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What is a good all-around diet for show horses?

What "basic" formula would you recommend for a barn containing mostly show horses that travel to shows 2-3 times monthly (hay, grain, supplements)? The animals are in good general health and are under 20 years old. The barn does not give any more than a handful of grain to their horses twice a day and does not feed any supplements. They give hay and about 2 quarts of beet pulp per day. All the horses maintain weight on this diet, except the older ones. What's your opinion on beet pulp? As far as I know it can be a hay substitute and some people add it in the feed in the winter to help increase bulk. Bulk of what? Could you please clarify? Could you also answer how often should hay be analyzed for nutrient content?


I strongly feel that hay should be the majority of the diet. Many horses can survive without any extra supplementation at maintenance if their hay is of good quality. Analyzing hay is difficult because many barns get a variety of hay and don't usually have one load of hay which lasts all season. Technically, to be sure of your hay’s quality you should test every load; however, that is not practical. If a barn has a load of hay that will last all season they can have it tested. (See the Rutgers Fact Sheet on analyzing hay for horses.)


However, if you know the species of grass in the hay and the basic quality (poor, good or otherwise) you can get a rough idea of its average nutrient content from the databases at


Most horses should eat 2% of their body weight daily (total diet). Hay should be at least 1.5% (if not more) of that ration. For example, an average-sized (1,000 lb) horse should eat about 20 lbs of feed each day, 15 lbs of which should be hay. The rest of the diet can be grain, etc.


Most horses, if they are exercising moderately, can get by with about 2 to 5 lbs of a commercial mix per day. I usually recommend a high-fat feed (about 10%) for exercising horses. There are many on the market nowadays. However, some horses are easy keepers; they don’t need much grain and could probably get by without it. If they are demanding more food, you can feed beet pulp. By adding a pound or two of dry beet pulp (which can be moistened to help with water intake and, when moist, serves as a great base for adding supplements) you can increase the amount of fiber in the diet without adding excess calories. Just make sure the beet pulp does not have added molasses. In doing this you will also be providing them with a meal at the same time as the other horses in the barn so they will not get agitated when the others are fed.

Replacing hay with beet pulp is not exactly a great idea. Horses still need their roughage, i.e. hay and pasture, which slows down the passage of feed through the digestive tract and allows for a slower consumption time. Roughage is what keeps horses from being totally bored all day (and it also keeps them from eating fences). The only difference between roughage and fiber is their absorption times.

I don't usually recommend feeding additional supplements to the average light working horse. I usually recommend adding supplements only in certain circumstances:

  1. When feeding poor quality hay. Hay and pasture are where horses get most of their vitamins.
  2. When horses have very limited access to pasture. The concentration of vitamins in pasture is quite a bit higher than it is in hay and grain.
  3. When a horse is more nervous or stressed than usual (e.g. from an intense show schedule, traveling long distances, intense training), or is generally a nervous horse
  4. If a horse has any performance problems including muscular or nervous system problems.


There are many other factors that go into developing a feeding management program for the individual horse; these are just brief guidelines for feeding horses in general. For more information on feeding horses please see our nutrition fact sheets.


Answer provided by Carey Williams, Ph.D., Rutgers Cooperative Extension.




Is it okay to feed bread to my horses?


Is it okay to feed bread to my horses? If so, how much can I feed per 100 pounds of body weight?




"Bread" is a rather wide category – just look at the aisles in the grocery store. Everything from high carbohydrate fortified white bread to rye and high fiber/low carb breads with a wide variety of flavors, nutritional contents, etc. is out there. That being said, most breads are grain-based, which is what we feed horses anyway. They tend to be high starch - indeed, the standard for determining glycemic index (blood sugar response) in human medicine is based on white bread.


However, because there are a wide variety of recipes out there, I hesitate to generalize over all types of breads for horses, since, to my knowledge, there have been no feeding trials conducted using even white bread in this species. "Bakery waste" (day old products or batches that didn't come out just right) is frequently used as a mainstay of hog and cattle rations in some areas. Some commercial feed companies have even included bakery waste in their horse feeds in the past. The only reason it is not commonly done now is for fear of getting poppy seed or chocolate in the mix too, which can cause positive drug tests in performance horses.


Since commercially available breads are meant for human consumption, they will not contain known toxins or impure ingredients and frequently are supplemented with added vitamins and minerals (including safe amounts of selenium). They can actually be more nutritious than plain grains commonly used for horses! Wheat is a grain not commonly used in horse rations due to price and concerns about potential problems with glutens in its raw form. Although wheat flour is a main ingredient in most bread, it is acceptable, especially in the baked, processed form of bread. Unless fortified with calcium, breads may not have a good calcium to phosphorus ratio, but this would not be a problem in most cases if they were fed with good quality hay or pasture. In very old horses the lower calcium intake might actually be good! Day old bread and bagels are commonly fed to horses in Europe as a treat or cheap supplement to their rations.


My main concern with feeding a lot of bread to horses would be the potential lack of fiber, leading to wood chewing and perhaps gastric ulcers and a possible calcium deficit. Before everyone starts raiding the stores for their day old bread and bagels, let me give the following recommendations:

  1. Avoid breads that contain poppy seeds or chocolate, especially if competing with the horse.
  2. Try to get the high fiber/low carbohydrate fortified types of bread.
  3. If planning to feed more than a few slices a day, start slowly. I'd probably restrict intake to 1-2 pounds a day unless there is a special case, like a toothless horse.
  4. If the horse is prone to laminitis or is glucose intolerant I would not recommend feeding anything but high fiber/low carb breads in very limited quantities (no more than one or two slices a day, and not all at once!).
  5. If feeding over 5 pounds of bread a day, consider getting a nutritional analysis of it (especially if feeding a mixture of "waste" bread) and consulting an equine nutritionist to make sure it is balanced.
  6. Stay away from the high sugar/high fat donuts unless you have a horse that:
    • Is not glucose intolerant
    • Is a bit thin and needs to gain weight!

Answer provided by Sarah Ralston, VMD, Ph.D., dACVN, Rutgers Cooperative Extension.



What is the best way to balance a broodmare’s diet for calcium and phosphorus?

I live in Wyoming in an area that has a low phosphorous to calcium ratio. It’s almost to the point where foals are born with crooked legs if the mare is not supplemented with phosphorous. I have not had much luck getting mares to eat high phosphorous supplements. I feed grass hay in winter and pasture May through October. For a mare in foal, what would be the proper mix of beet pulp and wheat bran to achieve the right balance of calcium to phosphorous?


The grasses in your region usually have a calcium:phosphorus ratio of at least 3:1. Even grass hays in the Front Range of the Rockies tend to have at least 1% calcium, which, if the mares are eating at least 25 lbs a day, would give ~120 grams of calcium. I assume you are feeding horses which are between 1100-1300 lbs adult weight. This would exceed their calcium needs by about 3 times, so supplementing beet pulp for the added calcium would probably not be necessary.

They will require between 26 to 32 grams phosphorus total in their ration to meet their needs but could tolerate up to 60 grams total safely. So assuming only a small portion of phosphorus is provided in the grasses (~0.15% = 18 grams in 25 lbs) you easily supplement up to 3 lbs of straight wheat bran (1.18% Phosphorus, gives you only ~18 grams) which should meet their needs. However, I am also assuming you will also feed a grain-based concentrate balanced for broodmares mares in their late pregnancy/early lactation that would also contain added calcium/phosphorus so you could feed less bran. It would be safest, however, to get your hay analyzed to determine if the calcium and phosphorus content is close to these estimates.


This answer was written with the help of Sarah Ralston, VMD, Ph.D., dACVN, Rutgers University, Equine Science Center.



Can you explain how digestion produces heat?


Can you explain how digestion produces heat? Do grass and hay produce less heat than corn? Does digestive heat have an adverse affect on performance?



The "heat increment", or metabolic heat generated in the body tissues (muscles, etc.) during the process of energy utilization is highest for protein, moderate for starches and very low for fats. The heat of fermentation that is "lost" in digesting fiber and any other carbohydrate source that reaches the large intestine is not as big of a concern. This is because it is generated primarily in the intestines and does not affect the larger muscles as much as the direct heat generated in the muscles during exercise does. (It does help keep them warm in winter!).


