Unusual Eating Behavior – Culprit Could be Salt Deficiency

Salt Block for HorsesUnusual eating behavior ( sometimes referred to as pica) can be caused by a number of factors and may cause the horse to eat manure, eat dirt, eat bark off trees, chew on board fences, chew on stable mate’s mane & tail or chew on tool handles or leather equipment.

I usually suggest going thru the following check list for the most common causes of unusual eating behavior:

  1. Lack of salt. Lack of salt can trigger a number of unusual eating behaviors (eating manure, chewing bark on trees, eating dirt, chewing on objects, chewing on tool handles etc.) Recommendation is to offer loose salt free choice as horses will consume more readily than block salt, particularly in cold weather. Block salt is better than not offering any salt source. Maintenance horses require 1-2 ounces of salt per day.  This may increase to 4-6 ounces per head per day in hot humid conditions or with added exercise.  Commercial feeds may contain 0.5% salt.  Horses may still benefit from salt being offered free choice along with access to fresh, clean water.
  2. Fiber intake in the diet might be inadequate. If a horse does not feel full, it will look for other things to eat. Make sure there is adequate long stem roughage available.  Fences, trees, manes and tails may suffer if there is not sufficient roughage!
  3. Phosphorus deficiency. Horses have quite limited “nutritional wisdom”, but phosphorus deficiency may trigger unusual eating behavior, including eating manure or dirt. Offering a free choice calcium, phosphorus and salt mineral may be useful.  In the wild, animals frequently consume bones or shed antlers to get minerals.
  4. Protein deficiency. Again, horses have limited “nutritional wisdom”, but inadequate protein or poor quality protein may trigger some of the unusual eating behaviors. Evaluating the forage and the overall feeding program is useful.
  5. Ulcers. Horses that have ulcers will sometimes eat dirt or manure as well as chew on other objects. The saliva produced when chewing is believed to have a buffering effect.

I always start by offering loose salt free choice and making certain that fiber intake is adequate. If that does not remedy the problem, I will then go to offering a good mineral product (calcium, phosphorus, salt combination, perhaps with some trace minerals) and perhaps a full ration evaluation.  Other behaviors may help decide if ulcer assessment is needed.

Unusual behavior may be the horse’s way of trying to tell us something!

Feeding and Managing Pregnant Mares: Prenatal Nutrition

Pregnant MareMany broodmares are in the last half of gestation at this time. The latter part of gestation is one of the most important development periods in the life of a foal when the foal is developing in the uterus of the mare.  The importance of this period was recognized in the Nutrient Requirements of Horses, Sixth Edition, when the Committee established that the nutrient requirements of the mare start increasing at the 6th month of gestation, earlier than previously believed.  During the last three months of gestation, the foal may be gaining an average of one pound per day.

The key elements of managing the pregnant mare are the following:

  • Maintain appropriate body condition score.
    • Mares should be at about a body condition score 6 when they foal so that they have sufficient energy reserves for early lactation as well as to maintain condition for re-breeding.
  • Adequate protein/amino acid intake.
    • Lysine, methionine, and threonine, the first 3 limiting essential amino acids, need to sufficient in the diet for placental and fetal development.
  • Adequate mineral and trace mineral intake.
    • The mare needs to be receiving adequate calcium, phosphorus, magnesium, copper, zinc, manganese and selenium to provide minerals for the development of the foal and to build the foals own trace mineral reserves.  Trace minerals are also critical for immune support.
  • Vaccinations and deworming.
    • A regular vaccination program should be developed in conjunction with a veterinarian so the mare is protected herself and can also produce the appropriate antibodies to protect the foal when it nurses and receives the colostrum that contains maternal antibodies.  This is what protects the foal until it can be vaccinated and develop its own antibodies.  The mare should also be dewormed as needed prior to foaling.

Good quality pasture or forage may provide sufficient energy thru late gestation, but may NOT provide adequate amino acids and minerals for optimal fetal development.  A well-designed ration balancer product may be used from month 5 to about month 10 or 11 of gestation to provide the missing nutrients.  A well-designed feed for broodmares and foals should be introduced prior to foaling so that the mare is on the feed before she foals to avoid the need for a sudden change in feed at foaling. This feed can then be increased after foaling to provide both the increased energy and the increased nutrients that are required for lactation, as well as providing nutrition for the foal when it starts to nibble on feed.  Fresh clean water and free choice salt should also be available at all times.

Feeding the broodmare properly can help reduce the risk of developmental problems for the foal and help insure that the mare can be rebred in a timely manner to produce another foal the following year if desired.

