Equine nutrition

Question 1

Describe the components of a horse diet

Answer 1

Forage
Roots, succulents and by-products
Vegetable and fish oils
Concentrates

Question 2

Describe the importance of forage/roughage in horse diets

Answer 2

Should be main component
Can provide complete diet (with added vitamin and mineral supplementation)
Required for healthy digestive system (teeth, intestines)
Fulfils horses psychological need to chew
Chewing stimulates saliva which buffers stomach acid

Question 3

Describe the components of hay in horse diets

Answer 3

High in fibre
low in digestible energy and starch
High in Ca and K
Low in P
Contain vit A, E and K (and D if sun cured)
Variable protein

Question 4

Describe the importance of hay storage

Answer 4

Poor storage => ragwort (poisonous) and dust (bad for airways)

Question 5

Describe the features of soaking hay

Answer 5

Hay submerged in water for long period
causes nutritional leaching
good for horses on restricted diets (removes water soluble carbs, dust and spores but still need to chew)

Question 6

Describe the features of steaming hay

Answer 6

Reduces mould, dust and spore content (and some water soluble carbs)
Nutritional leaching
Good for horses with resp issues

Question 7

Describe haylage in horse diets

Answer 7

Retains moisture content
Minimal dust and spores
Contains lots of VFAs which is high energy source
More needs to be fed than hay to achieve same amount of dry matter gained

Question 8

What can occur if mouldy haylage is given to a horse?

Answer 8

sever illness
botulism

Question 9

Describe concentrate feed in horse diets

Answer 9

Fed when horse needs more energy
Low in fibre
high in digestible energy and starch
low in Ca and vitamins
palatable

Question 10

Describe the features of balancers in horse diets

Answer 10

provide essential micronutrients that may be lacking in current diet
low in sugar and starch
good levels of protein, vits and mins
should be given to horses on forage only diet

Question 11

Describe amino acid deficiency in horse diets

Answer 11

Lysine only AA that can be deficient from forage - leads to growth issues

Question 12

Describe starch in horse digestion

Answer 12

hydrolysed by digestive enzymes to glucose sub-units in SI
Primarily found in grains, warm season grasses and legumes

Question 13

What is the effect of feeding excess starch to horses?

Answer 13

Takes long time to digest so passes into caecum and gets fermented => produces lactic acid => lower pH => kills bacteria => dead pathogens enter blood stream => laminitis

Question 14

Describe water insoluble carbs in horse digestion

Answer 14

cannot be digested by digestive enzymes
undergo bacterial fermentation to VFAs in LI

Question 15

Give examples of water insoluble carbs in horse diets

Answer 15

Cellulose and hemicellulose - found in hay

Question 16

What are non-structural carbs (NSC) in horse diets

Answer 16

a measure of hydrolysable carbs specific to horses
Water soluble carbs:
- simple sugars
- di- and oligo-saccharides
- some polysaccharides
Ethanol soluble carbs:
- sugar
- glucose
- fructose
- fructans
Starch

Question 17

Describe the effect of environmental temp on NSC an fructan in equine diets

Answer 17

if not correct sunlight or temp grass generates and stores sugar as fructans and it cannot be used for growth
Low environmental temp => higher sugar concentration
Grass eaten by horse in colder temps => fructan enters hindgut => bacterial death, endotoxins in blood and laminitis

Question 18

Give examples of water soluble carbs

Answer 18

Pectin - found in sugar beet and apples
Fructan - in grass (can affect microbacteria if too much eaten)

Question 19

Give examples of carbs that are fermented in horses?

Answer 19

Cellulose
hemicellulose
pectin
fructan

Question 20

Describe fat soluble vitamins in horse diets

Answer 20

A and E - found in pasture and hay
D - synthesised when skin exposed to sunlight and found in sun cured forage
K

Question 21

Describe water soluble vitamins in horse diets

Answer 21

Vitamin B complex and K:
- synthesised by microbes in LI
C:
- horses can synthesise this

Question 22

Why are salt licks recommended for horses?

Answer 22

commercial diets and forage are usually low in Na and Cl

Question 23

What methods are their for assessing equine weight and body condition?

Answer 23

BCS (out of 5 or 9)
Equine weight-tape
electronic scales

Question 24

What individual considerations are there when planning an equine diet?

Answer 24

Age
Physiological state:
- pregnant
- lactating
- growing
- over/under weight
- nutritional disease
- behavioural issues
Individual preference
Owners circumstances

Question 25

What is the recommended dry matter intake for horses?

Answer 25

2% BW per day

Question 26

Describe donkey diet

Answer 26

Efficient at digesting poor quality fibre - straw should be majority of diet
Low energy requirement
Browsers and grazers
Vit and min provision via daily balancer

Question 27

What issues can a poor equine diet cause?

Answer 27

poor performance
abnormal behaviour
underweight
obesity
equine metabolic syndrome
dental overgrowths
equine gastric ulcer syndrome
colic

Question 28

Why is roughage important for dental health in horse diets?

Answer 28

increase chewing => prevent sharp points

Question 29

What are nutritional causes of laminitis?

Answer 29

Carb overload
fructan overload
Insulin-induced

Question 30

How does carb and fructan overload cause laminitis in horses?

Answer 30

cannot be broken down by SI digestive enzymes so enters hindgut and gets fermented into VFAs and lactic acid
Lactic acid cannot be absorbed or used => digestive disturbance
Causes death and lysis of bacteria due to acidosis => increased endotoxins in bloodstream

Question 31

Describe the link between laminitis and equine metabolic syndrome (EMS)

Answer 31

EMS characterised by obesity, insulin dysregulation and laminitis
High levels of NSC (non-structural carbs) in grass => raised blood glucose conc
Insulin dysregulation => hyperinsulinaemia => constriction of blood vessels to laminae