Nutrition for endurance horses – PART 2

As a continuation of my notes taken at Dr. Steve Duren’s talk on feeding endurance horses properly at the January 2014 PNER annual conference. If you missed it, check out PART 1 of this discussion for more information of feeding an endurance horse during and after an endurance ride.

This later part of the talk dealt mainly with other niceties beyond what to feed during and after an endurance ride. In other words: what about the fiddly supplementation you can do with horses? Why do it, and what substances matter and why?

Other Supplementation in Endurance Horse Diets

There was some discussion about other supplements that are commonly fed to endurance horses, which was great to hear because some of these issues apply to Deli and I now even though we are just starting back into riding more vigorously!

Magnesium (Mg) is commonly fed because it helps muscle and nerve function. I actually feed Deli magnesium and chromium to help curb her anxiety (and yes, it helps). What I didn’t know is that feeding too much Mg can inhibit calcium absorption because Ca and Mg are absorbed through the same pathways. And yes, endurance horses do need that calcium (see discussion below). Dr. Steve Duran’s recommendation was to feed no more than 25g of magnesium daily to avoid issues with Ca absorption.

Calcium (Ca) supplementation can be helpful because calcium functions in muscle contractions. An easy way to get some more Ca in an endurance horse’s diet is to add a little alfalfa. Beet pulp is also higher in Ca than grass hays.

Beet pulp is a common feed in the world of endurance, and Dr. Duren had some things to say about it as  a forage source. In this discussion it was acknowledged that beet pulp is essentially a super fiber – it is 80% digestible compared to hay, which is normally around 50% digestible. In my nutrition classes in college beet pulp was always referred to as a soluble fiber for this reason. As far as this expert was concerned, it was a safe forage feed but without a lot of its own nutritive value beyond that it as a digestible fiber. Oh, and it really is a myth that if a horse eats un-soaked beet pulp it will swell and explode in their stomachs. You won’t believe how many boarding barns I have been at where the barn manager was under the impression beet pulp would lead to horses exploding left and right, so it as nice to hear this myth stomped on yet again by an expert.

Selenium (Se) is a mineral that is deficient in many Oregon soils where hay is grown, and so I supplement Deli with it as a matter of course. Both selenium and vitamin E are also antioxidants that help prevent the condition of tying up, so these minerals are a good thing to add to an endurance horse’s diet beyond the fact that they might not be getting what they need from the hay they are eating.

That's all for endurance horse nutrition! Next up will be my notes on lameness in endurance athletes at the ride, which includes some discussion on the function of endurance vets and what exactly they are looking for in those trot outs. It was a great panel for the endurance green bean in me to hear the vet talk about ride vet checks, and I hope my notes in the topic will be helpful for others as well.

Nutrition for endurance horses – PART 1

The Pacific Northwest Endurance Rides Convention was located in Portland this January, so of course I had to attend. It was an absolutely wonderful time – I went to many panels and talks, perused the trade show, and finally met quite a few of the Pacific Northwest endurance riders and endurance newbies (like myself) that I have interacted with online over the course of a couple years. Everyone in this community is so friendly and it seems that horse people that like to GEEK OUT about their horses are particularly attracted to this sport. Just another reason I think it is a good fit for me: I can talk about nutrition and hoof care and what have you for hours and be as happy as a clam. I’m a total geek.

It was great fun, and I like to think I made some new friends that I will see again soon either at rides in the region or at get-togethers that are now being arranged in light of the new “green-bean” groups that are popping up everywhere.

I still have yet to do a ride myself (though I do have PLANS, even if nebulous at this point), but I’m still finding myself addicted to this sport. I can’t get enough.

At several of the talks I attended I took copious notes, as is my way, and I thought it would be highly valuable to write up what I’d learned for this blog so that others could benefit that did not attend the conference, or who maybe are not as obsessive with their note-taking as I am, or who would like an easy reference. I think this information was particularly interesting to me because even though I HAVE a pretty thorough background in equine nutrition, hoof care, and biomechanics from studying equine science at UC Davis way back when, all these talks focuses on the specific requirements of the ENDURANCE HORSE. And of course it would be different.

One of the several talks I took extensive notes on was Dr. Steve Duren’s on Feeding Management After An Endurance Ride. And without further ado, what I learned:

Alfalfa vs. Grass Hay 

Throughout my life when it came to horses, this topic has always been hotly debated. In my equine nutrition classes at UC Davis alfalfa was often cited as being overfed to equines, and that it should be no more than 20% of the diet, not just because it has an inverted Calcium:Phosphorus ratio, but because it is very high in protein and calories compared to the needs of more horses. There was also some discussion that it could contribute to the formation of enteroliths in horses (particularly Arabians, at that). In California, many barns fed ONLY alfalfa hay, which was always a big no-no to me.