Cold Weather Care and Feeding of Horses

Horse in pasture during snow fall

Cold weather, particularly below freezing temperatures and cold rains, requires that owners pay careful attention to their horses to make certain that the horses maintain weight through the winter months.

First, make certain the horses are at least a body condition score of 5 or 6, meaning that the horses are carrying some fat cover over their ribs. Body condition should be monitored by physical examination at least monthly as long hair can hide weight loss. This is particularly important for older horses. The horses should also be kept up to date on dental care and overall health care, including appropriate deworming. It is a good idea to let horses go barefoot with proper hoof care during the winter.

Second, adequate water, above 40 degrees Fahrenheit, should be available at all times. If water sources freeze, the ice should be broken at least twice per day. Owners should NOT rely on horses eating snow for their water supply. A 1200-pound horse will require 12-15 gallons of water per day during cold weather. Having inadequate water available or water that is too cold for horses to drink comfortably may contribute to impaction colic. A horse that does not have adequate water available will also decrease feed intake, which may lead to loss of body condition. Salt should be available free choice, preferably loose salt rather than a salt block as horses may not lick a cold salt block.

Third, provide shelter from cold rains and wind. Horses remain remarkably comfortable in cold weather if they are dry and have shelter from the wind. Cold rains mat down the hair coat, reducing the insulation value of the hair and causing the horses to lose body heat.

Fourth, feed more! A horse’s digestible energy requirement increases for each degree below the thermal neutral zone. Wind chill increases the energy requirement also. Hay or high fiber products produce more heat during digestion than do grains, so adding extra good quality roughage to the diet is a good option. Grain intake can also be adjusted to maintain the desired body condition, but needs to be adjusted gradually.

  • A 1200 lb. horse at maintenance requires about 17.7 Mcal (17,700 Calories) of DE for maintenance.
  • Each degree C below Lower Critical Temperature (Anywhere from 5 degrees C or 40 degrees F down, depending on what the horse is used to.) increases DE requirement about 2.5%. (NRC, 6th Edition, page 10-11.)
  • Converting to Fahrenheit, each degree drop requires about 1.375%, so if the temperature drops from 10 degrees F to 0 degrees F, the DE requirement may increase 13.75% to 20.13 Mcal or 20,130 Calories.
  • This increase of 2430 Calories would require an additional 2.8 pounds of alfalfa grass hay to maintain body condition.
  • If the horse does NOT get the additional DE, the horse could lose a little over a quarter of a lb. per day.
  • If we have 3 months of cold weather, it is very easy for a horse to drop a full body condition score.

Proper winter care will help assure that your horse is ready for winter activities and is ready for spring when it finally arrives!

Feeding Weanlings

Weanling in pastureYou have followed your preferred method for weaning foals and you have followed the directions below:

  1. You made certain that the foals were consuming at least 1 pound of a feed per month of age of a feed designed for foals and weanlings.  6 month old foals were consuming 6 pounds of feed per head per day.
    1. Appropriate feeds will be 14-16% protein with controlled starch and sugar along with amino acid, mineral and vitamin fortification designed for young growing horses.
  2. You kept in mind that past 2 months of age, the milk produced by the dam was not sufficient to maintain adequate growth, so the foals were creep fed if possible as not all mares allow the foal to eat with them.  The foal also had access to high quality forage, loose salt and fresh, clean water.
  3. You made certain that the foals were vaccinated for appropriate diseases and de-wormed according to your health care plan.  Vaccination is a stress on the animal, so you did not do this at the same time you weaned the foals
  4. The foals have been handled, taught to lead and have had their feet trimmed.

Now What?

You need to monitor the weanlings/early yearlings fairly closely and adjust feed intake to maintain desired growth rate and healthy body condition, feeding according to both weight and Body Condition Score (BCS).

  • Weanlings at 6 months of age that will mature at 1200 lbs. may be gaining 1.5+ lbs. per head per day.
  • The objective should be to maintain a smooth and steady rate of growth and a BCS of about 5.

Why Does My Weanling Have a Pot Belly?

Some weanlings become a bit pot-bellied, do not gain muscle mass and look a little rough following weaning.  This is frequently due to inadequate concentrate feed intake and too much forage.  The cecum is NOT fully developed in the weanling, so it cannot digest forage as efficiently as an older horse.

If a young growing horse is not getting the essential amino acids from a well-balanced concentrate, muscle development is slowed down.  If it is not getting the appropriate minerals, the risk of developmental orthopedic problems may increase.

