplements, to get an accurate picture and know what might be lacking or which nutrients might be in excess of requirements.

"The thing that helps a nutritionist most is detail--accurate weights and history," says Duren. "If the horse has a problem, I need the vet's dismissal sheet or client report sheet, etc., so I have an idea what's going on with that horse. If the client has thought about this in advance and has the horse's history on paper, that saves a lot of time and money. He can e-mail or fax me the horse's history and a list of things they've been doing and feeding."

Once the nutritionist makes recommendations, it is important to follow them. As Duren points out, whether you follow the advice might not be a life or death situation, but it definitely can mean a sound versus unsound horse, or an "also ran" versus a winner.

He has formulated some very unique feeds to deal with certain horses' problems. "There are feeds designed especially for the underweight or overweight horse, and new feeds that are low in nonstructural carbohydrates to help horses with carbohydrate-related problems," says Duren. "The technology is there to create whatever is needed."

Take-Home Message

Most of us could use some help in understanding how to best feed our horses, whether they are old pasture pets or champions on the track or in the show ring. Even having an annual evaluation by a nutritionist--and following that advice--could result in healthier horses. For those animals having problems such as weight loss or developmental disease, a good nutritionist can even make the difference in their survival and future health.

About the Author

Heather Smith Thomas

Heather Smith Thomas ranches with her husband near Salmon, Idaho, raising cattle and a few horses. She has a B.A. in English and history from University of Puget Sound (1966). She has raised and trained horses for 50 years, and has been writing freelance articles and books nearly that long, publishing 20 books and more than 9,000 articles for horse and livestock publications. Some of her books include Understanding Equine Hoof Care, The Horse Conformation Handbook, Care and Management of Horses, Storey's Guide to Raising Horses and Storey's Guide to Training Horses. Besides having her own blog,, she writes a biweekly blog at that comes out on Tuesdays.

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