Lecture 4: Equine Nutrition Flashcards
What is function of stomach
Enzymatic breakdown
What is function of SI
Digest rapidly available carbohydrates and readily accessible protein
Where do horses obtain most of their protein
Directly from food during digestion in foregut
What is the function of the cecum
Some carbohydrates and proteins in the cell wall of plants will escape digestion in SI and move to hindgut for fermentation.
Where cellulose is broken down
What is the function of the colon
Reabsorption water and some further fermentation
Are horses foregut or hindgut fermenters
Hindgut
Where does microbial fermentation occur and what does it allow for
Occurs in cecum and colon and allows horses to breakdown cellulose
Fermentation in hindgut produces __, ___, and ___ which are absorbed through intestinal wall
CO2, methane, and VFA’s
What is used for glucose production
Propionate
__ is converted to acetyl CoA and used for immediate energy or for fat synthesis
Acetate
Butyrate is also converted to ___
Acetyl CoA
Hindgut digestion is largely ___ and not ___ as in foregut
Microbial, enzymatic
What are some disadvantages relative to ruminants
- Less efficient
- Less dietary nutrients entering hindgut so less microbial growth
- Passage through hindgut is rapid so less fermentation
- Less efficient at absorbing vitamins and proteins
- Protein present in microbes is not digestible and thus lost
What % of BW should horses consume in water
5%
How many gallons per day should horse drink
7 gallons
How much feed should horse get
1.5-3% BW or 15-30lbs
What is main energy source in food
Carbohydrates
How much protein should horses eat/day
550-1000 grams, 12% dry matter
Deficiency in protein can result in __ and ___
Potbelly and poor top line
VFA’s absorbed from hindgut provide about __% of energy requirements
30%
How much vitamin A should horse have
15,000-22,000 IU
What is vitamin A important for
Night vision, reproduction and immune response
Vitamin A toxicity results in what
Bone fragility and tetratogenesis
How much Vitamin D should horses have
3000 IU
What is Vitamin D important for
Calcium homeostasis
Deficiency in vitamin D can result in what
Rickets
Vitamin D toxicity can result in
Soft tissue mineralization
How much vitamin E should horses have
500-1000 IU
What is the main important function of vitamin E
Antioxidant
How much thiamine should horses have
30-60mg
What is thiamine important for
Carbohydrate metabolism and ATP production
Deficiency in thiamine can cause
Ataxia
How much riboflavin should horses have
20-50mg
What is riboflavin important for
ATP synthesis
What macromineral is important in nearly every pathway
Calcium
Calcium must be in a 2:1 ratio with ___
Phosphorus
How much calcium should horses have
20-40 grams
What is phosphorus important for
ADP/ATP production
How much phosphorus should horses have
14-20 grams
What is magnesium important for
Enzyme and muscle contraction
How much magnesium should horses have
7.5-15 grams
What is potassium important for
Cellular regulation/AP
How much potassium should horses have
25-50 grams
What is sodium important for
Cellular regulation/AP
How much sodium should a horse have
10-40 grams
What is chlorine important for
Acid-base and osmotic regulation
How much chlorine should horses have
40-90 grams
What is sulfur important for
Amino acid formation
How much sulfur should horses have
15-18 grams
What is selenium important for
Needed for glutathione peroxidase and thyroid hormone metabolism
How much selenium should horses get
1-3mg
What is zinc important for
Component of many enzymes