How MUCH Should You Feed a Weanling?

A 6 month old weanling may be consuming 2.0-3.5% of bodyweight in feed and hay per day as fed and should be consuming about 70% concentrate and 30% forage.  At 12 months of age, the growth rate will slow down to about 1-1.25 lb. per day and the yearling will be consuming about 2.0-3.0% of bodyweight in feed and hay per day as fed and the concentrate to forage ratio will drop to 60:40.

As the young horse grows, the rate of growth slows down and the amount of forage it can digest efficiently increases.  Digestible Energy (DE) intake drives growth, but requires the right balance of amino acids and minerals to achieve healthy growth.  Too much DE without the right balance might lead to excessive BCS (fat!) with lack of muscle gain and may increase risk potential developmental orthopedic issues.

Proper preparation can minimize the stress of weaning for foals and help maintain uniform growth and body condition in the weanling to yearling transition to help develop a sound equine athlete.

Blue-Green Algae – A Potential Hazard for Horses, Pets and People

drinkingCurrent weather and water conditions in many parts of the country have created conditions favorable for the rapid growth of blue-green algae. Please be on alert with your horses and dogs, and use precaution when around unfamiliar water sources.

These primative organisms are actually algae-like bacteria instead of being true algae and are also referred to as Cyanobacteria.  They grow rapidly and may produce the pea-soup green color in some bodies of water, along with some foul odors.  These rapid growth periods, called “blooms” most frequently occur when there is a combination of warm weather, intermittent or limited rainfall and an accumulation of nutrients, particularly phosphorus and nitrogen.

The planktonic groups produce the pea green water while the mat-forming groups produce dark mats that start on the bottom and float to the surface.  The planktonic species (Anabena, Aphanizomenon and Microcystis) are believed to be most likely to produce toxins which can be harmful or fatal to animals when ingested. (Fact Sheet on Toxic Blue-Green Algae, Purdue University, Carole A. Lembi)

These toxins may be ingested when animals drink the water or when they lick their coats after being in the water.  Animals are more likely to consume the water if fresh water supplies are limited from other sources.  Any animals that drink the water during a period when toxins are being produced may be affected, but toxins are not always produced when there is a bloom.

Providing a source of fresh, clean, safe drinking water is the best way to avoid causing animals to consume questionable water.  If pets go swimming, they should be cleaned off before they have a chance to lick their coats.

Toxic symptoms may include:

  • Vomiting
  • Diarrhea
  • Rash and skin irritation

Preventing run-off of nutrients into ponds and lakes is also important to help reduce the risk of these algae blooms.  Prolonged drought conditions in some areas have also increased the concentration of nutrients in the remaining water in ponds and lakes.

While not all “blooms” may produce toxins, avoiding exposure to or consumption of suspect water is recommended.  More information is available from local and state pollution control sites or extension sites.   A recent case in Minnesota reported that 2 pets had been killed and a boy was sent to the hospital (MPLS Star Tribune, July 4, 2015, Liz Sawyer) due to exposure to blue-green algae.

What are Essential Amino Acids in Protein, and Why Do They Matter?

Nutrition articles frequently refer to protein quality and essential amino acids. When we use the term crude protein, we are essentially talking about a calculation based on measured nitrogen. Protein is about 16% nitrogen by weight, so if we measure the amount of nitrogen and multiply it by 6.25, this gives us a measurement of crude protein. It does not tell us anything about the quality of the protein. If you tested pure nitrogen this way, it would be 625% protein!

Digestible protein is that amount of the protein that is actually digested by the animal. In an over simplified example, if you fed 100 grams of protein and measured 50 grams in the feces, the protein would be 50% digestible.

What is really important to simple stomached animals (horses included) is the content of essential amino acids in the protein. We commonly talk about 10 essential amino acids (EAA), the amino acids that must be in the diet as the animal cannot synthesize them. These are:

  • Phenylalanine
  • Valine
  • Threonine
  • Tryptophan
  • Isoleucine
  • Methionine
  • Histidine
  • Arginine
  • Leucine
  • Lysine

A common memory aid in many nutrition texts books is to use the first letters of these 10 as PVT TIM HALL. (All of you who had a non-ruminant nutrition course still remember this acronym!)

The other 12 amino acids can generally be synthesized in the body and do not need to be in the diet, although there must be a supply of appropriate substrate to produce them. Animal nutrition text books cover this topic in excellent detail.