It is important to know that corn does not produce heat. It actually has a lower heat increment than oats! The fermentation of fiber in the large intestine generates a lot more heat than is lost in the process of converting the starch in corn to glucose. Putting it through the metabolic pathways is where a bit of heat is generated each time a chemical bond is broken, but the actual ‘heat’ is not significant.


In extremely hot or humid weather, horses with heat dissipation problems run a potential risk of adverse effects from feed heat increments. If your horse is unable to sweat (anhydrotic), obese or heavily muscled, or dark-colored, performing fairly intense exercise (lots of trotting or faster paces) for 30 minutes or more can put it at risk. If your horse falls into this category, feeding free choice good quality grass hay, water and white salt might ease the load a bit.


To minimize the internally-generated heat that needs to be dissipated primarily through sweat loss in the summer, avoid excess protein (10-12% max) and excessively fibrous hay. Fresh pasture is lower in fiber, therefore it requires less fermentation and will not create as much heat. If the horse needs more calories to maintain weight, consider a higher fat (10-12%) concentrate or high fat supplement, but beware - hot, humid summer weather may turn your supplement rancid quickly. A half-cup to a cup of corn oil will do just as well and be less likely to go rancid since you can seal and refrigerate the bottle.


Answer provided by Sarah Ralston, VMD, Ph.D., dACVN, Rutgers Cooperative Extension.



My horse is eating dirt; what could be missing in the diet?

I have a new off the track Thoroughbred. She has been getting 10 quarts of a commercially formulated feed that is split up in two meals a day. I am in the process of cutting back on this and providing free choice hay. She has been eating dirt by the mouthful every time I turn her out. I introduced to her a mineral block, and we added magnesium to her diet to see if that could be the problem. I have been trying to look up what minerals she could be lacking. She has a great amount of weight on her, so that's a good thing! Do you have any suggestions?


It is probably good old sodium chloride (salt) that is missing. Provide your horse with a container of loose salt (preferably non-iodized), but limit access to only 2 to 4 ounces at a time. If it really is a salt deficit, your horse might overeat initially. Gradually increase access until your horse is no longer craving it. The trace mineral blocks provide other trace minerals that your horse does not need in large amounts. If it eats enough to correct salt deficit, that will be in excess of other mineral needs. Plus the blocks are fairly abrasive, which is not a problem with everyday use, but if salt needs are high, it is difficult for a horse to easily lick enough off and they will start to bite at the block.


The other possible deficiency is phosphorus or calcium. Start the horse on some alfalfa hay or pellets and give it a bran mash. Since the horse is already at an adequate weight, it is recommended to gradually cut out all of the grain and replace it with timothy/alfalfa hay cubes.



How do I slow down a horse’s eating time?

I have a problem feeding our two horses. The older horse has more of an appetite than the younger one. When we feed the older horse his grain, he meets us at his feeding station, running as fast as he can and grunting vocally all the way. He eats very rapidly, often throwing or slinging his feed. Then he moves to the younger horse’s eating station, runs him off and finishes his meal. The younger one just moves in submission. How do I safely overcome this problem?


The best thing to do here is to try to slow down the dominant horse's eating habits. A good way to do this is by placing either large round stones (3” to 5” around), or small salt blocks in the bucket with his feed. This will force him to sift around the rocks to get to the feed and will slow down his rate of consumption, allowing your other horse to consume his feed in more time. If he gets frustrated and leaves his food for the other horse’s you may want to consider tying him near the bucket for the duration of feeding time. This of course is dependant on how well he ties! If he has any tendency to back up and break halters, etc. this would not be a good option.


Another thing that could help is to supplement his feed with hay cubes. They are a great fiber source, so they would not hurt at all, and they take a longer time for the horses to consume. This works the same way as the rocks in the feed bucket - only now the horse is actually consuming something.


Answer provided by Carey Williams, Ph.D., Rutgers Cooperative Extension.



Can a horse eat eggs?

I was talking with an old racehorse trainer today and he said he used to give his horses eggs regularly. It made their coats look terrific. As my hens are laying like crazy and providing more eggs than friends and family can use, I was wondering if the extra eggs could be given to my horses?


Eggs are an excellent source of protein, as we all know. One egg per horse per day would definitely not hurt-if you can get them to eat them! I don't know if it would be easier to feed them raw (which would be easier to mix into feed) or hard boiled (to reduce the risk of salmonella). The shells could even be ground up as a calcium supplement. I believe they used to feed eggs to horses in England and Ireland.


Answer provided by Sarah Ralston, VMD, Ph.D., dACVN, Rutgers Cooperative Extension.



What are good energy sources for horses?

I told someone that protein doesn't give horses energy, that fat does along with a good exercise program. I would like to know if I am correct and what else would be a good energy source?




This is basically correct. Calories from protein utilization usually account for only 10% of the horse’s total energy expenditure, which is minimal. If provided in excess of actual amino acid needs, protein is broken down and utilized as an energy source, but it releases a fair amount of heat and ammonia in the process that must be eliminated. Fat is a very energy dense calorie source, so feeds like rice bran (26% fat) or a vegetable oil (100% fat) are good at adding energy density to a horse's diet. But the normal horse ration has only 3% fat and horses do not have a gall bladder to help regulate the digestion of fat. You can add up to 10% fat to a horse’s ration, providing up to 25% of its total calories, but the amounts of fat fed must be increased slowly and carefully. Volatile fatty acids from the fermentation of fiber in the large intestine and soluble or simple carbohydrates (sugars and starches) are the most common sources of energy for horses. Fiber sources (pastures grasses and hays), though not as calorically dense as the sugar/starch sources (grains), should be the main source of energy in any horse’s ration. Indeed, for most horses, grasses and hay contain only 12% protein, 3% fat and 20% soluble carbohydrates, which will be more than adequate to meet their nutritional needs. Sugars and starches from grain- based concentrates are easily broken down to glucose and used directly for energy or stored as body fat and, in much smaller amounts, glycogen which is also used for energy. However there is increasing scientific evidence that feeding large amounts of grain (over 4 or 5 lbs per day to an average sized horse) has drawbacks, such as contributing to the formation of stomach ulcers, increasing the risk of colic and perhaps other metabolic problems and behavioral vices. To increase your horse’s energy level, feed good quality hay/pasture, perhaps some grain-based concentrate, and make sure you have a proper conditioning regimen for your discipline.




Are the fat and protein in my feed causing my horse to be 'unruly'?

I bought a horse a couple of months ago. It was a little thin, its coat looked dull and its hooves were dry and cracking. The horse looks much better now with proper nutrition and plenty of grazing. My question is this – if I give the horse feed that is high in protein and fat, will it make it hot and unruly? I started to notice it was getting a little hard to handle when I rode it and was sweating quite heavily with minimal exertion. I backed off on the feed and started cutting it in half with oats. All I know is, the horse doesn’t seem to be as hot. I use a biotin supplement for its feet and I feed the horse about 6 lbs of feed per day plus all the hay and grass it wants. Is this a good diet with proper nutrition for this horse? I want to maintain the weight on the horse now, plus provide proper nutrition. Of course – I don’t want the horse to become unruly and resistant because of the feed I am giving it. Can you help me decide what a good daily feed plan should be?


It sounds like what happened is that when the horse was finally being fed the right nutrients in a balanced diet, it felt better and had more energy! It wasn’t necessarily the fat and the protein in the feed; it was just the feed in general. Fat is a good energy source for underweight horses because it has more calories per gram than carbohydrates; however, it has a much slower release of energy than carbohydrates, so it doesn’t cause the same burst of energy that feeding something like corn would. Protein is not really ever used as an energy source (only 15% of our total energy normally comes from protein) unless the body has no other choice (i.e. starvation or certain diets like the human Atkins diet). So the protein in the feed is definitely not the problem. Excess sweating is actually a good thing; the time you need to worry is if the horse doesn’t sweat enough. It probably isn’t used to this much work or having this much energy to be utilized towards work.

Adding oats to the feed you are giving the horse isn’t the best idea. What you are doing is essentially diluting the nutrients that are concentrated in the commercial feed. The high fat, protein and other vitamins and minerals are now much lower in the total feed because oats are not as concentrated. As long as the horse has access to plenty of pasture or good quality forage, you should not be at risk for any nutrient deficiencies because most forages contain more than adequate amounts of vitamins and minerals for an adult horse. Watch that the horse doesn’t start gaining too much weight. You probably can back down on the grain you are feeding assuming the horse is now in good body condition.


