PNER Convention Notes – "10 Things You Can Do Better" by Susan Garlinghouse, DVM, MS

First in my convention-note lineup is a talk given by Dr. Susan Garlinghouse. She is fairly well known in the endurance world for her articles on equine nutrition and other salient topics regarding the health and fitness of our horses.

During this talk she essentially rounded up some of the more interesting things she had found from scientific research, and the practical applications of this recent research. Everything she talked about comes from her reading peer-reviewed research journals (so we don't have to?).

There were several points that are very applicable to Deli and I. I hope making my notes available will be helpful for other riders and horse lovers.

1. How to Feed Feet

There are tons of factors go into growing a good foot – bio-mechanics, genetics, age, breed, metabolic rate, temperature, and moisture (so the season and climate in general matter quite a bit for what a foot needs). Nutrition is a big deal but there is no one thing that is a silver bullet.

The key points from the nutrition standpoint are:

• Feed enough calories – the quality of their feed might not be high enough. In a positive energy balance they will grow foot 50% faster than horses on a restricted diet (not meaning the horse is on a “diet” for weight control, jut that the horse might be working more than the calorie intake received).
• Provide a good amino acid profile – don’t just supplement one amino acid and expect it to make a difference (for example, don’t just add methionine).
• Should you add minerals? If the mineral profile is already adequate, adding more is not going to help (and it might hurt). What’s more important that adding in single minerals is BALANCE. Don’t add a specific mineral unless you have a shown deficiency.
• Chelation of minerals is when bonded mineral to some kind of protein. This kind of mineral may increase rate of hoof growth. Minerals are absorbed more easily when chelated but it’s going to cost more money. Look for things like “zinc proteinate” or some kind of yeast. Zinc is a good one to be chelated.
•  Gelatin does not help – it has no scientific influence on hoof growth (And it’s not good for your fingernails either).
• Adding fat to the diet – adding a generic supplement will not help hoof, but it could help keeping the positive energy balance discussed earlier. However, adding fats high in omega-3 fatty acids IS beneficial for the foot.  This WILL provide direct benefits to their coats and hoof. Essentially these kinds of fats will add increased tensile strength if fed in the right amounts for long enough.
• Premium commercial feds provide a good vitamin-mineral balance if feeding around 5lbs a day. More cost effective than multiple supplements! For example: LMF Gold.

2. Feeding Biotin (for hoof quality) – it does work!

As for specific supplementation, Susan Garlinghouse discussed biotin extensively (which makes sense – it’s a common additive to hoof supplements). Biotin is one of the more expensive vitamin supplements. Most supplements do not add a lot of this because it’s expensive. The daily requirement for biotin is around 1-2mg/day just for general health. But if you supplement extra (15-20mg/day) you are going to get better hoof quality with some patience...

It will take 6 months to appreciate the difference with the 15-20mg/day dose. In about 9 months you should see a statistical difference (most horses grow out a foot in this timeline). In 33 months you see the increased tensile strength in the foot.

So yes, biotin can help a great deal with “feeding a good foot” if you keep in mind these baselines:

• Be patient and consistent!
• Improved quality: 5-7.5mg/day. At 15-20mg/day you see even better quality but no increased growth. At 50mg/day – you will see increased hoof growth. This will be around 15% better growth, plus a higher quality of hoof.
• Not every horse is going to respond, however. There are other factors that contribute to the hooves growth and strength (you need to have an overall good environment and supplementation before you can get payback).
• Biotin is a B vitamin (B7) and is not stored in the body – you have to feed supplement 2x a day if you are giving 50mg/day otherwise it will just be “an expensive pee puddle”.
• Her personal favorite is Paragon Biotin Plus – one scoop is 50mg. It also includes yucca. Yucca in naturally-occurring feed supplement is okay (otherwise it’s on AERC’s prohibited list).
• I personally recommend HorseTech’s Bioflax20 product. I didn’t know horses should be getting at least 20mg/day of biotin – but looking at the dosages for this product the horse does get the 20mg in the normal dose! The company also has higher doses in other products.

3. Feeding Fat

This topic is one I’ve seen discussed a lot within the endurance community. So, why feed fat? It has 2x the calories that protein and carbohydrates do, and it’s highly digestible! So feeding fat makes it easy to maintain a horse’s body weight.

