Flashcards in 5b Life Cycle Nutrition of Horses 1 Deck (29):
What are the 4 nutritional phases during the first 12 months?
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
Describe the importance of colostrum in the first 24 hours.
- 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
Describe nursing behaviour within the first 24 hours.
- 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
What is the digestibility of milk?
How long does milk supply all nutritional needs?
How does total solids, energy, protein, fat, lactose and minerals change in milk as time passes?
- total solids decrease
- energy decreases
- protein decreases
- fat decreases
- lactose increases
- minerals decrease
Why do so many nutrients decrease in milk?
- encourages weaning
- foal will naturally try to supplement diet by weaning
How is the composition of mammals milk related to growth rate of the young animal?
Protein, Ca and P increase as the 'days required to double birth weight' decreases
How many days do horses require to double their birth weight?
- 60 days
In what order are tissues deposited as the horse grows?
bone then muscle then fat
How does the tissue order of deposition affect the nutritional requirement of certain ingredients?
- will require calcium and phosphorous first and most importantly for bone development
At 1 month of age, what percentage of height has been reached?
If nutrition is compromised in the mare, how does this affect the foal?
- during pregnancy,, will divert energy to foal
- however, during lactation, may result in reduced milk production
- can wean early to prevent this affecting growth
Does weaning age affect growth rate?
- little influence
- initial colostrum necessary for regular growth
- weaning dependent on management practices
At what age do foals spend ~50% of their day eating solid feed?
- 21 weeks
- dam allows foals to eat grain, especially if in confined box stall
- seek solid food source for nutrient supply
- copies dam
Describe creep feeding.
- 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
Where does growth of long bones occur?
- metaphyseal plates (growth plates)
What is an easy way to tell if a foal is not done growing?
- croup is higher than shoulder
What is the general energy requirement for growth?
- energy for growth = energy for maintenance + growth
As the growth rate slows, does the energy required for 1kg gain increase or decreases?
Describe the protein requirements for growth
- sensitive to protein quality
- lysine is first limiting AA
How can protein requirements be determined?
- nitrogen balance should be positive in growing horses
Describe calcium requirements in growing horses.
- deficiency can lead to osteopenia (problem with remodelling)
- poor mineralization of osteoid tissue
- creates enlarged joints and crooked long bones
- Ca requirement = maintenance + gain
Describe the result of phosphorous deficiency in growing horses?
- rachitic like changes
- excess reduced Ca uptake
- can lead to nutritional secondary hyperparathyroidism
What does PTH do?
- increased from bone
- decreased in urine
- increased from intestine
- in response to low blood calcium
Describe nutritional secondary hyperparathyroidism.
- 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
Describe development orthopaedic disease.
- 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
What are the nutritional causes of DOD?
- 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