Nutrition 5 Evaluation of Feedstuffs

welcome the animal science students to

nutrition five evaluation of feedstuffs

the evaluation of feedstuffs is critical

as part of a overall nutritional program

management so first we need to know what

the nutrient week rot requirements how

our animals are and that's going to be

influenced by stage of growth for the

animals productivity level what do we

want what's our goal for average daily

gain are they lactating and what's our

goal four pounds of mouth per day or

litter weighted 21 days cetera so very

important to know what the nutrient

requirements of the animals are next

what are we going to feed our animals

and is amazing all the different things

that we feed animals and we need to

evaluate those feed stuffs very

carefully for amount of energy and

what's going to be available to the


what's the digestibility are there any

anti-nutritional factors for example in

soybeans that you are feeding right raw

soybeans raw soybeans will contain a

substance known as trypsin inhibitor it

prevents the animals from synthesizing

the amino acid trypsin so we generally

have to cook those soybeans first

kostov we don't necessarily want the

lowest-cost ration but we want the best

cause ration the what we pay for fees is

an investment in getting productivity

from those animals ok knew the quality

and availability and how much can we put

a particular feed stuff in before we may

decrease palatability or

so we take all this into account we

formulate the rations then we have to

make sure it's mixed correctly in

process correctly stored correctly etc

and then we make it available to the

animals we want to minimize feed wastage

feed wastage isn't going to be zero

percent but we certainly don't want it

any more than four or five percent feed

wastage and then we monitor the Rize

results and the cost and if everything

works correctly great if we're not at

our optimal performance level we may

have to kind of start over again through

the system here we generally classify

feed stuff into eight different

categories so our drive forages and

rough edges that were include alfalfa

hay grass hay if you know what's the

difference in a roughage and a forager

roughage is generally even higher in

fiber and less nutrient dense than

forages so help I hate grassy I consider

that forage differ feeding straw to an

animal or corn stover which is left

after we take the corn green around way

we might call that a roughage and then

range pasture green forages what are

those range versus pasture in Minnesota

we have pastures range is what you're

going to find out Wessel range landings

generally maybe semi-arid not enough

rainfall for really for quality forage

that you need quite a few acres per

animal out on the range in green forages

sometimes known as green chopper will

take a tractor and chopper and wagon and

go out there and cut the corn or alfalfa

or grass just cut it right off and

right into the animals to eat that's

known as green cha and then our silages

are fermented forages so we take the

whole plant corn silage we chop it up

we'll put it in that oxygen oxygen

limiting structure where that's an

upright style or a funcle' silo or big

silage bag in bacteria ferment the

silage and produce fatty acids and in

this fermentation process we actually

increase the digestibility of the forage

because the microbes start the digestion

process so these three up here can all

known as forages the silage it's the

whole plant it's not as energy or

protein dance as some of other other

feed stuffs down the list here

so any feast of word greater than 80%

protein would be considered in these

three categories here gonna be less

digestible than some of other other feed

stuffs down the line next we let's go

with the energy feed stuffs contains

less fiber so it's more digestible and

less than 20% protein if it's more than

20% protein would probably put it into

the protein supplement category number

one energy feed stuff in Minnesota would

be corn green we grow an awful lot of

corn grain and that corn is used for

different purposes one purpose would be

production of ethanol corn Green is also

used for human consumption if you've had

cornflakes for breakfast for example in

a lot of the corn grain is fed to

livestock to increase the energy density

to get more milk for cow or to make

those pigs grow faster so corn is the

number one energy key stuff that we feed

any grain would be considered a

relatively high in energy because grain

is going to contain starch so oats

barley wheat would all be considered

energy Fiza and then we also make the

plant oils like soybean oil or we may

feed byproducts of the slaughter

industry like tallow or lard to our pigs

to increase the energy density alright

next on the list here protein

supplements contain low in fiber and

high in protein number one protein

supplement in Minnesota would be soybean

meal so we grow a lot of soybeans we

extract the oil for human consumption

and industrial purposes and what we have

left is a soybean meal which is going to

be about 50% protein and the nice thing

about soybean meal the amino acid

content complements very well with the

amino acid profile that we have in corn

grain so soybean meal is the number one

protein supplement distillers grains

would be another protein supplement that