The vegetable fats are more digestible (about 90%) and animal fats  are somewhat less  digestible (about 75%) because they have an added mineral content. In contrast, forage on average is 50-60% digested. What is not digested is poop, urine, or heat. You need that also, but heat is also a byproduct of exercise. A horse gets very hot during exercise and when their normal cooling process aren’t operating, they can get to a lethal core temperature in <15 minutes.

Feeding fats DECREASES the thermal load! Thermal load is higher in: larger horses, carrying heavier weight, heavily muscled horses. (This will tie into competing the non-Arab in endurance because one of the primary advantages Arabs have is a lower thermal load.)

Fat in the diet also provides glycogen-sparing effect. Glycogen is animal storage form of starch. Glycogen is a big bushy molecule. It’s not efficiently stored compared to adipose tissues so is in very limited supply. This means that feeding fat makes the animal more fuel efficient and Improves glycogen utilization. Once a horse had adapted to a high fat diet (which takes 5-10 weeks) they can still replenish glycogen repletion. High carbs are not something you want to feed a tired horse, so getting horses fat-adapted makes their rebound easier after a tough ride as well.

Fat is a SAFER feed than a lot of grain! Horses get more fuel efficient when exercising using aerobic metabolism processes and when they are used to burning fat, this process is encouraged over anaerobic energy uses. The glycogen sparing effect is also associated with a decrease in respiratory exchange ratio.

The comparison of oxygen consumption to CO2 produced does relate to the glycemic cycle in a horse as well. Adding dietary fats smooth’s out the glycemic/insulin curves from starchy meals, so your horse will have less of an energy rocket-boost and then a corresponding crash. Ideally its better to have sustained energy. Another reason to avoid large swings in the glycemic index is that insulin suppresses the horse’s ability to oxidize fatty acids – and you want them to be oxidizing fatty acids. All of this ties into how you want to feed a horse before a ride: ideally you want to SMOOTH OUT the glycemic/insulin curves.

Other considerations of a high-fat diet in the endurance horse include:

• Horses on high fat also digest grain better.
• One thing to note that is perhaps a bit unexpected: horses on generic HIGH fat diet show symptoms of being insulin resistant! However, if you change their diet to include 1-2oz of marine oil daily abolishes IR effect. So with a high fat diet add a little fish oil and add that. Dr. Garlinghouse recommended the product “EO3”, which is a marine oil source.
• Don’t ever syringe straight oil down the throat as it does not induce the “swallowing” effect and they can easily aspirate it into their lungs.
• What about the adage that you should stop feeding fat a couple days before an endurance ride? Essentially, fat consumption makes the horse less hungry. You want the horse to be stuffing itself with FORAGE before and during the ride-day as it is the best thing for gut health and water absorption. During the ride you should not add additional fat to their meals. You want your horses hungry whenever you make hay available to them. A horse can’t utilize fat on ride-day anyway. Edit to add another comment from Dr. Garlinghouse: "It's okay to feed a ration that happens to contain significant fats, and it's okay to add a high fat feed, like rice bran, as a flavoring agent. Just don't add a specific fat source, like pouring corn oil on their mash. I generally stop adding additional fats a day or so before a ride." 
• What about coconut oil? One of the fatty acids in coconut oil is lauric acid – the only other place it’s found is in breast milk. Lauric acid has been linked in some research with cancer fighting properties. But before you get too excited, this is what the actual research said about lauric acid and cancer: one of the metabolic byproducts of it, when put into a lab petri dish the “cancer did not like it.” Does this mean it actually has cancer-fighting properties? No! Essentially just think of coconut as fat a fat source. (It also tastes good and is therefore a palatable fat if your horse is picky.)

4. Chia seed vs. Flax?

These two seed sources are commonly fed to our equine partners and in her talk Dr. Garlinghouse compared them. Actually, she mostly talked about the benefits of feeding flax.

These seeds have equivalent omega-3 content but Chia is twice as expensive (so why buy it?). Flax helps with hoof and hair quality and helps as an anti-inflammatory. It’s good for arthritis and it’s great for horses in the endurance sport because endurance creates a certain amount of inflammation in joints and tendons even if it's not a chronic condition.