Limiting Amino Acids

Limiting Amino Acids

When we talk about limiting amino acids, these are the essential amino acids most likely to be restricting the use of the total amount of amino acids present. In most species, lysine is the first limiting amino acid, with methionine and threonine close behind. We commonly talk about amino acids as the building blocks of protein. If you are once you run out of an essential amino acid, you cannot build any more animal protein and the rest of the amino acids are used inefficiently for energy.

If you have a horse on a diet that is calculated to have adequate “crude protein”, but essential amino acids are not present, the horse simply cannot use the protein to build and maintain muscle, hair, hoof and skin and you will see changes in the appearance of the horse, such as loss of muscle mass, rough hair, scaly hoof surface.

Does My Senior Horse Need Calories or Protein?

hand feeding red sizeThere are some common questions come up when we talk about what happens to horses as they age and why their bodies change shape:

  • Does my good old horse need more calories (energy) or more protein?
  • He is out on good pasture and is holding his weight, but his hair coat looks dull and he has lost muscle mass.
  • She looks a little thin, should I add some fat/oil to her diet?

These are all apparently simple questions, but actually we need to look at the nutrient supply and purpose a little closer.

Calories from fat/oil, digestible fiber (structural carbohydrates and starch & sugar (non-structural carbohydrates) are the key energy sources for horses. If a horse is thin, that tells us that the horse needs more Calories to maintain fat cover measured by Body Condition Score system. Those Calories can be added from extra fat/oil, extra digestible fiber or additional starch and sugar. Vegetable oil contains 2.25 x the Calories per pound of carbohydrates and is a safe way to add Calories. Switching to a highly digestible fiber source (better quality forage, added beet pulp etc.) can also add Calories of digestible energy (DE). It takes 2-3+ pounds of added feed to add 1 pound of gain, depending on the feed.

Adding Calories alone will not bring back the muscle mass. This will require added protein (really added essential amino acids, particularly lysine, methionine and threonine, the first 3 limiting essential amino acids). If a horse is getting adequate crude protein, but the protein is of limited quality and is low in one or more essential amino acids, the horse will not be able to utilize it fully to maintain or restore muscle mass. This is why it is essential to know the quality of the protein in feeds, particularly these first 3 limiting amino acids.

A common situation is an old horse retired to a grass pasture. It may be difficult for the horse to consume enough to maintain body condition, thus the horse loses weight. The grass pasture may also be low in crude protein and certainly low in essential amino acids, so the horse also loses muscle mass. Tough combination for an old friend!

The good news is that this can be reversed with the use of a well-designed senior horse feed providing both Calories and essential amino acids!

Feeding Sunflower Seeds to Horses

Sunflower Seeds_Snack and Black Oil_BRSunflower seeds come in 2 basic classifications with some specialized varieties in each. Black oil sunflower seeds are primarily produced for sunflower oil production, and striped sunflower seeds are primarily produced for confectionary/human consumption.

  • Black oil sunflower seeds will be about 17% protein, 44% fat and 24% neutral detergent fiber (NDF).
  • Striped sunflower seeds will be about 16% protein, 24% fat and 40% NDF.

The hull of the sunflower is fairly tough and is not very digestible and the horse may not break all of the hulls when eating the seeds, so some may pass thru undigested. (The birds in your pasture will appreciate this!).

The black oil sunflower seeds are most readily available for purchase in bagged form as they are also popular for feeding birds and are the most widely used by horse owners. The oil content of black oil sunflower seeds is about 29% Omega 6 fatty acids and about .09% Omega 3 fatty acids. The oil is high in polyunsaturated fatty acids, which is why it is popular for human use.

The key element to consider in deciding if there is a good reason to use black oil sunflower seeds is to consider what you are actually adding to the diet and at what cost.

  • Current bagged retail price may be about $16.00-$20.00 per 20 pound bag.
  • This translates to $1600-$2000 per ton, which is fairly spendy for a horse feed!

If you feed a pound of black oil sunflower seeds, you are adding about 7 ounces of oil (less than a cup) and 2.72 ounces of protein with minimal digestible NDF or other nutrients. If you buy bulk soy oil, you should be able to add more oil at lower cost by adding straight oil and you will have a better Omega 6/Omega 3 ratio.

Black oil sunflower seed use for horses needs to be assessed basis what the ingredient actually adds to the diet and what the cost is compared to other ingredients or feeds.

Selenium Levels for Horses

Henry MusclesAs a horse owner, you may have heard about selenium levels and that you need to be concerned with them.  But why?

Technical reason: selenium is a key trace mineral in equine diets because it is a major component of glutathione peroxidase, which is an anti-oxidant enzyme, as well as several other enzymes.