we utilize in Minnesota and then we talk

about minerals and vitamins so

definitely mineral supplements salt

ground limestone diet calcium phosphate

would be mineral supplements and then we

may or may not add vitamins to the

ration in the non-nutritive additives

what would be a non-nutritive additive

well sometimes we add flavoring agents

we may specially do that with companion

animal food we can add food coloring so

when you buy that bag of dog food or cat

food it may be red and green and pika

now food colorings it's not really going

to influence how much your dog is going

to eat but the food colorings more or

less for the humans we can add growth

hormones would be non-nutritive additive

like we can add antibiotics or medicines

to our feed stuffs well first we're

going to evaluate their pieces for

energy content and in our old system was

the TDM system which stands for total

digestible nutrients an animal scientist

came up with the TDM system back over a

hundred years ago already but what is a

TDM it is that I just will crude protein

in a fee stuff plus the digestible crude

fiber now fiber is not gonna be as

digestible as these other components but

we can digest some of the fiber

I just want nitrogen-free extract would

be the starches and the sugars and our

food stuffs and then I digestible five

times 2.25 because fat contains more

energy than these other foodstuffs

now this is an example of the amount of

energy or TEM in 100 grams of a sorna

swine or poultry diet so this would be a

product corn grain based diet balanced

with soybean meal and the minerals and

vitamins needed

so in this 100 grams of feed this would

be a young pigs diet at 20% protein

protein is 75 percent I just for this

pig now if the protein stays and then

they just attract long enough

essentially a hundred percent of it is

digested but as the pigs eat thing some

of the pee stuffs is pushed to before

it's totally digested that's why we're

only at 75 percent here 20 grams time 75

percent digest of all he is 15 grams of

PDM the nitrogen free extract would be

mostly starts 60 grams 85% digestible so

60 times 25 is 51 grams of PD in there

the fiber now our corn grain based diet

is not gonna have that much fiber in but

it's still a 10% fiber

now the fiber is only gonna be 20%

digestible for this pig so we just

getting 2 grams of PD in from the fiber

and we have about 5% fats corn grain is

close to 5% fat so there you go that is

very digestible 85% times a 2.25 so

we're getting quite a bit of energy in

that small amount of fat

so total amount of tedium in our put

together ration here we're at the

seventy seven point five six percent so

our 77 percent TD and our ration would

be considered a pretty high energy

ration the tedium system relatively

simple kind of easy way to balance a

ration and people utilize the TDM system

for many years well currently most

rations are going to be balanced using

the tab Eliza Belen er G or net energy

that's available in that feed stuff

so in this case we're counting calories

just like for human nutrition we're

counting calories now a calorie is the

montigue required to raise the

temperature of one gram of water one

degree Celsius from 15 point five

degrees to sixteen point five degrees

Celsius alright so precise definition

there so you can take any organic

substance and you can burn it and

measure the heat release and you know

how many calories contained in the feed

stuffs all right so for poultry swine

diets we balance it though with

kilocalories now kilocalorie is a

thousand calories based on the

definition that we have up above there

now one kilocalorie is the same as 1

calorie for human nutrition so in human

nutrition way back when somebody cited

that day we don't want to talk about

kilocalories that sounds kind of

complicated we'll just call it calories

in walls use just a capital C so people

know we're talking about kilocalories

well over time people kind of dropped

the capital C when they're talking about


calories we're just talking about

calories but for humans realize when you

say that that cheeseburger contains 700

calories it's really 700 kilocalories

now for our dairy and beef diet since

they're bigger animals and they eat more

just so we have to use fewer digits

we're using mega calories in 1 million

calorie equals a thousand kilocalories

okay so we can burn any fee organic

matter we can burn in the laboratory and

determine how many calories that

foodstuff contains here's the example of

kind of going through these of the

calorie type system here so on average

and it's going to vary but on average

carbohydrate produces 4,000 calories per

gram bafta over twice as much

9450 calories per gram and protein about

the same energy content as we have in

our hydrates so if we've got a sample

feed and we've got four grams of

carbohydrates 20 grams of protein 2

grams of fat that particular little

sample there would contain one hundred

and sixteen point nine kilocalories

so here we have an example of kind of

petitioning out that energy to that cow

is going to consume so typical dairy

cattle ration that we have here it's

going to be probably about 50% crude

fiber so we've got some fiber in there

that's going to reduce the digestibility

so gross energy that is what the cow

consumes that's what goes into our belly

all right now typical dairy kale ration