Answer provided by Carey Williams, Ph.D., Rutgers Cooperative Extension.



What part of the fiber eaten by a horse is absorbed?

In reference to the terms “absorbable,” “digestible,” and “fermentable,” what part of the fiber eaten by a horse is absorbed? Is it absorbed after digestion and fermentation? Would “lignin” refer to the type of fiber?



Fiber is a carbohydrate. The main building block of carbohydrates is glucose, a simple sugar. Starches (e.g. most of the carbs in grains like corn) are just long chains of glucose linked together in a fashion that is easily metabolized, or absorbed (transferred from the gut to the blood stream) in the small intestine. Sugars and starches like this are digested (broken down to glucose by enzymes) and absorbed. Fermentation (an enzymatically-controlled transformation of an organic compound) by bacteria and other microbes only occurs in the cecum and large intestine.


Fermentation is mainly required for products composed of more complex carbohydrates, e.g. cellulose, hemicellulose and lignin (the types of fiber found in hay and pasture). These possess glucose chains which are linked together in more complex ways and are therefore more difficult to break. Thus, they must be fermented by bacteria instead of digested by enzymes.


Beet pulp and rice bran are high in rapidly fermentable carbohydrates which have a combination of starches and celluloses that can be absorbed and fermented.


Answer provided by Carey Williams, Ph.D., Rutgers Cooperative Extension.



Is feeding fish extracts to race horses beneficial?

I work with an international racing authority and am in charge of the supply and management of equine feed. I was wondering if there were any benefits or side effects to feeding fish extracts to racing horses.



I have no direct experience with feeding fish extracts to horses, but there should be no risk with this type of product. The protein quality should be fairly high and highly digestible to horses. According to the 2007 NRC (Nutrient Requirements for Horses), fish meals contain 68.5 to 71.2% protein. They are an excellent source of lysine, which is good for growing race horses. They also contain 5 to 10% fat, which is a good energy source for them as well. I was surprised to see the meals are also high in Calcium (4 to 5%) and Phosphorus (2 to 3%), which would also be good for growing bones. (Menhaden and anchovy are the only fish extracts studied in horses.)


All in all, the fish meals would appear to be a good source of desired nutrients for racing/growing horses; if they will eat them. I do not think they would confer an "extra" advantage when racing, other than allowing balancing for optimal nutrient intake.


Answer provided by Sarah Ralston, VMD, Ph.D., dACVN, Rutgers Cooperative Extension.



How can I encourage my horse to eat and gain weight?

I have imported a 7-year-old gelding from Germany and he has arrived in poor condition, having lost a great deal of weight before arrival. I plan to treat him for possible ulcers, but I also wanted to know what I can do to stimulate his appetite and encourage him to eat. How I can best put weight on him so that he can begin training?


Putting on weight is one problem; getting him to want to eat is another. It is hard to give any exact recommendations without seeing him or at least knowing how thin he is. The ideal Body Condition Score (BCS), on a scale of 1 to 9, is a 5. If he is really thin (BCS = 2, very little to no fat over neck, withers, shoulder or tailhead, and ribs are easily visible with no fat cover), you need to start feeding very slowly. I would recommend this protocol:


Feed low quality hay to start (high fiber, low protein)

  • Day 1-3 = 50% of total energy needs (about 10 lbs), spread this over feedings every 4 hrs
  • Day 4-5 = 75% of energy needs (about 15 lbs), spread over 4 feedings
  • Day 6-10 = 100% of energy needs (about 20 lbs), spread over 4 feedings
  • Day 10-30 = 100% of total energy needs. Increase hay quality (use a good quality grass hay or alfalfa mix) over 3 feedings
  • Note: it takes about 2 months to change 1 BCS (or about 50 lbs).

If the horse is over a BCS 3 (tailhead prominent but vertebrae cannot be visually identified, ribs with slight fat covering but still easily seen, shoulder, neck and withers with fat cover) then you can begin to add grain in the first week, but I would wait until the good hay is meeting 100% of his energy requirements for his current body weight (about day 10). You probably won't notice much weight gain in the first thirty days, but it should take off after that. It does take time to ramp the anabolic processes back up.


I don't recommend straight alfalfa - they don't need that much protein (10 to 12% is fine). An alfalfa mix would be preferred for its palatability, energy and protein, but be careful not to overwork his kidneys. I highly recommend finding a feed that is high in fat and fiber instead of one high in soluble carbohydrates. Most feed companies have at least one on the market. These are very palatable feeds that he should enjoy eating. If you are still having problems getting him to eat the hay, try adding alfalfa/grass mix hay cubes. They can be broken up and soaked to help soften them. But he really should be eating as much hay as he wants in about two weeks.


Answer provided by Carey Williams, Ph.D., Rutgers Cooperative Extension.



How can I get my horse to gain weight?

I own a six year old mare. In the four years that I have had her, she has received roughly the same feed regimen: 8 quarts of sweet feed a day, daily wormer, tube worm twice a year, alfalfa hay in the winter months, sometimes alfalfa cubes or pellets in transition during spring. There have been no problems with this regimen. She looked the same all through winter, but this week she has a marked weight loss. I have added another 8 quarts of sweet feed and another scoop of alfalfa cubes to the morning feeding and paste wormed again. She still is not showing signs of improvement. There is no feed loss (e.g. when teeth need floating).What am I doing wrong?


I think the hay might be the problem. Since you have already checked her teeth and deworming program, I have a couple of suggestions you can try.


First, it is important to know that horses need to consume at least 2% of their body weight daily, so if your horse is about 1,000 lbs she should be eating about 20 lbs of feed every day. At least half of that should be hay or another form of roughage. Start out by getting a kitchen or bathroom scale to measure the amount of feed she is currently getting (including hay and grain). Once you weigh the feed you will be able to get a better idea of what you need to do.


If she is not receiving an adequate amount of feed, my first suggestion is to check the hay quantity. Horses should be offered at least 1.5% of their body weight in hay daily. I would add a high quality grass forage or a grass alfalfa mix. The hay should be soft with more leaves than stems. (Grass hay should not have a lot of large seed heads.) This will indicate that the hay has more protein, vitamins and minerals than hay which is coarse and stemmy. If you determine that the hay quality is decent, make sure she is getting at least 1.5% of her body weight (15 lbs for a 1,000-pound horse) in hay.


Depending on how much exercise she is getting weekly you should try to keep the hay around 5 lbs per feeding. Since weight gain is the goal, you can try top dressing it with a fat supplement. This will add more calories than 16 quarts of sweet feed. My favorite fat supplement is rice bran, because horses rarely reject it and it is high in fiber. Adding rice bran will increase the fat content in the feed and will create more energy for weight gain without the effect of a high sugar diet (or no hyperactivity). Your horse could probably get about a pound or two per day, but because different types of rice bran vary it is good to follow the recommendation on the bag. “Stabilized” rice bran is fortified with a higher level of calcium since natural rice bran is typically low. However, since alfalfa cubes are high in calcium this shouldn’t be much of an issue for you.


Remember, you need to be careful when adding fat to the diet. You should increase the amount slowly over the course of 2 to 3 weeks. This is the standard time for any change in feed.


Try this for a few weeks to a month and monitor her condition. As with any horse, you should not be able to see her ribs, but you should be able to easily feel them when running your hand down her side. Her top line should also have a fat cover without bulging or rippling. If her condition still does not change, or she still is not eating, I would try adding an extra flake or two of hay or bump up to 3 lbs of rice bran. Remember to do so slowly and be patient; weight gain takes a long time.


Answer provided by Carey Williams, Ph.D., Rutgers Cooperative Extension.



How do I get my Clydesdale to gain weight?

We have an 8-year-old Clydesdale gelding. He weighs around 2000 lbs. and I ride him about once a week. He has always been hard to keep weight on, but lately it seems we are losing the battle as he continues to lose weight. We gave him some de-wormer and nothing came of it. Right now we feed him 1 can of oats and a fat and fiber feed twice a day. We give him 4 sleeves of hay twice a day also. Do you have any hints on how to get some more weight on him?


