Pasture, for the Insulin Resistant Horse?

By Juliet M. Getty, Ph.D.

 

When is pasture safer for the insulin resistant (IR) horse – late afternoon or early morning? Google this question, ask your vet, or talk to a friend and you will get both answers!  How frustrating! It’s time we cleared this up.

Grass is a living organism and requires NSC (non-structural carbohydrates) for energy in order to grow. NSC is a measure of sugars, starch, and fructans and is produced through the process of photosynthesis when the plant is exposed to sunlight.

In general, the following are true: 

  • Grasses accumulate NSC as the day progresses, making them highly concentrated in NSC by the late afternoon.
  • Once the sun sets, grasses will metabolize NSC for energy, making them lowest in concentration in the early morning hours.

This pattern can be disrupted if the night temperatures remain below 40 degrees F (4 degrees C). When exposed to cold, grasses will hold on to NSC and not relinquish it during the night, making morning grazing less safe for the IR horse.

Other factors that increase NSC:

  • Stressors, such as overgrazing, drought, and too much rain
  • Mowing too short – limit mowing height to no less than 5 inches
  • Letting grasses go to seed
  • Fertilization stimulates growth

 

Warm season vs cool season grasses

Warm and cool season grasses behave differently during prolonged intense heat and sunlight[i]. Warm-season grasses (e.g., Coastal Bermuda and Teff) will naturally thrive during very hot, sunny days and accumulate substantial amounts of NSC by day’s end. However, cool-season grasses (e.g., timothy, brome, orchard, crested wheat grass, rye, fescue, as well as alfalfa) will actually be lower in NSC during periods of prolonged heat and sunlight, as long as the grass is adequately watered. This apparent contradiction occurs because heat and light stimulate the cool season plant’s enzymes that burn off NSC.

 

What about cloudy days? 

Here again, there is a difference between warm and cool season grasses. Photosynthesis still takes place during cloudy days. However, clouds usually cool down the temperature. This can potentially decrease NSC in warm weather grasses, but cool season grasses respond to cooler, more moderate temperatures with a higher NSC content.

 

It is a bit of an art form

You have to know your grasses. You can’t be passive about it. The best way to think about the NSC content in your pasture is to first know the type grass you have, which will give you an idea of what climates it prefers. Then, examine the amount of stress the grass is enduring. Stress will cause all grasses to be higher in NSC.

 

The best approach is to test your pasture

 It’s true that testing only provides a snapshot since grasses are living organisms and change from day to day. But you can get a good idea of how your grass is performing by testing early and late in the season.[ii]When testing your pasture:

  • Note the weather conditions on the day before you test
  • Choose a sunny day to take your samples
  • Take an early morning sample and a late afternoon sample and note the weather conditions

 

Interpreting the test results

 There are three measurements to consider:

1)      ESC (ethanol soluble carbohydrates): simple sugars

2)      WSC (water soluble carbohydrates): simple sugars plus fructans (long chains of fructose molecules)

3)      Starch: long chains of glucose molecules

Add ESC + Starch. You want this sum to be less than 11% (on a dry matter basis) to be considered safe for the IR horse. This is because ESC and starch digestion will raise blood glucose and cause a rise in insulin secretion from the pancreas. Elevated blood insulin is the basis for many laminitis cases.

NSC = WSC + Starch. If this number exceeds 13% (on a dry matter basis) and the ESC + Starch sum is below 11%, it tells you that the fructan level is elevated. Fructans do not significantly raise blood insulin and are generally not a concern. However, excessive fructan intake can possibly lead to cecal acidosis and endotoxin-related laminitis as a result of bacterial fermentation in the hindgut.[iii] There is a need for further, in-depth study since a dangerous level has not been established and studies using fructans have inconsistent results.[iv]

Fructans and starches vary according to the type of grasses. Cool season grasses and alfalfa tend to be higher in fructans, while warm season grasses accumulate starch. The sugar content of all grasses, however, can vary dramatically mainly based on environmental factors.

 

Bottom line

Pasture grazing is the best way to keep your horse healthy. Grasses are not only highly nutritious, but grazing supports both physical and mental health. Get to know your grasses and periodically have them analyzed to offer your horses grazing opportunities at the most opportune times and conditions.

 

This article updates and expands information in one of Dr. Getty’s previous Tips of the Month. Permission to reprint this article is granted, provided attribution is given to Juliet M. Getty, Ph.D. No editorial changes may be made without her permission. Dr. Getty appreciates being notified of any publication.

