This is an outline for upcoming “lectures” at www.equiuniversity.com. To cover this amount of information in-depth, it will take several video series and be completed over several months.

Nutrients:

• Water
  • Most important nutrient to animals.
  • Intake averages about 10-12 gallons per day.
  • Humidity, temperature, ration (diet), exercise, and stage of production will influence intake and needs.
  • Water deprivation may result in:
    • Decreased feed intake
    • Decreased growth
    • Decreased activity and ability to perform work
• • Always provide access to free choice, good quality water.
  • During exercise, allow the horse to drink as often as possible.
• Energy
  • Nutrient required in greatest abundance.
    • Usually measured in kilo or mega calories
    • May be reported as TDN or Digestible Energy
    • Requirement is influenced by individuality, age, type of work, stage of production, environmental conditions, ability of rider, ground conditions, and fatigue
    • Average maintenance requirement for an 1100 lb horse is: 16Mcal
    • Maintenance + 25% for light work
    • Maintenance + 50% for medium work
    • Maintenance + 100% for heavy work
  • Sources
    • Carbohydrates
      • Primarily grains and forages
        • Sugars, Starches, Cellulose
        • Corn, Oats, Barley, Milo
        • Alfalfa, Coastal Bermuda, primarily hays
        • Grains contain more starches and sugars than forages, also more energy
      • May be problematic for certain horses
        • Equine Metabolic Syndrome
        • Horses with insulin dysregualtion
        • Cushing’s Syndrome (PPID)

• • • Fats

• • • • Fats and oils
        • Both contain equal energy content
        • Fats are solid at room temperature whereas oils are liquid at room temperature
      • Contain 2.25x’s energy in grains, energy dense
      • Decrease dust in feed
      • Using fat in the diet will lower the amount of concentrate required to meet the energy needs
      • Adds bloom to the horse
      • Highly digestible, safe way to increase energy content of concentrate
      • Essential Fatty Acids (must be included in the diet)
        • Omega 3 (alpha linolenic) and Omega 6 (linoleic) fatty acids
      • Takes time for adaptation
      • Vitamin E levels should be increased with high fat feeds

• • • Protein
      • May be used as energy, usually when ration is deficient in energy or contains excessive protein
      • Very inefficient as energy source
      • Very expensive energy source
    • Examples of energy content
      • Oats                             1.30 Mcal/lb
      • Barley                         1.48 Mcal/lb
      • Corn                            1.54 Mcal/lb
      • Milo                            1.46 Mcal/lb
      • Alfalfa                        1.00 Mcal/lb
      • Coastal Bermuda     0.80 Mcal/lb
      • Timothy                      0.80 Mcal/lb
      • Vegetable oil              4.08 Mcal/lb
• Protein
  • Composed of amino acids
  • Protein quality, balance of amino acids, is important in the young growing horse
  • Protein requirements are influenced by animal needs, protein quality and protein digestibility
  • Lysine is the first limiting amino acid for growing horse
  • Methionine is a sulfur containing amino acid that may be beneficial in hoof growth
  • Protein requirement as a percent of the ration decreases with age
  • Work does not alter the percent of protein, but the total amount per day will increase
  • Often confused with energy content of feed
  • Sources
    • Soybean meal: most widely used source.
    • Linseed meal: usually low in some amino acids.
    • Cottonseed meal: not widely used for horses.
    • Alfalfa meal
    • Alfalfa hay
    • Others
• Minerals
  • Macro
    • Calcium
      • Makes up skeleton: 99% in bones and teeth.
      • Important in muscle function
      • Blood levels are poor indicators of Ca status in the horse
      • 1100 lb mature horse needs ~ 20g Ca/d (maintenance)
    • Phosphorus
      • Skeleton
      • Energy metabolism
      • Reproduction
      • 1100 lb mature horse needs ~ 16g P/d (maintenance)
    • Potassium
      • Important in acid-base balance
      • Forages and oilseeds are high in K
      • May be affected by activity

• • • Sodium
      • Acid-base balance
      • Affected by activity
    • Magnesium
    • Sulfur
  • Micro (trace)
    • Copper
    • Manganese
    • Zinc
    • Iron
    • Selenium
• Vitamins
  • Fat soluble (stored in the body)
    • Vitamin A
    • Vitamin D
    • Vitamin E
    • Vitamin K
  • Water soluble (usually excreted if not used)
    • Thiamin
    • Riboflavin
    • Niacin
    • Pantothenic acid (B6)
    • Biotin
      • ~ 20mg/d may help hoof quality
      • May be more cost effective to increase methionine intake for hoof issues, source of sulfur
    • Folacin
    • B 12
    • Ascorbic acid (Vitamin C): no known dietary requirement in the horse
• Supplements
• • Vitamin

• • • Vitamin E

• • • • Immune function
      • Muscle issues: e.g. Tying-up
  • Mineral

• • • Salt blocks: average requirement is about 1 oz. per day, higher with work, heat, sweating, etc.

• • • • Not best means of getting salt and minerals into horses
      • Loose salt/mineral mix encourages consistent consumption
  • Vitamin/Mineral

• • • Insure (evergreenequine.com)

• • Joint

• • • Glucosamine: 4000 to 10,000 mg/day
    • Chondroitin sulfate: 1500 to 4000 mg/d
    • Hyaluronic acid (HA): injection, oral
    • S-adenosyl methionine
    • MSM: 10,000 to 20,000 mg/d
  • Other
    • Hematinics: blood “builders”
      • No data in the literature to suggest iron deficiency anemia in horses

• • • Electrolytes
    • Probiotics: microbial cultures
    • Anthelmintic: dewormers
    • Coat conditioners: usually comprised of high fat products
• Combination: kitchen sink approach, usually do not contain enough of any one nutrient to justify use

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