The nutrition expert, Dr. Steve Duren, agreed with these basic principles, but also noted that alfalfa, when fed at no more than 20% of the forage diet, can be very helpful for the endurance horse because: 

•   It has more calories than grass hay, and endurance athlete need and use those calories. And it’s better for them to get calories in a forage source like alfalfa hay, because horses are meant to eat forage, not grains and lots of starchy sugars.
•  It is a good bio-available protein source, which endurance athletes need to repair muscle.
• The excess calcium in alfalfa hay actually can help prevent ulcers because it acts as a buffer – and yes, this does mean that feeding some alfalfa hay PRIOR to exercise is a great idea (to help protect a horse’s stomach from acid splash).
• Otherwise, the nutrition expert said that the majority of a horse’s diet should ALWAYS be grass. Grass is what horses were made to eat, and the endurance athlete is no different in that respect.

Feeding Grains 

As far as feeding grain (like corn, barley, oats & rice) is concerned, the points of the discussion mostly settled on a couple concerns and things to know and put into practice:

• No more than 4lbs of grain should be fed per day – 1-2lbs per day is better if there is a need.
•  Grain should always be fed in as many feedings as possible.
• Grain should mostly be used to address a horse’s body condition (i.e. they are too thin and need more concentrated calories). 

Feeding Fat

Endurance horse should always have some fat in their diet (this comes from your oily foods) because the equine body needs to be taught to eat and digest fats well (so you shouldn’t dump fats as a new feed on them during or after an endurance race). Fatty foods also have the added benefit of slowing down how quickly food leaves a horse’s stomach, helping to prevent ulcers. 

Timing of Feeding 

This was one of the most valuable aspects of this talk, because how different feeds were digested and therefore utilized by the body. In other words: when do you feed WHAT before, during, and after, an endurance race?

• Feed “grain” (anything other than forage-type feeds) at least FOUR hours before a ride. This allows the horse to digest and store the energy in time for exertion.
•  Feeding grain right before a ride can cause problems because the energy isn’t available and they are spending energy and water digesting rather than that energy going to the muscles and the water being available to cool the horse (through sweat).
• “Grain” during a vet check won’t do any harm because you haven’t stopped exercising.
•  After a ride your goal should be to erase the nutrient deficit created during the ride (water, and energy in the form of calories).
•  If a gut is full of forage-type foods, it can hold and store more water. And yes, you WANT this. So free-choice forage foods (hay, beet pulp) are always good.

There was quite a bit of learning to be had with respect to post-ride feeding – this is complicated and fascinating stuff! Essentially, feeding an endurance horse for RECOVERY after a ride should be thought of in three phases, which are as follows:

PHASE 1 – within the 24 hour period after a ride.

This is when the horse is the most depleted and the equine’s metabolism is still revved up, the gut disrupted. The first thing to ensure is that you correct hydration – allow them to drink! If a horse isn’t drinking enough an IV may be needed to monitor their water intake more closely. If they aren’t drinking they can crash very quickly.

In this phase, horses should get whatever FORAGE they will eat. This means: free choice hay and grass, in whatever type they will eat. Forage also usually has a lot of potassium, which is an electrolyte. If they are eating forage their thirst process will be triggered.

Grain in the first 24 hour period should be fed to replace depleted muscle sugars and rebuild muscle glycogen stores (it is fueled up with ATP = stored sugar) so that the horse’s muscles will recover faster. As far as timing in this is concerned, it’s best to feed grain within 1 hour of finishing.

As far as feeding electrolytes POST-race, it was noted that eating and drinking should come well before supplementing with electrolytes.

PHASE 2 – two to three days post-race.

Hauling a horse has high energy requirements, so it’s important to take that into account as you head home. Forage should still be free-choice at this stage (I’m sensing a theme) and grain should come in smaller portions, more often. Probiotics are a good idea at this stage as well, to help get the equine machine working seamlessly again.

During this phase some low-key exercise is a good idea to keep everything moving towards the state the horse was in before the race. Assuming the horse was better before the race than they are afterward.

PHASE 3 – four to ten days post-race.

Horses may have rapid weight loss during this phase as they replenish their stores, but their soreness and tiredness should be less. At this stage, you guessed it, feed a lot of fibrous forage! Fiber is burned for energy in the presence of oxygen, which is what endurance horses need.

Deli prefers fresh grass over anything.

Fat should be fed in this stage in good quantities, though you should have been feeding fat all along.

Again, some easygoing exercise is going to help a horse recover more quickly going into this phase.

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I took copious notes on this topic because I am a serious NERD for equine nutrition in general. If someone gets me started talking at my barn the conversations usually ends with them slowly backing away from the flood of information spewing from my mouth. I think it surprises them because I really am a quiet and reserved person. Normally.

At any rate, stay tuned for PART 2 of feeding the endurance athlete!