 

Juliet M. Getty, Ph.D. is an independent equine nutritionist with a wide U.S. and international following. Her research-based approach optimizes equine health by aligning physiology and instincts with correct feeding and nutrition practices. Dr. Getty’s goal is to empower the horseperson with the confidence and knowledge to provide the best nutrition for his or her horse’s needs.

 

Dr. Getty’s fundamental resource book, Feed Your Horse Like a Horse, is now in paperback as well as in hardcover, searchable CD and Kindle versions. All except the Kindle version are available at www.GettyEquineNutrition.com — buy the book there and have it inscribed by the author. Print and Kindle versions are also available at Amazon (www.Amazon.com); find print versions at other online retail bookstores. The seven individual volumes in Dr. Getty’s topic-centered “Spotlight on Equine Nutrition”series are available with special package pricing at her website, and also at Amazon in print and Kindle versions. Dr. Getty’s books make ideal gifts for equestrians!

 

Find a world of useful information for the horseperson at www.GettyEquineNutrition.com: Sign up for Dr. Getty’s informative, free e-newsletter, Forage for Thought; browse her library of reference articles; search her nutrition forum archives; and purchase recordings of her educational teleseminars. Find top-quality supplements, feeders, and other equine-related items, at her online Free Shipping Supplement Store[v]. Reach Dr. Getty directly at gettyequinenutrition@gmail.com.

 

 

[i] Watts, K., 2008. The influence of solar radiation and temperature on the diurnal fluctuation of NSC in grass. Rocky Mountain Research & Consulting, Inc. www.safergrass.org

[ii] Equi-Analytical Labs offers instructions on how to test your pasture. www.equi-analytical.com

[iii] Johnson, R.J., Rivard, C., Lanaspa, M.A., Otabachian-Smith, S., et. al., 2013. Fructokinase, fructans, intestinal permeability, and metabolic syndrome: An equine connection? Journal of Equine Veterinary Science, 33(2), 120-126.

[iv] Crawford, C., Sepulveda, M.F., Elliott, J., Harris, P.A., and Bailey, S.R., 2017. Dietary fructan carbohydrate increases amine production in the equine large intestine: Implications for pasture-associated laminitis. Journal of Animal Science, 85, 2949-2958.

[v] http://horsesupplements.gettyequinenutrition.biz

 

Myth: A Shiny Horse is a Healthy Horse

By Juliet M. Getty, Ph.D.

 

Fat from any source will make your horse shiny. A fatty substance called sebum, secreted from the sebaceous glands in your horse’s skin, increases when the diet is higher in fat. It coats the hair, making it reflect the sun’s rays. Any fat will do; the type of dietary fat doesn’t matter when it comes to making the hair coat shine. But it sure does matter when it comes to your horse’s health.

 

The converse is true – A healthy horse is a shiny horse…

As long as he’s shiny for the right reason – because you are feeding the right type of fat! With so many feeds and supplements available, where do you start?

 

Start with what comes naturally

Fresh grass contains 2-3% unsaturated fat consisting of a variety of fatty acids that vary in their chemical profile. There are two specific essential fatty acids that the horse’s body cannot produce and therefore must be in his diet: The omega 3 known as alpha linolenic acid (ALA), and the omega 6 known as linoleic acid. Grasses contain both of these in a 4:1 ratio of ALA to linoleic acid.

Most commercially prepared horse diets, however, have an inverted ratio of these two fatty acids because high linoleic acid fat sources such as soybean and corn oils are added to boost the fat concentration. When the omega 6 content exceeds the omega 3 content, you are asking for trouble.

 

Linoleic acid leads to inflammation

While some linoleic acid is important, too much can exacerbate your horse’s inflammatory response. Horses who are in training, working, or performing produce inflammation in their joints and muscles that can worsen when high amounts of linoleic acid are present. The aging joints of older horses are more painful when this omega 6 fatty acid is fed in large amounts. And inflammation leads to oxidative stress, which can damage all tissues throughout the body.[i]

 

ALA reduces inflammation

 Omega 3s block the formation of inflammatory molecules that are readily formed from omega 6s. Take a close look at the fat sources you are feeding to confirm that enough omega 3s are in the diet.  Read the ingredients and note the concentrations. Manufacturers of products that are high in soybean oil, for example, will often tout that the product contains omega 3s. This is true, but misleading. Soybean oil does contain about 7% omega 3s. But what they don’t tell you is that 50% of the fatty acids in soybean oil are from linoleic acid (omega 6).