I have a couple of suggestions you can try. First, it is important to know that horses need to consume about 2% of their body weight, so your 2000 lb horse needs to eat about 40 lbs of food every day! I would start out by getting a kitchen or bathroom scale to measure the amount of feed he is currently getting, hay and grain included! Since I am not sure how much your can of grain or fat and fiber feed weighs or how much your 4 sleeves of hay weigh, I am going to make a lot of assumptions here. Once you weigh the feed you will be able to get a better idea of what you need to do.


My first suggestion is to check the hay quality. Make sure he is getting a high quality grass forage; the type doesn't matter as much as making sure that it doesn't consist of a lot of stems or seed heads. The hay should be softer with more leaves than stems. This will basically tell you that the hay has more nutrients in it (i.e. more protein, vitamins and minerals) than something very coarse and stemmy. If you determine that the hay quality is decent, I would suggest increasing the amount of hay he is getting fed daily to AT LEAST 1.5% of his body weight (or 30 lbs). If he is already at this amount with the 4 sleeves twice a day, you can increase that to 35 lbs. If he is not consuming all the hay you are providing, you may have to try another forage source to make up for what he will not eat. In this case I would recommend hay cubes (either grass or alfalfa) or beet pulp. You can feed either moistened and in the same amounts you would need to make up the difference in the total 30 to 35 lbs. The other 5 lbs of the diet can be your fat and fiber with oats, split over multiple feedings.


Try this for a few weeks and monitor his condition. As with any horse, you should not be able to see his ribs, but you should be able to easily feel them when running your hand down his side. His top line should also have a fat cover without bulging or rippling. If his condition still does not change you can add rice bran to his grain feeding with the fat and fiber feed. This will increase the fat content in the feed again and will create more energy for weight gain. For a horse as big as yours you can feed up to about 4 lbs/day if necessary. However, you need to be careful when adding fat to the diet; please increase the amount slowly over the course of 2 to 3 weeks (which is the standard time for ANY change in feed).


Answer provided by Carey Williams, Ph.D., Rutgers Cooperative Extension.



How do I go about glycogen loading my horse?


How do I go about glycogen loading my horse?




Please do not attempt glycogen loading in your horse! Not only does glycogen depletion and repletion not work by the same mechanisms as it does in humans, but this practice could also be detrimental to your horse’s health! Problems such as colic, laminitis, and tying-up are just the beginning of the list of risks to the horse. Simply increasing the carbohydrate concentration in the diet without simultaneously adjusting the training regimen does not alter muscle glycogen stores. One study performed fed diets containing 15, 25, 33, or 42 % starch to horses in training (galloping) for 16 weeks and found no difference in postfeeding muscle glycogen concentrations (Topliff et al., 1987).


If you are interested in sparing glycogen for intense exercise, the best way to accomplish this is by increasing the level of fat in the horse’s diet. This is called “fat adaptation” (using an increased level of fat during exercise training). During your training sessions, increased fat will be used as an energy source in place of glycogen. This way, when it is time for the race or other intense exercise, the glycogen stores will be available for the critical time of need.


You can increase fat in your horse’s diet in a couple of ways:

  1. Look for a “high fat” commercial feed. Usually these can be found >8%, but I usually recommend 10-12% fat.
  2. Top dress your existing grain with a fat source, e.g. vegetable oil (corn oil is the most popular - use up to 2 cups per day), or rice bran (which will increase fiber in the diet, and can be purchased at a feed store.)

When adding fat, you must start off gradually. For example, if adding corn oil, you can start with 1/4 cup and increase it by about 1/4 cup every 3 to 4 days.


Fat adaptation takes about 4 to 6 weeks for the total benefits to be seen, but it is much healthier and more effective than glycogen loading.


Answer provided by Carey Williams, Ph.D., Rutgers Cooperative Extension.



How much hay and grain should I feed per day?

I have a horse in a stall that is not on any pasture. Do I feed him hay and sweet feed? If so, how much should I feed per day? He is 9 years old and weighs about 1050 lbs. Also, how can I tell if he has foundered before?



Unfortunately, without knowing how much and what type of feed he gets, how often and how long he is exercised, what type of riding you do, and whether or not he is fat, thin, or gets any turn out at all, I can't make very specific recommendations. Here are some general guidelines:


Horses kept in stalls should be offered at least 1.5 to 2% of their body weight in hay per day (15-20 lbs for your horse), assuming they are in good body condition and the hay is of good quality. To minimize waste and reduce boredom the hay should be offered in 3 separate feedings of 5 to 7 lbs. This is usually done with a breakfast, lunch and dinner-type feeding. They should have free access to a salt block and clean water at all times. Concentrates such as sweet feed should be offered only in amounts needed to maintain good body condition in addition to the hay and may not even be necessary if the horse is an "easy keeper". I tend to recommend high fat (8-10%) and fiber (>12%) pelleted feeds for such horses because the sweet feeds contain a lot of sugar that seems to make some horses a bit hyperactive. Most horses seem to do well on only 1 to 2 lbs of concentrates per feeding.


If you suspect your horse might have foundered you should definitely get a veterinarian out to see him. Foundering horses, depending on the severity of the founder, will act as if their front feet hurt - rocking their weight back on their hind legs to take the pressure off their front feet. They may or may not be willing to walk or trot. If it is severe they may lie down more than usual and be unwilling to walk at all. If it is acute (sudden) their feet may feel warm. If it is very chronic, you will see raised ridges around their hooves and a dishing (concave) appearance to the front of the front hooves. Again, you must get a veterinarian out to see the horse!


Several helpful publications on basic horse nutrition are listed here:


Answer provided by Sarah Ralston, VMD, Ph.D., dACVN, Rutgers Cooperative Extension.



How much hay and grain can I feed my Percheron?


I have a 2-year-old Percheron who doesn’t get a lot of exercise, except when out to pasture. I feed him a low starch grain and a grass and alfalfa mix hay. How much of each should I be feeding him? He weighs 1600 pounds.



It is hard to give an exact recommendation without knowing a bit more about your horse. For example, what is his body condition? Is 1600 lbs a good weight for him, or is he overweight? What amount are you feeding now?


If he is at a good weight and not increasing or losing weight I would stick with what you have been doing. When not exercising, most horses do well eating 2 % of their body weight each day. Assuming that 1600 lbs is an adequate weight for him, you would feed 32 lbs of feed/day in his case.


Most non-exercising horses that are easy keepers, as most draft horses are, can also get by with a forage-only diet. If you try this route, remember that his forage intake (the pasture he is turned out on and hay when in a stall) should total 32 lbs. For example, if he is outside for 1/2 of the day on grass, then the other 1/2 of his meal should be 16 lbs of hay. If he is outside all day long I would only feed the hay if the grass in the pasture is poor. In this case, you can get by with about 4 lbs or so depending on how much he will eat.


There are so many unknowns here that it is hard to give an exact recommendation, but I would try to stick with a forage-only diet and watch his weight. Draft horses can be prone to obesity, especially if not exercising.


Answer provided by Carey Williams, Ph.D., Rutgers Cooperative Extension.



Are there health benefits to feeding horses hay before grain?

I recently hired a new barn manager whose feeding practices differ from mine. I have always given the horses hay as soon as I get to the barn in the morning, then grain. When they are finished eating they get turned out. Since I have 18 horses, some of them might not get turned out for ½ hour to 1 hour after they eat. My new barn manager wants to give them just grain while they are stalled and have them eat their hay after they get turned out. I know the reason she wants to do this is to keep the stalls easier to clean, which is acceptable to me only if it doesn’t have an impact on the horses’ health. Could you please advise?



There is a nutrition myth that hay must be fed before grain. However, this does not have an impact on horse health. The only time it might make a difference is with horses that bolt their grain. Feeding hay first will help slow their eating down as well as slow down their digestive process. However, no research has shown that feeding hay before grain will have any other impact on horses.


The exception to the rule is for horses that consume ½ or more of their diet as grain. This is not recommended. In this situation, feeding hay first will help -- but it is always recommended to divide the meals into smaller feedings throughout the day. This may also help horses with a history of colic.


Answer provided by Carey Williams, Ph.D., Rutgers Cooperative Extension.




