Nutrient and Maintenance Requirements Flashcards
what is referred to as the equine nutrition bible?
Equine NRC
What does NRC stand for?
National Resource Council
Who created the NRC?
National Academy of Science (NAS)
how do we determine nutrient requirements?
research, feeding different amount of the nutrient with a standard diet and measure the responses
a response variable must be what?
measurable, important, not influenced by other dietary factors
can blood concentration of the nutrient of interest act as a response variable?
only sig. for a few nutrients, otherwise it’s poor to use
is hair analysis accurate for nutrition?
no, valid for DNA/color typing though
what does deficient mean?
poor performance
what does marginal mean?
enough to survive, but not perform optimally
what is a requirement?
minumum needed for a function
what is adequate?
minimum required for a desired response
what is optimal?
amount required for max. performance or the response
what is excess?
no added benefit or negative effect
what is toxic?
measurable signs of excess; negative effects seen
does more=better in nutrition?
not always, a plateau is hit when the optimum amount is met; then the response dies during excess before becoming toxic when the response rapidly goes south
issues with equine nutrition?
animals, labor, time= expensive!!
what must we consider when designing an equine nutrition project?
experimental design for variability
are there a lot of studies for specific nutrients across a range of intakes?
no
what is the issue with minimum requirements?
deficiency signs can take months to develop
what is the issue with finding maintenance requirements?
this is very easy to measure! results in no net gain or loss
how can maintenance requirements be estimated?
feces, urine, sweat, respiratory, heat, etc.
does nutrient availability affect requirements?
yes, example: if 100% is available 10g is needed, 50% then 20g needed
what is the nutritionist dilemma?
not enough= underfed, too much=overfed
risks with underfeeding?
reduced performance, health, or production
risks with overfeeding?
excess excretion into environment
better to over or under feed?
over!!
in the ideal world everyone would do what?
test soil and forage (bulk buy forage) balance diets using NRC and tools, assess BCS and weigh
in the real world what happens?
trust forage quality, feed to bag reccomendations, assess BCS and weight
who invented BCS?
Dr. Henneke at TAMU (1983)
what is the BCS scoring range?
1-9
what is BCS measuring?
fat depostion
what regions do we look at when measuring BCS?
withers, elbow, ribs, crease down back, loin, and tailhead
what is the weight estimation formula?
(HGxHGxBL)/ 330 (mature) 301 (yearling) 280 (weanling)
what order do we assess equine nutrition?
assess BCS, weight estimation, current diet evalution, make gradual changes if needed
what are the DE requirements for average, minimum, and elevated metabolism?
average: 0.0333
minimum: 0.0303
elevated: 0.0363
what is the DE Assessment formula?
BW x constant= DE requirements