 

The table below provides a better understanding of oils and oily feeds:

 

 

Approximate Fatty Acid Percentage in Oils and Oily Feeds

 

Oils and oily portion of feeds Saturated  Monounsaturated (Omega 9)[ii] Linoleic Acid (Omega 6) Alpha Linolenic Acid (Omega 3)[iii]

 

Camelina oil 13 19 16 38
Canola oil 7 54 30 7
Chia Seeds 10 7 19 55
Coconut oil[iv] 91             6 3 0
Corn oil 17 24 59 0
Flaxseeds  9 19 14 58
Hempseed oil[v] 10 12 55 18
Olive oil 16 75 8 1
Rice bran 17 48 35 1
Sunflower seeds 12 16 71 1
Soybean oil 15 26 50 7
Wheat germ 18 25 50 5

 

Hay has virtually no fatty acid content

Once fresh grass is cut, dried and stored, the naturally occurring unsaturated fatty acids are destroyed by oxygen. If hay is the predominant forage source for your horse, it is critical that you add a fat source that offers more omega 3s than omega 6s. Ground flaxseed or chia seeds are best for omega 3s. When supplementing, limit the amount fed to no more than ½ cup ground flaxseed or ¼ cup chia per 400 lbs of body weight (120 ml per 180 kg of body weight). The dosage for flaxseed oil should be 1.5 tablespoons per 400 lbs of body weight (22.5 ml per 180 kg body weight).

 

Not all equines are the same

Equines such as ponies, minis, donkeys, and mules cannot tolerate as much fat as horses. They require some fat, but generally 1/3 to 1/2 the amount given to horses, proportionate to their weight.

 

Bottom line

Read the ingredient label on any feed or supplement designed to add more fat to your horse’s diet. The ingredients may be imbalanced. While it will make your horse shine, it may do nothing to contribute to overall health and worse, it may actually increase inflammation.

 

 

Juliet M. Getty, Ph.D. is an independent equine nutritionist with a wide U.S. and international following. Her research-based approach optimizes equine health by aligning physiology and instincts with correct feeding and nutrition practices. Dr. Getty’s goal is to empower the horseperson with the confidence and knowledge to provide the best nutrition for his or her horse’s needs.

 

Dr. Getty’s fundamental resource book, Feed Your Horse Like a Horse, is now in paperback as well as in hardcover, searchable CD and Kindle versions. All except the Kindle version are available at www.GettyEquineNutrition.com— buy the book there and have it inscribed by the author. Print and Kindle versions are also available at Amazon (www.Amazon.com); find print versions at other online retail bookstores. The seven individual volumes in Dr. Getty’s topic-centered “Spotlight on Equine Nutrition” series are available with special package pricing at her website, and also at Amazon in print and Kindle versions. Dr. Getty’s books make ideal gifts for equestrians!

 

Find a world of useful information for the horseperson at www.GettyEquineNutrition.com: Sign up for Dr. Getty’s informative, free e-newsletter, Forage for Thought; browse her library of reference articles; search her nutrition forum archives; and purchase recordings of her educational teleseminars. Find top-quality supplements, feeders, and other equine-related items, at her online Free Shipping Supplement Store[vi]. Reach Dr. Getty directly at gettyequinenutrition@gmail.com.

 

[i] There is another omega 6 that is not as prevalent in the horse’s diet, known as gamma linolenic acid (GLA). GLA is receiving attention for horses’ diets because unlike linoleic acid, GLA actually reduces inflammation. GLA is found in significant quantities in hempseed oil (see note v below), and is also found in evening primrose oil and spirulina.

[ii] Omega 9s are another classification of fatty acids that do not promote inflammation and may protect the heart and blood vessels.

[iii] Fish oils are also high in omega 3s. However, ALA from plants is converted to the longer chain omega 3s found in fish oils.

[iv] Coconut oil is popular, but it has no omega 3s. Therefore, if you feed this as your only source of fat, your horse will become deficient in this essential fatty acid. He’ll be very shiny, but he will be unhealthy. Coconut oil is more than 90% saturated, with a smidgen of linoleic acid. The saturated fatty acids exist mostly as medium chain triglycerides (MCT), which is controversial because these types of fatty acids do not exist in grasses. However, MCT are metabolized differently from saturated fats and may be beneficial for metabolically challenged horses.

[v] Hempseed oil also contain approximately 2-4% Gamma Linolenic Acid, a beneficial omega 6 fatty acid known to reduce inflammation.