So what are the research points for flaxseed in a horse's diet?

• Every horse should be getting omega-3 fatty acids.
• Some endurance horses who had metabolic issues did well on 4-5lbs of flax a day (suggesting it's pretty safe for horses with metabolic issues).
• Lingan is higher in flax than in chia – lingan is a phytochemical structure (ie. An insoluble fiber which just providing bulk).  It does have a weak estrogen-like properties but the Dr.  Garlinghouse assured us that that is near impossible to actually make a measurable difference. She told us a story about a bunch of stallions on a rigorous breeding schedule who needed a lot of calories and were getting 5lbs of ground flax a day without experiencing any fertility issues. Though it has not been tested in horses, lingan can be protective in humans (prostate and breast cancer!).
• Human grade flax seed is okay to feed to our horses. Golden and brown flax is the same.
• Don’t over-grind the flax. You degrade the omega-3 if you grind it too much (because it gets too hot). Also, getting it pre-ground is risky. As long as it’s not rancid it will still provide some fat content to the horse, but the omega-3s degrade more quickly. Feed within 10 days/2 weeks. Put it into freezer bags to make it last longer.
• Flax does have the cyanide precursors that in some bodies do turn into cyanide. But the dose makes the toxin! It is another “cowboy myth” that flax seed is toxic because of these cyanide precursors. How did the myth start? It began– from cows fed linseed cake (which is the same plant but with the oil taken out of it). Cattle have the enzyme to break down the cryogenic precursors and they had some issues arise. Horses do not have this enzyme! Or at least not in high concentrations.

So how much should you feed?

• For flax: give a cup to 2 cups a day (start at ½ a cup a day or you will get diarrhea) for a horse doing LD or 50s. It’s more palatable than a lot of the oils.
• What about flaxseed oil? Plain flax seed is 20-25% fat and is a lot less expensive. The oil is harder to keep fresh – it’s very sensitive to light, and needs to be refrigerated.
• What about grinding flax? You will get 2x the digestibility out of ground (slightly ground). This is different than oats (where grinding does nothing) because flax is a SEED and has a hard hull.

Someone asked about black oil sunflower seeds. For BOSS – good way to get fat into them as a source of calories. But they have more omega-6s than omega-3s (and omega-6s are pro-inflamation). But at a better ratio than most vegetable oils!

5. Feeding Grain to the Endurance Horse

Oats, corn, barley, etc. The main thing to remember about feeding grain is: there is a limit to how much grain horses can digest in a day.

When feeding 5-11lbs of grain a day the risk of colic increases by a significant percentage. Why? Starch meals are digested by enzymes in the small intestine. It is like a conveyor belt and just keeps moving when healthy. When there is too much grain it gets dumped into the cecum. The cecum will treat it like forage because that's what the cecum does!

When grain gets to the cecum it makes the environment acidic ( which is called "cecal acidosis"). This condition associated w/ colic, laminitus, endotoxemia, EGUS, and other things you want to avoid in your equine partner. What's more, ulcer medication does not heal ulcers in the hind gut, so you should avoid ulcers as best you can. Dr. Garlinghouse noted that horses with fore gut ulcers often have diagnosed hind gut ulcers.

Other considerations for feeding grain include:

• Feeding 10lbs of grain a day also decreases fiber digestion.
• Sub-acute cecal acidosis contributes to decreased appetite.
• Digestibility NOT improved by splitting a large amounts of grain into many meals.
• The least digestible grains are corn and others with a very hard casing (the “hard grinds”). There is NO advantage to processing oats or other grain feeds compared to the straight grain (crimping, rolling, etc.). 
• Commercial feeds do things to grain to make them more digestible, so if you want to feed grain that might be the way to go.
• With respect to sprouting grains (as in fodder): it does improve digestibility, improves the vitamins the horse can access, and makes it palatable. If the grain is still intact enough to sprout and grow then you know you are getting a high quality grain. 

