animal nutriton exam 3: horses

What type of fermentation do horses utilize?

Post-gastric (hindgut) fermentation

What is the stomach capacity of a horse and when does it empty?

"2–4 gallons; empties when about 2/3 full"

Why is the horse stomach considered a safety measure?

"Small size helps mobility

What is the capacity of the horse hindgut?

"23–30 gallons

Where are starch sugar fat vitamins and minerals digested?

"Primarily in the stomach (foregut)"

What happens to fiber and remaining protein?

"Moves to hindgut where bacteria produce VFAs"

When are peak grazing times?

Just after dawn and before dark

How long do horses graze daily?

"10–17 hours per day in 15–20 periods"

What percent of time do horses eat?

"~70% daylight and 50% nighttime"

What happens with low roughage diets?

Development of oral vices

How often should horses eat?

"No more than 2–3 hours between eating periods"

What are spot grazers?

"Horses selectively graze specific plant parts using lips and incisors"

How does weather affect grazing?

"Heat impacts most; wind rain snow also reduce grazing"

Why is too much grain dangerous?

"Excess starch bypasses foregut digestion and disrupts hindgut fermentation"

List steps of starch overload

"Starch overload; lactic acid production; decreased pH; fiber bacteria die; toxin release; colic and laminitis"

Safe grain feeding limit?

5 lbs or less per feeding

Proper feeding order?

"Forage first

Recommended Body condition scoring for broodmares?

"At least 5

When does most fetal growth occur?

Last trimester

Can mares be pregnant and lactating simultaneously?

"Yes

When does milk production peak?

First 2 months after foaling

Feed intake rule for lactating mares?

"2.5–3 kg feed per 100 kg body weight"

When do foals begin eating solid food?

"Within days of birth

Foal feed nutrient requirements?

"16% protein

What is creep feeding?

"Special feed accessible only to foals"

When are foals weaned?

4–6 months

Why prefer optimum over maximum growth?

"Prevents mismatch of cartilage and bone growth"

What is osteochondrosis?

"Failure of cartilage to mineralize properly

What is physitis?

"Inflammation of growth plates causing enlarged painful joints"

What are limb deformities?

"Structural issues like knock knees or upright stance"

What causes developmental orthopedic disease?

"Mineral imbalances and excess dietary energy"

Exercise categories for horses?

"Light 1–3 hrs; Moderate 3–5 hrs; Heavy 4–5 hrs; Very heavy racing/endurance"

Diet changes for heavy exercise?

"High-quality forage and 4–8% fat supplementation"

What electrolytes must be replaced daily?

"Sodium potassium chloride"

Signs of colic?

"Rolling kicking sweating discomfort"

What is laminitis?

"Inflammation of hoof tissues causing pain and lameness"

What causes laminitis?

"Excess grain or lush pasture intake"

Examples of fatal toxic plants?

"Serviceberry elderberry foxglove oleander yew"

Plants causing photosensitization?

"St. Johns Wort and buckwheat"

Ideal stocking rate?

"1.5–2 acres per horse"

Optimal grass height?

"4–6 inches"

Why avoid feeding on ground?

"Increases waste and parasite transmission"

size comparison of hindgut to the stomach

hindgut is 10x larger

eating periods are rarely separated by more than

2-3 hours

what is the best type of grain to feed horses

oats

oats nutritive profile

• 53% starch

• 12% protein

• 12% fiber

what percent of starch do grasses have

less than 10%

how is selectivity and availability correlated in grazing

selectivity decreases with decreased availability

when do requirements begin to increase during gestation

the 5th month

the greatest weight gain occurs during

second or third trimester of gestation

how much weight does a mare gain during pregnancy

60-70kg

when is milk production the highest

the 2 months after foaling

when do foals start consuming significant amount of hay, pasture, or grain

by 2 months

can body weight/ growth rate in foals be estimated if expected mature body weight is known

yes

crude protein, calcium, and phosphorus levels for nursing foals

16% CP, 0.9% calcium, and 0.6% phosphorus

should foals be given unlimited access to feed

no

daily concentrate intake for foals

0.2-0.5kg/month of age

what age does the total nutrient requirements begin to not be from milk

around 3 months

what age is feed needed regardless if weaned or not

4 months

how much of the foals daily nutrient requirement will come from milk at 6 months old

less than 50%

adult size is based on

genetics

what is desired instead of maximum growth

optimum growth

how can DOD affect horses in the long run?

may affect their soundness and future athletic capasity

what minimizes the chances of DOD

balanced diets

what feeding practice should be done if a body condition of 50:50 cannot be maintained during heavy excersie

• use highest quality forage

• consider using fat (4-8% higher fat ration)

what minerals are affected by significantly sweat losses (3)

• Na

• K

• Cl

electrolytes are not

stored, needed daily

what are 2 factors that can cause colic

• sudden change in diet

• lack of water availability

what are the 2 reasons to avoid feeding directly on the ground

• greater feed wast e

• increased potential for transmission of parasites

when feeding hay in a group, how do feeding allowances change

should be 10-20%