[vi] http://horsesupplements.gettyequinenutrition.biz

 

 

Permission to reprint this article is granted, provided attribution is given to Juliet M. Getty, Ph.D. No editorial changes may be made without her permission. Dr. Getty appreciates being notified of any publication.

 

Broodmare Nutrition During Late Gestation

Broodmare Nutrition During Late Gestation

With a rapidly growing unborn foal, the transition time from mid- to late-gestation can pose nutritional challenges for pregnant mares.

 

Shoreview, Minn. [February 24, 2017] – Up to 60 percent of an unborn foal’s growth happens during the last three months of pregnancy. As such, late gestation can pose nutritional challenges for pregnant mares.

Comparatively, unborn foals grow very slowly (approximately 0.2 pounds per day) during the first seven to eight months of gestation, causing very little nutritional stress on the mare.

“Dry mares in early gestation can be fed like a mature, idle horse,” says Karen Davison, Ph.D., Director and Nutritionist for Equine Technical Solutions at Purina Animal Nutrition. “Good quality pasture or hay along with a ration balancer or vitamin/mineral supplement may be all that is necessary to meet the mare’s nutritional requirements.”
However, during the last 90 days of pregnancy, the fetus gains approximately 1 pound per day and has a significant impact on the mare’s nutritional requirements for protein, vitamins and minerals.

Additionally, the increased size of the fetus takes up more room in the mare’s body cavity, which may result in the mare eating less hay or forage. This reduction in forage intake, coupled with increased nutritional demands of the pregnancy, requires mares to be supplemented with a nutritionally-balanced feed ration to meet total nutrient requirements.

“Even in situations where forage alone is maintaining mares in acceptable body condition, it is important they receive quality concentrate supplementation,” advises Davison. “While good quality forage may be able to provide sufficient calories to maintain body condition of the mare, other nutrients such as protein, vitamins and minerals, will be deficient.”

Proteins

Research has shown foal birth weight can be negatively affected when mares are not fed adequate protein during late gestation, even when mares are maintained in fleshy condition.

“It is not uncommon to see fat mares have small, weak foals when the mares’ diets are adequate in calories but low in quality protein sources,” says Davison. “Even when mares are fed high-protein forage, such as alfalfa, the diet can still be deficient in important amino acids.”

Davison suggests supplementing mares in late gestation with a feed ration containing quality protein sources to help meet amino acid requirements for optimal foal development.
Minerals

During the tenth month of gestation, the greatest amount of mineral retention occurs in the unborn foal. Adequate trace mineral supplementation for the mare is critical for normal fetal development and provides sufficient minerals for the developing foal to store and utilize immediately after birth.

“In the first weeks of life, foals will not eat sufficient amounts of fortified feeds and may not have adequate absorption of dietary trace mineral sources at this early stage of development,” says Davison. “Proper mineral nutrition of the mare in late gestation helps ensure the foal receives an adequate supply of these important nutrients to use during very early growth stages.”
Thin mares

It is important to properly support good body condition through late gestation to ensure the mare is in good shape at foaling.

“When mares are thin with ribs showing during late gestation, it’s an indication the mare isn’t meeting her own calorie requirements for maintenance. As such, it’s likely the growing foal inside isn’t receiving adequate calorie nutrition for proper development,” says Davison. “The day the mare foals, her calorie requirements increase dramatically. If the mare is thin when she foals, her milk production and the early development of the foal could be negatively affected.”

In these cases, Davison advises feeding a calorically- and nutrient-dense feedto supply the needed energy and weight gain without feeding excessive amounts of grain.

 

Fat mares
If a mare is significantly overweight during late gestation, where ribs cannot be seen and are difficult to feel, Davison says it is important to provide adequate protein, vitamins and minerals to support optimal fetal development without adding unnecessary calories.

For overweight mares, Davison suggests a concentrated protein, vitamin and mineral supplement designed to be fed at 1 to 2 pounds per day. This type of supplement or ration balancer will meet the nutrient needs of the unborn foal without causing weight gain in the mare. It may be necessary to restrict hay intake to 1.5 percent of the mare’s body weight if she is significantly overweight.
Proper nutritional management of the broodmare during late gestation will give her foal the best start in life. With the time and money invested in getting a foal on the ground, it’s important not to skimp on mare nutrition during this critical time.

 

For more information on broodmare and foal nutrition, visitwww.purinamills.com/horse-feed.