Feed evaluation Flashcards
what factors need to be considered for a proper ration
environment
intake
output-input
why is intake important
if they eat less than you plan for their requirements arent being met
what percent of lysine do early weaned pigs need
1.6%
what 2 ways can dietary standards be expressed as
quantity of nutrient
percent of diet
what is the biggest priority in feeding standards
energy
units for feeding standards
NE
ME
DE
TDN
T/F dairy cows have a higher percentage of consumed energy going towards maintenance than beef cows
FALSE> most of dairy cows energy goes to milk production
what is the relationship between heat production and bodyweight
non linear
as one increases so does the other
what is the relationship between heat production per unit of boy weight and body weight
as body weight increases heat per unit decreases
what is metabolic body size, what is it used for
BW^0.75
used to predict maintenance energy requirements
equation for heat production related to body weight
HP = 70 x BW^0.75
how does rate of gain effect NEg
the faster you grow the higher your energy requirements
how does composition of gain effect NEg
fat composition will require more energy than muscle composition
T/F bulls leaner than steers leaner than heifers
TRUE
what happens to energy requirements as you mature
fat increases increasing energy requirements
how does frame size impact energy requirements
as frame size increases so does energy need
when does the fetus truly begin to increase energy requirements
3rd trimester
types of diets that can be formulated
-total mixed ration
-trace mineral mix
-energy/protein supplement
-vitamin/mineral premix(to be mixed in with total mixed ration)
factors affecting feed intake in swine
-body weight
-temp
-pelleting of the ration
-subtherapeutic levels of antibiotics
-space
-gender
-protein
-breed
how do subtherapeutic levels of antibiotics effect feed intake
feed intake increases
T/F barrows eat more than gilts eat more than boars
TRUE
which breed of swine has the highest feed intake
Durocs
why is breed less of a indicator of feed intake in swine now
most swine are crossbred
factors effecting feed intake of cattle
-dietary energy concentration
-empty body fat
-breed
-implants
-ionophores
-temp
how does energy concentration effect intake
very low or very high energy levels will have decreased intake
which cattle breed has the highest feed intake
holstein
how do implants effect feed intake
implanted cattle consume more feed and produce more muscle than fat
how does rumensin impact feed intake
rumensun causes a decrease in intake but not a performance change
what is the purpose of rumensin
change composition of microbes to improve feed efficiency
T/F all ionophores cause a decrease in feed intake
FALSE
methods to formulate rations
linear programming
least-cost
commercial software