Will high iron levels in water trigger laminitis?

I have a question regarding high iron levels in well water used for drinking water for horses. My 20 year old Cushing’s horse is insulin resistant and had an episode of laminitis last year from which he fully recovered; we brought his insulin to low levels. The farm I am thinking of moving him to has high iron in the water. One can see it in the water buckets; some of the water is clear with iron rust sitting on the bottom of the bucket. It is well water and not filtered. I have read information on various websites stating that in areas where iron is high in water, there seems to be higher cases of horses that get laminitis. However, I cannot find any actual studies done on this issue. Have you heard of this issue regarding iron in water and the potential for it to trigger laminitis?



There is no scientific evidence that the high iron commonly found in New Jersey well water is a cause or risk factor for laminitis. The article mentioned cites correlations only, no evidence of causality. We had a similar problem with the well water at Rutgers in the early 90's. The research horses were all in good general health despite the metallic scum on the water buckets, and none of them foundered. The research horses did, however, have low (though within normal limits) red blood cell counts that responded to supplementation with copper (15 mg per day) and zinc (30 mg per day). As suggested in the article, the high iron might interfere with copper and zinc utilization, but if one is providing a commercial feed or supplement, almost all of them contain added copper and zinc. Read the labels on the feed bag to be certain. It may be wise to ask a veterinarian to monitor the horse's red blood cell count for a few weeks after the move.


Another potential problem is that the horse might not like the taste of the high iron water and may not drink enough to maintain optimal hydration during the first week or so. If you can get it accustomed to a masking flavor, like peppermint oil or apple juice in its water (not electrolytes) before the move, adding it to the new water may help. Watch closely for dry feces. Soaking its hay in the water will also help increase its intake and acceptance of the new flavor.




How do I get my horse to lose weight?

I have a 14-year-old Arabian gelding. He has gotten very fat over the last two or three years. I stopped giving him any kind of grain two years ago and it didn't seem to make a difference. He does not get a lot of exercise due to my work schedule. He is out on pasture six months out of the year and on hay the other six. I have been looking for grass hay but it is hard to find around here. I work 12-hour shifts so I am gone a good part of the day. Is it OK for him to be on the dry lot for that amount of time and on pasture for the rest? I'm not sure how I should begin to lower his weight. I am currently trying to lunge him for some exercise. Could you give me some helpful hints?



Your situation is a very common one that can be turned around by strict management. The lunging will definitely help him; I usually encourage as much exercise as physically possible for both you and your horse. The next step is to reduce the amount of feed intake per day without jeopardizing the vitamin and mineral balance. When feeding all-hay diets it is easy to know where to start because you can weigh the hay and then start cutting back a pound at a time. Most horses should eat around 2% of their body weight (e.g. 20 lbs for a 1000-lb horse). With overweight horses, I usually start by restricting their feed to 1.5% of their body weight or even 1% if the obesity persists. Managing pasture intake can be a bit more difficult as it is hard to determine how much the horse is actually eating. You can restrict pasture intake in a couple of ways depending on your farm setup:

  1. Turn out in a dry lot instead of on pasture. By restricting access to pasture by 6 to 12 hours a day you are reducing pasture intake by about ¼ to ½ of the total dietary intake.
  2. Keep the horse in a stall, sand arena, or round pen if a dry lot is unavailable. This is not as preferable as Option 1 and may lead to behavioral problems and/or gastric ulcers. Providing low-quality grass hay for the horse to munch on is probably better than leaving it alone in the stall with nothing to do.
  3. Use a grazing muzzle. This is the last resort and should be used if a dry lot or stall is not an available. Grazing muzzles are made so the horse can have limited access to grass but still be able to drink. This is a good option if the horse must be outside all day long.

The main concern with limiting intake to this extent is the possibility of creating vitamin and mineral deficiencies. To avoid this, feed a daily multi-vitamin and mineral supplement. Most companies make a supplement formulated for the average horse. The key thing to look for is a pelleted formulation. That way, you can supplement the product without needing to use grain as a carrier. If your horse will not eat this product alone, a small handful of moistened beet pulp (without molasses!) is the best carrier.


Dietary changes should always be made slowly. Decide on your management practice and make the total changes over the course of about 1-2 weeks. Gradually remove the turn out time, or increase the time the horse is muzzled. During the course of the weight loss is it best to monitor weight using a weight tape (available from any feed store) every other week. This will let you know if the horse is losing the right amount of weight or if you need to decrease turn out time even more. Once the right amount of weight is lost you can slowly increase pasture or feed intake until he starts to maintain his appropriate weight.


Answer provided by Carey Williams, Ph.D., Rutgers Cooperative Extension.



What is a good low protein diet for a horse with kidney disease?

My 25 year old Saddlebred has been diagnosed with kidney disease. I was able to get him to eat rolled oats and a little bit of sweet feed and first cutting grass hay. He’s eating the hay well. However, I am not sure if this is the best low protein, phosphorus and calcium diet?



You actually have the horse on a very good low protein ration right now. On the east coast, grass hay is usually less than 10% protein and less than 0.6% calcium if grown locally. Oats are about 12% protein; if lower protein is desired, you could use cracked corn (8 to 9% protein) instead. However, be aware that one “scoop” of corn will weigh almost twice as much as oats and provide more than twice the energy. Corn is actually a preferred feed choice for kidney failure, because it is a great source of calories with very little volume and extremely low calcium. Protein is only of major concern in advanced stages of kidney failure as a rule. The horse should definitely have access to a salt block and free access to water.
If your horse is maintaining weight on the current regimen, don’t change it. If it is underweight or losing condition, try switching (gradually) to the corn. If the horse’s hair coat starts to look dull and coarse, more protein may be needed. In that case, switch back to the oats or add in 4 to 8 ounces of soybean meal daily.




What can I put in my horse’s feed to mask the flavor of supplements?

My gelding will not eat his feed at all if it has supplements added to it. I have tried mixing them into a ball with molasses and alfalfa crumbs, but he will not touch it. Do you have any suggestions for getting him to take this supplement? Is there anything I can mix it with that he might eat?



If molasses doesn’t work, try applesauce in his grain with the supplement! That might help. He also might need a few days to get used to the new taste. If you don’t give him a choice between food with or without the supplement, after a couple of days he will figure out that he has to eat it!


Answer provided by Carey Williams, Ph.D., Rutgers Cooperative Extension.



How does a mare’s nutrition affect her milk production?


How much can I affect the quantity and quality of a mare's milk in the short term through feeding practices? What would happen if I were to cut back on my mare’s feed? Right now she is in good flesh.



The mare's nutrition does greatly affect her milk quality. The protein, fat, vitamin and mineral content of the milk is indicative of the composition of her feed. Her total amount of milk produced is determined by her nutritional status and how many calories she is consuming.


Lactating mares should consume about twice as much energy as they would normally need at maintenance (when they are not pregnant or lactating). They also need about 14% protein in their diet along with higher levels of minerals such as calcium and phosphorus (just to name a few).


Calcium and phosphorus are critical for the developing foal. As a foal grows it will lay down bone first. A lot of bone development takes place in the womb, but after birth this is where calcium and phosphorus are needed most. Also after birth, most of the growth is in the form of muscle, which is why adequate protein is crucial. Then, after all the developing bones and muscles’ nutrient needs are satisfied, any extra nutrients are used to lay down fat. Typically, if you are not supplementing a foal’s diet with any creep feed or other source of nutrients they will still need their mother’s milk for adequate growth of bone and muscle.


Answer provided by Carey Williams, Ph.D., Rutgers Cooperative Extension.



Should new hay be mixed with the old hay when introducing a new load?


For fifteen years I have always asked the barn manager to mix the old and new hays together when switching to a new load, especially since my horse has colicked a few times over the years from excessive heat, flu shot, too much alfalfa hay added during winter, and such. When I asked them to do so this year I was told that they no longer believed it needed to be mixed, so they elected to just give less of it in the stalls. Now my horse has loose stool. Do you think hays should be mixed when introduced?



It is never a bad idea to slowly introduce anything new to a horse’s diet. That includes new hay. Mixing the hay over the course of about a week would be the healthiest option for any horse, especially horses that are prone to digestive problems due to change in feed; although, your list of triggers indicate that the horse may be sensitive to a lot of other environmental triggers. Start by adding a small amount of new hay and removing a small amount of old hay. Then go to ½ new and ½ old, and finally mostly all new. This should help decrease the incidence of diarrhea.


