5b Life Cycle Nutrition of Horses 1

Question 1

What are the 4 nutritional phases during the first 12 months?

Answer 1

1. Nursing for first few weeks
2. Incorporate solid feeds ~10 days postpartum
3. wean ~6 months of age
4. continue rapid growth to 12 months of age

Question 2

Describe the importance of colostrum in the first 24 hours.

Answer 2

• rich in protein, dry matter and vitamin A
• contains immunglobins (absorbed through small intestinal)
• efficiency of absorption declines after 12 hours postpartum
• no longer absorbed at 24 hours post partum

Question 3

Describe nursing behaviour within the first 24 hours.

Answer 3

• nurse within 1-2 hours after birth
• nurse 10 times/hr in first 24 hours
• nursing lasts about 1-2 min
• consume 15% BW as milk in first 24 hours

Question 4

What is the digestibility of milk?

Answer 4

98%

Question 5

How long does milk supply all nutritional needs?

Answer 5

6-8 weeks

Question 6

How does total solids, energy, protein, fat, lactose and minerals change in milk as time passes?

Answer 6

• total solids decrease
• energy decreases
• protein decreases
• fat decreases
• lactose increases
• minerals decrease

Question 7

Why do so many nutrients decrease in milk?

Answer 7

• encourages weaning

- foal will naturally try to supplement diet by weaning

Question 8

How is the composition of mammals milk related to growth rate of the young animal?

Answer 8

Protein, Ca and P increase as the ‘days required to double birth weight’ decreases

Question 9

How many days do horses require to double their birth weight?

Answer 9

• 60 days

Question 10

In what order are tissues deposited as the horse grows?

Answer 10

bone then muscle then fat

Question 11

How does the tissue order of deposition affect the nutritional requirement of certain ingredients?

Answer 11

• will require calcium and phosphorous first and most importantly for bone development

Question 12

At 1 month of age, what percentage of height has been reached?

Answer 12

90%

Question 13

If nutrition is compromised in the mare, how does this affect the foal?

Answer 13

• during pregnancy,, will divert energy to foal
• however, during lactation, may result in reduced milk production
• can wean early to prevent this affecting growth

Question 14

Does weaning age affect growth rate?

Answer 14

• little influence
• initial colostrum necessary for regular growth
• weaning dependent on management practices

Question 15

At what age do foals spend ~50% of their day eating solid feed?

Answer 15

• 21 weeks
• dam allows foals to eat grain, especially if in confined box stall
• seek solid food source for nutrient supply
• copies dam

Question 16

Describe creep feeding.

Answer 16

• provides nutrient dense source of feed to foals but is protected from ingestion by mares
• helps reduce weaning stress
• adapt micro biome
• increased ADG from foals not creep fed
• voluntary intake varies between foals

Question 17

Where does growth of long bones occur?

Answer 17

• metaphyseal plates (growth plates)

Question 18

What is an easy way to tell if a foal is not done growing?

Answer 18

• croup is higher than shoulder

Question 19

What is the general energy requirement for growth?

Answer 19

• energy for growth = energy for maintenance + growth

Question 20

As the growth rate slows, does the energy required for 1kg gain increase or decreases?

Answer 20

• increase

Question 21

Describe the protein requirements for growth

Answer 21

• sensitive to protein quality

- lysine is first limiting AA

Question 22

How can protein requirements be determined?

Answer 22

• nitrogen balance should be positive in growing horses

Question 23

Describe calcium requirements in growing horses.

Answer 23

• deficiency can lead to osteopenia (problem with remodelling)
• poor mineralization of osteoid tissue
• creates enlarged joints and crooked long bones
• Ca requirement = maintenance + gain

Question 24

Describe the result of phosphorous deficiency in growing horses?

Answer 24

• rachitic like changes
• excess reduced Ca uptake
• can lead to nutritional secondary hyperparathyroidism

Question 25

What does PTH do?

Answer 25

• increased from bone
• decreased in urine
• increased from intestine
• in response to low blood calcium

Question 26

Describe nutritional secondary hyperparathyroidism.

Answer 26

• inadequate dietary Ca due to low Ca or high P
• Ca:P needs to be 2:1 for growing horses
• manage by altering diet
• prevent by providing right ratio or supplement with Ca carbonate

Question 27

Describe development orthopaedic disease.

Answer 27

• complex of musculoskeletal abnormalities (angular limb deformities, physics, subchondral bone cysts, osteochondrosis)
• occurs in as much as 80% of horses (corrective trimming, surgical correction)
• cervical vertebral malformation can cause compression of spinal cord
• idiopathic (hereditary) or acquired (trauma or nutritional)
• originate from abnormalities of growth plate
• found in horses with high ADG

Question 28

What are the nutritional causes of DOD?

Answer 28

• excessive energy intake
• may cause hormonal abnormalities if high non fibre CHOs fed
• try to increase energy with fat
• must regulate feeding to prevent
• high protein have no effect on DOD
• imbalances of Ca and P

Question 29

How can DOD be prevented?

Answer 29

• regulate feeding
• copper supplementation
• voluntary exercise