what do horses eat?
- hay-grassoralfalfa
- pasture
- concentrate-pellets, sweet feed or extruded kibbles
- beet pulp, COB, soy hulls and/or cubes
- mineral and performance suplements
- biologicals, pre-biotics, pro-biotics
- water
principle of the first limiting nutrient
- Justus von Liebig’s Law of the Minimums states that yield is proportional to the amount of most limiting nutrient
- performance and health of horse reduced to level of most limited nutrient
6 essential nutrients
- protein
- carbs, including sugars starches, and cellulose
- fat
- macro minerals/trace minerals
- vitamins, fat or water soluble
- water
who determines how much to feed?
NRC or national research council
- they determine nutrient requirements through mathematical calculations
- requirements are based on size, age, and metabolic state of the horse, and the body weight of the individual
do you need complicated ration balancing to feed horses
- horses are fed weights of feed, not percentages or volumes
- it is not always necessary to fine tune the rations so long as you know the feed weights and animal’s intake
body weight calculation
- scales are not always easily accessible
- weight tape are easier to get and quite accurate
- calculation in inches: distance from point of shoulder to point of rump * heartgirthsquared/300+50 is weight in pounds
- can also use google for more options
other factors to consider for adjusting feed weight
- lactating or pregnant horses have greater metabolic need and thus more nutrients
- more nutrients needed if undergoing heavy training or moderate work loads
- also young horses with heavy training need more feed
How does environment affect nutritional needs
- horses that are housed have lower energy requirements than those out all the time
- blanketing can reduce energy requirements in cold weather
common factors for successful feeding for horses
- forage quality and access
- frequency of feeding
- other health issues like teeth, parasites
- social order and environment without fear
- access to water
- housing and climate
- age
Winter Management liabilities
- over/under estimating intake and digestibility
- under estimating impact of weather
- under estimating water access and intake
forage quality and horses during winter
-being non-ruminants forage quality must be high especially during winter to ensure proper nutrient absorption
horses and importance of hay
- most have forage as 80% of dry matter intake daily
- non-ruminants so digestion of hay is more difficult, high quality is a must
forage sampling hay
- sample must represent what’s being given
- core sample taken from middle of hay
- sampling should be random, and enough to cover the entire feed, ie. 20 samples per ‘lot’
wet chemistry
- chemicals in a lab are used to analyse the sample for its component nutrients
- drawbacks: time consuming and expensive
- adv: accurate for trace minerals
NIRS
near infrared relectance spectroscopy
- reliable method
- uses infrared light and computer calibrations with math modeling rather than chemicals to identify and predict amount of nutrients
- very accurate, fast, clean, and environmentally friendly
grass hay can be deceiving
- colour, texture, and cut are not good parameters for determining it as good feed
- errors in judgment can have negative impacts for horses
what factors make hay variable?
- genetics
- growing conditions ie fertilizers and water
- harvest conditions, time of day and weather
- maturity
- health/vigour of the stand
- sampling procedure
maturity stage:
-hay quality declines rapidly with age
-protein and minirals decrease as fiber increases
best harvesting time is just before heading and buds come in, at the middle of maturation
reading lab reports for feed
dry matter or As Fed?
- crude protein
- acid detergent fibre (ADF)
- neutral detergent fibre (NDF)
- ethanol soluble carbs (ESC)
- water soluble carbs (WSC)
- starch
- non-structural carbs (NSC)
- digestible energy (DE) Mcal/kg or lb
what is ESC?
ethanol soluble carbs: very simple sugars rapidly digested in stomach of the horse
what is WSC?
water soluble carbs: slightly more complex sugars that may be digested in stomach or cecum
differences between ESC, WSC, and NSC
- ESC plus fructan=WSC
- WSC plus Starch=NSC
- NSC= Non-structural carbs
NSC
- non-structural carbs
- a calculated measurement of all the carb sources that may be digested rapidly to glucose in the stomach or fermented in the cecum
- NSC is the parameter to consider when choosing hay for metabolically challenged horses
large meals of high NSC feeds
- simple carbs and/or excessive fructans cause rapid pH drop in hindgut
- too much rapidly fermenting sugar in cecum can lead to colic, laminitis, diarrhea, and/or gas colic
- feed small meals often!