Answer provided by Carey Williams, Ph.D., Rutgers Cooperative Extension.




Where do I find 'no starch' feeds?


I am having some issues keeping weight off my two mares. The facility where they are housed has beautiful pasture and, due to the wet season, it has been constantly rich in sugars. All summer and fall they have had muzzles on, but they still seem to be slowly gaining weight. I spoke with my veterinarian and he suggested a hay pellet with NO starch, low calorie diet. I currently have them on a low starch, low calorie diet with exercise 5 times a week, but with the winter season, their exercise will decrease due to outdoor ring conditions. I am having a very hard time finding a feed with no starches. I have only found low starch grains. Do you have any suggestions on where I could find the feed I'm looking for?



There is no such thing as a ‘no starch’ feed for horses. Carbohydrates make up the majority of all animal feeds including forages. Some grain-based products are formulated to have lower starch and/or sugar by not using molasses and replacing grains with forage such as legume or grass hays or high fiber ingredients like beet pulp. However, your horses probably do not need any grain at all. A good quality hay or hay cube can provide all the nutrients that a horse needs, as long as they are not growing, lactating or undergoing heavy exercise. The lowest starch type of forage is going to be grass hay or hay cubes. Usually these are made from timothy and/or alfalfa and tend to be a consistent source of nutrients, especially if selecting from a manufacturer instead of a hay producer. Cubes take a while for horses to consume, so the potential of boredom that could come from lack of long stem forage in the diet. I would also recommend trying to keep these horses in a dry lot to prevent them from eating any of the pasture grasses that may have a higher starch content this time of year due to the freeze-thaw cycle (day/night) and the overgrazing that can occur with the reduction of grass growth.


Make sure the horses are at least eating 1.5 % of their goal body weight (i.e. current a 1200 lb horse, with a goal weight of 1000 lb should eat 15 lbs per day) however, and it may be a good idea to also provide them with a vitamin and mineral supplement to make up for the lack of nutrients in the hay you are providing.


Answer provided by Carey Williams, Ph.D., Rutgers Cooperative Extension.




Are nuts and whole grains used in cereal and breads okay to use in horse treats?


I'm baking horse treats and was thinking about adding some cereal and whole grain bread to the base recipe. One concern I had was nuts and seeds. Are these safe to feed horses?



Bread and whole grains are perfectly fine to include in your horse treats. Whole grains used in breads and cereals such as oats, sunflower seeds, rye, etc., are fine. Most nuts (peanuts, walnuts, cashews, almonds, etc) should be fine as well in small amounts. Since you are making treats that will be fed in small amounts (less than 1 lb a day to the average size horse), any of these in moderation should be fine. However, please note that anything consumed in large quantities (over 0.5 % of the horse or pony’s body weight) that is not normally in the ration may cause gastrointestinal distress (colic).


Answer provided by Carey Williams, Ph.D., Rutgers NJAES Cooperative Extension and Sarah Ralston, VMD, PhD, DACVN, Department of Animal Sciences.




What’s the best way to feed a pregnant/lactating Draft mare and growing foal?

I am trying to insure that I have a healthy foal. I own a Percheron mare and have her booked to breed to a TB stud. I am worried about bone problems in the foal, namely, growing too fast. My mare’s had a few previous foals, all of whom are happy, healthy and full Percheron. However, her last foal (Percheron/Arabian) developed a condition due to rapid bone growth - his bones grew to where they affected his nervous system. His vet said that he could possibly outgrow the condition, but if not, he could have surgery performed when he was older. I know I need to be cautious in how I feed my mare while she is pregnant, but I want to be as proactive as possible. Can you lend any advice on how I should feed her prior to breeding, while pregnant, and then how/what the mare and foal should eat once the foal is born?


From the sounds of it, the colt developed "wobbler’s syndrome." Its cause can be partially nutritional, but it also has genetic and trauma components. Our draft crosses grow rapidly, but as long as their mineral needs are met we have had very few problems with growth abnormalities.


Based on our 7 years of data on this type of horse, my recommendations are:


1. Feed the mare a good quality grass/legume mix (alfalfa/clover) hay and, in the last few months of her pregnancy, a supplement designed for broodmares with extra minerals and low calories. There are several on the market. You don't want her too fat.


2. Once she foals, offer her the same concentrate feed that you plan on using for the foal (see below) in amounts that maintain her body condition (for the draft mares that may be as little as a couple of pounds per feeding if the hay is free choice and good quality). This way, if the foal steals her grain, it is still getting a balanced ration.


3. For the foal, start creep feeding a feed formulated specifically for growth (14 to 15% protein, and added minerals) as early as 1-2 months (preferably NOT a sweet feed) and look for some of the newer products that are higher in fat and fiber.


4. READ THE FEED LABELS! There are some "growth" products out there designed to be fed without hay or pasture - they will NOT contain the right concentration of minerals if you limit feed them with hay or pasture! We have tested alfalfa-based "Total Mixed ration cubes" fed as the sole source of nutrition for two years now and they worked exceptionally well, especially for the Draft cross types. But the weanlings did not do as well on them if they had access to pasture too. (Unfortunately the cubes are not yet available here in the east.)


There are many good products out there, but gain, be sure to read the labels. Feed 1 pound per month of age per day divided into 2 feedings up to 6-7 months. Do not feed more than 3-4 lbs of concentrates per feeding (6-8 lbs per day) after they are weaned.


If the foal is fat (can't feel his ribs, deep crease down his loin, bulging fat neck), cut back on the grain but do not completely eliminate it. Watch for signs of epiphysitis (enlargements just above the fetlock or knees) - that is an indication that he needs fewer calories and more minerals.


Do not let anyone try to tell you that the recommendation above has too much protein - It is a well-disproven myth that protein causes developmental problems. Do not feed a concentrate that is not formulated specifically for growth. Just because a product has 14% protein does not mean that it has the minerals needed for bone growth.


Answer provided by Sarah Ralston, VMD, Ph.D., dACVN, Rutgers Cooperative Extension.



How much protein does a horse need?


How much protein does a horse need, and what happens if they get too much? Also, what exactly is "crude protein?"



Horses at maintenance need about 8 to 10% of their diet to be protein. This will increase very slightly if exercising. If breeding, lactating or growing, the need can increase up to 16% at times. Feeding excess protein will not create a problem unless the horse has existing kidney problems. High-protein diets will cause high levels of ammonia to be excreted in the urine. If horses with kidney problems consume high levels of protein they could develop additional kidney complications. However, healthy horses should not have a problem eating high-protein diets. It is crucial that they be provided with free access to fresh water. Usually, diets high in alfalfa or another legume hay will contain excess protein (alfalfa can have protein levels as high as 25%). Most grass hay will contain enough protein to be adequate for maintenance horses; however this varies greatly depending on the quality and maturity of the hay.


“Crude protein” refers to the total amount of protein in the feedstuff. It does not represent the amount of protein that is “digestible” to the horse. Digestibility of protein varies between roughly 65 - 85% depending on which feedstuff is being digested.


Answer provided by Carey Williams, Ph.D., Rutgers Cooperative Extension.


What can I feed my old rescue horses to get them to gain weight?


I have three rescue horses; ages 23, 30, and 33. What should I look for in a commercial feed and supplements to help them gain and keep weight on? Each grain store tells me something different about the type of feed and the amount I should be giving them. Should I supplement with corn oil, beet pulp or anything else? If so, in what amount? They lose weight quickly and it’s been really hard to have them gain weight



If you haven’t already, you should have them checked by a veterinarian to rule out any problems which might affect their ration options
before changing their ration.


 Before you look at feeds, you should first look at the forage your horses are getting. Remember that a horse’s ration must be balanced around forage: good pasture and/or good quality hay fed at the rate of at least 1.5 % to 2 % of body weight per day (about 15 to 20 pounds for a 1,000 pound horse). Especially since they are all aged, have their teeth checked carefully for problems that would prevent them from prehending and chewing properly; if chewing hay is an issue, you could consider using hay cubes or pellets soaked in water as the primary forage source. Be aware they can eat up to 3% of their body weight in forage dry matter per day. If they are given free access to forage and still not maintaining adequate weight, then you will need to consider adding in a higher calorie concentrate.