  • Selenium also has an important interaction with Vitamin E.
  • Selenium and Vitamin E together are essential for both anti-oxidant benefits and for reducing the risk of certain muscle problems such as white muscle disease and exertional rhabdomyolysis syndrome.

Why you should care: Because selenium can also be toxic at higher intakes, it is also the only trace minerals regulated by the FDA.  Most of the U.S. is selenium deficient in soils (and thus toxicity is not an issue in those areas), but there are some areas with high selenium in the soil where some plants accumulate unacceptable levels of selenium in forage and may cause chronic toxicity. If you aren’t sure about the levels where you live, ask area horse owners, farmers, or your local extension office.

How much is in the feed?

In the case of selenium, the label guarantee, which is “added” selenium, is listed in ppm = parts per million = milligrams per kilogram. The actual content will be slightly higher as there is naturally occurring selenium in the ingredients. The labeling requirement is based on added selenium per FDA guidelines.

  • Premium horse feeds are commonly tagged at 0.6 ppm selenium, or 0.6 mg/kg of feed.
  • This equals 0.273 mg per pound of feed. (0.6 mg/kg divided by 2.2 kg/lb. = 0.273 mg per pound of feed)
  • Thus, if you feed 5 lbs per day of a 0.6 ppm selenium feed, you are providing 1.365 mg of selenium per day.

FDA requirement limits added selenium in feed to a maximum of 0.3 ppm concentration in total diet. This is why the maximum on complete feeds – feeds that include enough fiber to replace the hay/pasture portion of the diet – is 0.3 ppm.

On feeds which can be fed at a maximum of 50% of the diet (not that horse owners generally feed it that high), the limit is 0.6 ppm added selenium. Chronic selenium toxicity occurs at about 10X the FDA limit, so there is a pretty good safety margin.

How much does a horse actually need?

A horse’s basic daily requirement for selenium is 1-3 mg per day.  Some chronic selenium symptoms might appear above 10-15 mg/head per day.

To figure out what your horse is consuming, have your hay/pasture supply tested, and then add the amount it is consuming from the hay, to the amount it is consuming from any feed & supplements, and you will know if you need to make any adjustments to your horse’s overall diet.  Depending on your area, it may also be useful to consider intake from water sources.

Manage Pasture to Help Control Horse Feed Costs

Widgy in Grass_BRManaging pasture can be a very important tool in controlling feeding cost for all livestock, particularly horses being kept on small acreages.  If pasture is going to provide a substantial amount of the required nutrition for a horse, it takes about 2-3 acres per 1100 pound adult horse.

There are a number of key steps in managing pastures, particularly small acreages

  1. Do not turn the animals out on pasture too early in the spring.  Forages need some growth to recover from the winter and allow root systems to develop.
    1. Do not turn animals out on tall cool season grasses such as brome grass and orchard grass until the plants are 8-10 inches tall.
    2. If pastures are short cool season grasses such as Kentucky blue grass or rye grass, the plants should be 6-8 inches tall before grazing.
    3. If you do not know your pasture composition, err on the side of allowing adequate growth before grazing.
  2. Remove animals from the pasture when plants are grazed down to 3-4 inches in height.  Grazing too early or too long and allowing animals to eat the grass off too close to the ground will kill the grass and turn the pasture into a dirt lot where the only green plants are weeds, requiring expensive renovation.
  3. If you have limited acreage, consider purchasing some temporary fencing so that you can rotate the pasture.
    1. The outer fencing should be a safe, permanent fencing.
    2. You can cross fence the pastures with temporary fencing such as capped steel posts and appropriate electric wire.
    3. By allowing the animals to graze one section, then moving them to another section to allow the first section to recover, total pasture yield can be increased substantially, helping to control total feed costs.
    4. Clip and drag the pastures after you pull the animals off to control weeds and control parasites and flies.
  4. Make certain that fresh clean water is available at all times and that salt is available at all times.  If you are not feeding a balanced horse feed or ration balancer, offer appropriate mineral free choice as well.
  5. If space is very limited, keep a dry lot area where animals can be fed and watered to prevent areas of pasture from being overgrazed.
  6. Check with your local extension team for additional recommendations for your area and for recommendations on fertilizing pastures.  Dr. Krishona Martinson at the University of Minnesota, St. Paul, MN has published some excellent guidelines for pasture management.

A small investment in supplies to allow pasture to be managed and rotated can pay for itself in higher pasture yields.  Managing the pastures and selecting the right feeds can help manage total yearly costs as well as improve animal health and condition.