6. Ride-day Breakfast

• Re-think 4am grain or concentrate breakfast. Why not? Because you don’t need the energy spurt at the start of the ride. You want the burst later and you don’t want a slump at the “lunch” hour. This does not mean they can't get a mash of soaked pellets or something similar. So give them a flake of alfalfa in the morning. Or soak some pellets of alfalfa. Just to make him happy!
• The horse should be eating FREE CHOICE forage all day long! And days beforehand. This packs the gut full and will help store water if nothing else.
• Feed them any concentrates the DAY BEFORE (before midnight). The "lighter fluid" can be filled up the day before and your horse's glycogen stores will be full. And you will skip the glucose-insulin curve with this practice.
• Make sure he finishes all concentrates before midnight the night before.
• The only horses that need carbs during the day are the ones being competitive. 

7. Preferred Gait Studies

How does the body mass and distribution of weight affect energy costs? Does reducing mass of a distal limb increase energy efficiency? 

We know there is a linear relation between increasing mass and energy costs. When measured in fit Arab horses, adding 1.5lbs to each ankle increased energy costs by 11%. If the same amount of weight was at the center of gravity increased energy costs by only 0.6%. So every 1lb you add to the legs equals the same energy cost (approximately) as adding 18lbs over the center of gravity (such as tied to the saddle or breast collar). But you don’t get the extra “credit” points when standing for best condition if you have things on your horse's lower limbs.

So what should you do? Essentially, balance hoof protection against unnecessary additional weight! Ask: does my horse really need splint or bell boots? Does he need the heavy shoe or can I find something lighter? Or maybe be dynamic and change the booting and leg protection throughout the ride. For example, if you know the first loop is going to have a lot of brambles or cacti, put on protective boots and then pull them off for the second loop which has more sandy terrain.

(This is one reason it's important to train in the gear you are going to use, too, so your horse get's used to the energy expenditure required in wearing boots.) 

8. The "Sweet Spot" for Gait

Energy costs for the horse rise outside the “sweet spot” – ie. the speeds they are willing to keep up all day long. Most horses will have this for each gait. If the horse chooses their own speed they will usually choose the sweet spot themselves. Where an extended (or collected) gait goes away from the sweet spot we should make them transition to a different gait or else they are expending energy needlessly. The main qualifier for this is that if you have an inexperienced horse they may try and tell you their "sweet spot" isn’t quite what it actually is (I promise, Deli, the sweet spot is not jigging sideways). It's always good to change gears every now and then to use different muscle groups, anyway.

This is another area heart-rate monitors can be very useful. With a heart rate monitor you can tell his "sweet spot" is – that’s where his heart rate will be the lowest at that particular gait. As your horse gets more experienced that sweet spot is going to change. It usually gets faster as a horse gets more fit mentally and physically.

I am really curious to figure out Deli's "sweet spot". She can trot like a demon sometimes (approximately 14mph) but she seems most efficient at 7mph or so. Her walk varies widely, usually slower at the start (2mph) and warming up to 3-3.5mph. Not a fast walker!

9. Joint Supplements

The only joint supplement that is supported by data is Cosaquin. And yet even cosaquin is only about 3-4% bio-available to the horse. Glucosamine and the different sulfite joint supplements are not bioavailble to the horse when ingested. Why? The size of the molecule matters and can't be utilized well by the equine.

Adequan (or Legend) works better because you are bypassing the digestive tract. Adequan is 90% more bio-available. So Dr. Garlinghouse's recommendation is that you get 2 vials of Adequan rather than buying expensive supplements. In the long run this might actually save you money!

Here is another article I found comparing Adequan, Legend, and Pentosan. I'm particularly interested in researching and asking my vet about Pentosan for Deli, as she doesn't have any specific joints that are problematic (just a history of traumatic injury).

10. The best thing to feed DURING the ride is hay! 

You can also feed a lower-glycemic mash (triple crown senior is pretty good for this). As an aside – green grass is MAGIC for horses! If you have access to pasture and your horse is not sugar sensitive, green grass can do wonders to multiple systems in a horse’s body. This includes ride-day.

This is what we do at the end of anything long: a good roll!

That's all for now! Since a lot of what Susan Garlinghouse spoke about related to nutrition, I thought I’d provide a link to an article on nutrition and management made specifically for Green Beans.

Last time: The 2016 PNER Conference was a blast!

Next time: Notes from "Endurance Foot Care" by Sue Summers and Lee Pearce.