The feed you choose will depend on each horse’s condition. Your rescues are on the older side. If they were still healthy and active, they could stay on regular adult feed, but if they are showing their age, you could start them on an extruded “senior” feed, which may be more easily consumed and digested. There is no “magic age” when you need to switch a horse to senior feeds; instead you must evaluate each horse individually. You need to consider teeth, body condition, and any medical issues (determined by a veterinarian) they may have. Assuming that liver and kidney function is normal, look for a feed with high fat and fiber (about 7 – 10 % fat, 10 – 14 % protein, and over 8 % fiber), formulated for the type of horses you are feeding, in this case, older horses that need to gain weight. Don't mix and match products.


Be sure to introduce new feed slowly. Substitute a pound of the new for a pound of the old feed until you are totally switched over. Without knowing the horses’ breeds and how much feed they are currently eating, it is hard to estimate the total amount that should be provided at each feeding. The average 1,000-pound horse’s stomach can handle no more than 5 pounds of feed at a time. Take a bathroom scale to the barn and weigh a scoop of what you are currently feeding against a scoop of the new feed.


The need for supplements will also depend on each horse’s condition after being on the new feed for a few months. Beet pulp is a good source of extra fiber but not a necessary component of a horse’s diet. Corn oil and rice bran are good sources of fat and will help to put
weight on your horses if the basal ration is not working; however, pick only one or the other-do not use both! If you choose a high-fat commercial feed, you may not need to supplement extra fat in any form. If you choose to supplement corn oil, you could start with ¼ cup per day and increase it over a few weeks up to 1 cup per day. If you choose rice bran, you could start with ½ pound per day and increase it over a few weeks up to 1 or 2 pounds per day, depending on the size of your horses. If the older horses are experiencing joint pain or arthritis, you could also look into a joint supplement.


Answer provided by Carey Williams, Ph.D., Sarah Ralston, VMD, PhD, DACVN, Department of Animal Sciences, and Laura Gladney, Program Associate, Rutgers NJAES Cooperative Extension.



Can you explain what proper blood Selenium levels in a horse should be?


I'm confused about selenium (Se) testing and desired blood levels. I've had my endurance horse tested about every two years for the last 6 years. The first test results according to my veterinarian were around 140 and I was told the normal range was 120-180. My veterinarian suggested I use a supplement to try to bring levels up to around 180 but that 200 would be safe. Once I switched to an organic based selenium (plus vitamin E) supplement, I found I could get levels up easily enough. A following test showed levels of 205, which another veterinarian told me was way too high, while another endurance riding equine veterinarian told me the range was appropriate for a hard working endurance horse. There seems to be a lot of disagreement in the equestrian world about selenium levels, with many in the endurance
field leaning towards the higher levels. Has any research been done recently on this subject? What level should I try to maintain when my horses are competing?

I keep reading that other horse owners get test results in the 17-25 range. Obviously there must be two different units for testing selenium levels. Can you explain the different test results? I'd like to be able to understand the selenium test results that various people talk about.


Bottom line is, selenium blood concentrations are notoriously difficult to assay and there are no good scientific studies of the efficacy of supplementation, and the amounts "needed". It is well established to be toxic in relatively low amounts (as little as 5 mg per day can cause mane and tail hair loss and horizontal hoof cracks that can lead to sloughing of the lower hoof wall). One should worry more about over- than under-dosing.


‘Normal ranges’ depend on the lab used and units in which they are displayed. Many reputable forage/diagnostic labs refuse to even attempt the assay because it is so unreliable. It is a waste of money to do the blood tests unless there is an apparent issue such as chronic tying up, muscle problems, and other indications that there might really be a problem. Feeding really poor quality hay or living in a region well established to be extremely selenium deficient like southern Florida or western Oregon may warrant a blood profile for selenium concentrations. As long as your horse is performing well, and is fed a reasonable, well balanced ration, supplementation should not be necessary.


This answer was written by Sarah Ralston, VMD, Ph.D., dACVN, Rutgers University, Equine Science Center.



How do I switch my horse from a high grain diet to one with less grain and more forage?


I am in the process of moving my horse, and its feed will change. I want to know the best way to do this. The horse is fit and a bit underweight. The former diet was 12 pounds a day of 12% protein and 3% fat feed with extra hay added but no pasture. The new diet will be 14% protein, 6% fat feed plus hay and pasture. I am concerned about changing out the grain from a lesser protein content. The horse is only worked for one hour, four times a week?

I would like advice on how to transition from the old diet to the new one.


These feeds are actually not that different. A 2% difference in protein, when factored into the entire diet, is not a significant a change. Slowly use the ‘pound-per-pound’ method (remove a pound of the old, add in pound of the new) over the course of a one-to-two week period. The biggest question, however, is what the final amount of grain should be - 12 pounds per day is a lot! Begin with eight pounds of the old feed at the new facility and start switching as the horse becomes acclimated to the pasture. Be sure to monitor its body condition. Introduce these adjustments slowly and if the horse starts to gain too much weight, cut back on the grain and supplements, not the hay or access to pasture. Any changes in diet will probably not be evident for a few weeks, maybe even a month, if the changes are slight. Keep track of changes with a weight tape and body condition score every other week.


Since mentioning that the horse could gain more weight, another method to decrease the amount of grain needed would be to add more fat to the diet above the 6% already in the feed. On an overall percent of the diet, when factoring in that the diet is mostly hay, 6% is still not that much. Therefore, one could supplement about six pounds of grain with one-to-two pounds of rice bran. Rice bran is high in fat and fiber, horses love it, and it really helps improve body condition. Adding rice bran may enable one to reduce the total amount of grain in the diet.


As for the pasture, introduce this to the horse slowly since it is not accustomed to lush grass. Begin this new routine by letting the horse graze for approximately an hour on the first day in the early morning, then gradually increase access to the pasture. Always start in the early morning hours when the grasses have their lowest sugar content until the horse reaches its full amount of time on the pasture. For example, it might take one-to-two weeks for the horse to fully adapt to a 12 hour turn-out. If monitoring the horse’s time on pasture is difficult one can also consider a grazing muzzle which will reduce the horse’s grass intake.




What type of hay and grain is good for a dressage horse?

I have two dressage horses that are allergic to alfalfa. One horse is in light work and does fine on turnout and crimped oats. The other one is an 11 year old Oldenburg gelding in full work and breaks out in hives. I would appreciate any advice on grain and hay!


We are not sure of your location; however, the best solution to finding hay appropriate for your horses would be to locate a good quality cool/warm season grass hay harvested before it became too mature. Grasses harvested before full maturity have more leaves than stems and higher protein/energy content. If living in the northeast, one can find a quality timothy or orchard grass. If living in the south, look for a good quality warm season warm season like Bermuda grass hay (some call it ‘coastal’ hay). In the western states Brome grass or oat hays may be more available. Another alternative would be to look for a clover mix hay for the higher energy/digestibility the hard working Oldenberg needs.


The horses described in this question should eat about 2 - 2.5 % of their body weight per day and most of that should be forage (pasture or hay). The remainder of the energy needed can be made up with grain. The horse that is in more work (and therefore needs more energy) can also be supplemented with a good quality grain mix. Remember to pick a grain that is formulated for its situation (i.e. adult maintenance versus intense exercise).


Answer provided by Carey Williams, Ph.D., Rutgers NJAES Cooperative Extension and Sarah Ralston, VMD, PhD, DACVN, Department of
Animal Sciences.




Can you explain how or why an injection of vitamin B complex stimulates appetite?


Can you explain how or why an injection of vitamin B complex stimulates appetite?




There appear to be two schools of thought on whether or not an injection of vitamin B complex will increase appetite. The vitamin B complex, specifically thiamin (B-1) and B-12, is responsible for the metabolism of the horse’s nutrients such as fats, proteins, and carbohydrates.


Symptoms of equine thiamin deficiency include abnormal slowing of heart rate (bradycardia), muscular incoordination (ataxia), localized muscular contractions visible under the skin, periodic hypothermia of the extremities, skipped heartbeats and loss of appetite and weight. There are no reported cases of vitamin B-12 deficiency in horses.