is going to be saudi percent digestible

30 percent of the energy is going to be

in the feces now of course there's some

places around the world yet where

they'll click the cow pop patties and

then burn them for heat so definitely

there is heat left in energy left in

that fecal material okay what happens to

what's a digestive all right the cow can

utilize it also we lose 5% for urinary

energy now you don't necessarily think

of being able to burn the urine but if

you dry the urine down remove all the

liquid there are compounds there that

contain energy

all right so in the process we're also

gonna have gaseous energy those microbes

digest the fibrous material and they

produce the developed of fatty acids

that the cow can utilize they also

produce methane which the cow burps out

and that's the gaseous energy that's

lost so what we have left is

metabolizable energy all right so that

gets into the cells that these cells can

utilize and if they're metabolizing this

energy an animal's body produces heat in

that account so about 20% on the winter

time under cold weather that's so it's

nice to have that eat when it's a

summertime and it's 95 degrees out well

that heat is not so good but

he created in the metabolizing that

energy component so the girls energy

that goes into the cow 40% can be

utilized by the cow for maintenance and

maintenance just the energy that it

takes to keep the heart pumping 24 hours

a day you need to breathe in and out the

colonies to chew its food etc so that's

going to be the maintenance requirement

and what we have live days for

production in production will generally

by that between and growth lactation and

gestation as far as energy needed for

fetal growth alright we're going to go

through an example of proximate analysis

of a fee stuff and this is a fee that we

may be feeding to a fan finishing Pig

diet where we're at 13% protein in the

diet so starting off here we're gonna do

a dry matter calculation we're gonna dry

this feed down off this will be dry feed

to the touch but it's just air dried so

your great feed is still gonna contain

some moisture usually on that 12% affi

stuff is either moisture or dry matter

the to add to a hundred percent on this

88% dry matter now we've removed the

water ran about five percent ash and

this is the minerals that in the feed

minerals do not burn the organic matter

burns so we can burn it to find them on

a batch okay organic matter at 83% then

when feeding at 13% protein rachet very

typical in a pigs diet so of the organic

matter will remove the protein and what

we have left here is the fats and the

carbohydrates so typical pigs diet may

be four percent fat and corn is about 4

percent corn oil so there you go and

so most the energy though is going to be

in the carbohydrates crude fiber at

about 10% that's the fiber that you have

in that corn or all that seed of corn

the they're covering around the corn

plant then the nitrogen free extract

your sugars starches simple sugars at

about 5% fructose is going to be in that

kernel corn Haley's gonna be mostly

starts it's 50% and then your water

soluble vitamins less well less than 1%

as far as your B vitamins and maybe

smaller modify them and see so we're

just missing the fat soluble vitamins

and the fat soluble vitamins are gonna

be contained back here in the fat so

here we just have our little review on

that proximate analysis we found the ass

heathyr extract which was the fat crude

protein and we've got the carbohydrates

which we include the nitrogen free

extract plus the crude fiber here into

this center column here we have the

different components what we find over

here but one thing about the proximate

analysis which is kind of weak spot is

that as we do the approximate analysis

the crude fiber does not contain all the

fire it contains the cellulose it

contains part of the lignin and lignin

is there indigestible crude fiber so it

doesn't even contain all the lignin and

then we have a cellulose up here which

as far as nutrient value is very similar

to the cellulose so the van Souza system

came along several years ago to kind of

divide up this fiber more accurately so

now with the van SUSE method

have the ADF we have the India so the

NDF is going to contain cellulose all

the lignin and hemicellulose so in the f

is probably most often used to determine

intake the more in the EPI you have the

more fiber in the diet the kind of the

lower the intake there's just more

chewing time takes longer for the feast

us to pass through the digestive system

and in the F is also just a good measure

of how healthy we can keep that track as

well so even though you don't want maybe

a lot of fiber for most animals to keep

a healthy digestive tract you need a

little bit of fiber in the diet so from

balancing rations we don't want too much

fiber but we need a at least a small

amount of fiber so here we just have a

definition of NDF calculated it involves

a neutral detergent that dissolves

suppliant factors protein sugars lipids

their leaves behind the fibrous parts

such as cellulose lignin and in my

cereals and then if we take that in D F

and we further process it with a acid

detergent that will leave just the

cellulose and lignin which is the ADF

portion and that concludes the nutrition

by evaluation of foodstuffs it might be

time for a nap you guys have a good day