Other B vitamins that assist with the nutrient metabolism are riboflavin (B-2), and pantothenic acid (B-5). Riboflavin is required for the health of the mucous membranes in the digestive tract. Panthothenic acid assists some of the glands and hormones that aid metabolism of nutrients.


If your horse is experiencing Vitamin B deficiencies then an injection of the Vitamin B complex will definitely help by boosting the metabolism and allowing the horse’s body to use the food it is eating. But if your horse is healthy and not experiencing any deficiency then an injection of Vitamin B would most likely not do much for the horse, because the nutrients should be making their way through the system properly. In fact, if your horse is not deficient, an injection of Vitamin B complex would likely be a waste of money because Vitamin B is water soluble and any excess of it will be excreted in the urine almost immediately.


Answer prepared by Casey Lee, Cook College, Rutgers University.




Is it okay to feed watermelon to horses?


Is watermelon unhealthy for horses to eat? Will it make them sick?




There will be no adverse effects from feeding an occasional piece or rind from a watermelon. However, as with anything, if it is not supposed to be a usual item in the horse’s diet you always run the risk of them getting gastrointestinal problems (colic) from feeding too much of an unusual thing. So you are safe if you stick with using it as a treat every now and then, but don't make a practice of feeding them a whole watermelon daily.


Answer provided by Carey Williams, Ph.D., Rutgers Cooperative Extension.



How do I feed my weanling that will go into racing?


What specific dietary concerns should I worry about for a Thoroughbred
weanling that is headed for a flat racing career? Are there any supplements
to decrease stress and help keep the horse sound?



When a horse becomes a weanling there is a lot to consider. Now that the foal doesn’t have its mother’s milk to depend on for much of its nutritional needs, we need to supply them in the form of forages and concentrates. One of the most common mistakes we make is not feeding a high enough concentration of the critical nutrients (protein, calcium, phosphorus and some trace minerals) to provide for optimal growth. Weanlings require higher amounts of these nutrients on a per pound basis than an adult horse does and cannot eat enough of an adult formulation to meet their needs. 


Protein especially is one nutrient that is needed in higher amounts than for mature horses. It is a myth that too much protein will cause developmental problems. It has actually been scientifically proven to be just the opposite. If weanlings do not get adequate protein in their diets, growth can be stunted and developmental problems are more likely to occur. To provide adequate protein for a weanling, alfalfa and or an alfalfa/grass hay mixture should be used as the majority of the diet. Alfalfa, along with being high in protein, is also a good quality protein, so it will have the correct balance of the important amino acids that a growing horse needs (e.g. lysine and threonine).


Calcium and phosphorus are other minerals that need to be in a specific ratio for the young growing horse. A 2:1 calcium to phosphorus ratio is best. This is easy to accomplish if there is alfalfa in the diet; alfalfa has up to a 5 or 6:1 ratio, which is fine, however, under no circumstances should there be less calcium than phosphorus. An inverse ratio will cause the excess phosphorus to interfere with the absorption of calcium into bone.


Zinc, copper and selenium are also minerals that are needed in a particular balance; however, if the young horse is on good quality forage and a commercial grain supplement, there is no need to worry about any deficiencies. Feed companies have already fortified their grain- based products to provide adequate quantities. The only extra supplement that would be necessary is free choice access to a plain white salt block.


It is recommended that young horses eat at least 2% of their body weight in dry matter (feed without the water content). Weanlings should be offered at least 1.5% of their body weight in good quality forage and/or free access to good quality pasture. Depending on the quality and nutrient balance of the forage or pasture, concentrates formulated for growth (also known as “mare and foal” formulations) may be needed at 0.5 to 1.0% of their body weight, divided into two or more feedings a day.


The key to keeping the young horse healthy is to monitor its body condition. Learning how to body condition score is a good idea and there are many on-line sites that can help provide you with a guide. However, weekly evaluations will help you determine if you are feeding adequate energy needed to maintain a healthy body condition. A quick rule is if you cannot see, but easily feel the horse’s ribs, its diet is right where it needs to be. If you can start to see ribs or are unable to easily feel ribs, you may need to increase or decrease the feed accordingly.


If you maintain a balanced diet using these few guidelines, no other supplements should be necessary. However, as the horse grows and becomes a racehorse in training and actually starts racing, small changes may be necessary to increase the amount of energy in the diet, decrease some of the protein and balance the various minerals. As always it is best to work with a veterinarian that is comfortable giving nutritional advice or an equine nutritionist to properly balance your horse’s diet before making any drastic changes.


Answer provided by Carey Williams, Ph.D., Rutgers Cooperative Extension.



How do I get my young horse to grow taller, but not get fatter?


I have a question about my yearling (one year three months old). It is 3/4 Paint, 1/4 Appaloosa. The horse is being fed hay - continuous amount approximately 7 lbs a day - and about 4 lbs a day of development type grain and 1 lb of beet pulp a day over two feedings.  In the past four months, the yearling does not appear to have grown taller, just wider. It has been dewormed regularly. The veterinarian said to feed more food (mainly hay), but I'm worried about the horse becoming too fat. Should I add alfalfa to the feed? Or just more hay?



If your horse is in good body condition but the growth is stunted, it may be lacking primarily protein and calcium. I'd strongly suggest adding in some alfalfa, but do it very slowly. If the horse is indeed protein and calcium deficient, and too much is added too quickly, the horse will go through a growth spurt and potentially develop epiphysitis and/or contracted tendons. Add about 1 lb of alfalfa (in the form of either pellets, cubes or hay), divided into two feedings. Keep feeding this amount for two or three days, watching the horse’s legs carefully for signs of swelling around the joints or flexure deformity. If no problem occurs, add in another pound per day. Continue this routine until the horse is consuming 4 to 6 lbs of alfalfa per day divided into several feedings.



This answer was written by Sarah Ralston, VMD, Ph.D., dACVN, Rutgers University, Equine Science Center



Why would my veterinarian tell me to feed my young horse a low protein diet?


I adopted a BLM mustang that was only fed alfalfa; its dam was fed alfalfa while carrying and nursing as well. The horse had some tendon issues (slight contraction) when acquired at the age of 7 - 8 months. My veterinarian said to feed a low protein diet, so I put it on a bland grass hay diet. However, the horse lost weight, albeit, its tendons began to improve after I finally put him on a grain pellet for several months. Now it is on a diet of fresh spring hay, monitored grazing and a small amount of alfalfa cubes and oats. Thus far the tendons seem to be doing much better.


Can you tell me why a vet would recommend a low protein diet and no alfalfa?



Unfortunately that is an old myth about feeding young horses which began in the mid 1970’s and has persisted despite numerous scientific studies proving it to be false. Protein is necessary for proper growth of young animals. If one stops feeding young horses the protein they need, growth will be stopped or slowed. The growth process is what causes the developmental problems due to abnormalities either in the ration (usually mineral imbalances) and/or conformational defects (whether it is bone or tendon, etc.). If growth is stopped, the problems do not get worse. This is what low protein diets will do for young growing horses. If the underlying causes of the growth abnormality is not corrected, once the young horse is fed a ration that will support growth, the problems will re-appear. Young growing horses need higher levels of protein in their rations, than do adult horses, for optimal growth. Some of the developmental issues will come and go normally (i.e. epiphysitis or physitis, mild flexure “contracture” problems). Research on growth has shown that young horses need a 14-16% protein diet, but that high sugar/starch feeds should be avoided. One can easily meet their needs with good quality grass/alfalfa mix hay, a lower sugar/starch commercial ration formulated specifically for the young, growing horse, or if they are very easy keepers, oats work as long as the alfalfa is at least 1/2 of the hay in the diet. A vitamin and mineral supplement can also be added if necessary.


Answer provided by Carey Williams, Ph.D., Rutgers Cooperative Extension.




The material provided on this site is for educational purposes only and is not intended to diagnose, prevent, or treat any illness. Any recommendations are not intended to replace the advice of your veterinarian. Any products mentioned are not intended to diagnose, treat, cure, or prevent disease. Mention or display of a trademark, proprietary product, or firm in text or figures does not constitute an endorsement by the Equine Science Center or Rutgers University and does not imply approval to the exclusion of other suitable products or firms.







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