Quiz 3 Animal Nutrition UCM

lipids, carbs, protein

What nutrient rank provides the most energy?

• top one has 2.25 times more energy compared to carbohydrates and protein on a per weight basis

carbs, protein, lipids

What nutrient classes are the main source of energy in farm animal diets?

lipids are used in small amounts to still provide energy, but also prevent the feed to go rancid during storage since they easily break down feed

If lipids (i.e. fats and oils) are so high in energy, why aren’t lipids used as the primary energy source in farm animal diets?

oils are polyunsaturated fatty acids while animal fats are saturated

Difference between fats and oils

polyunsaturated have 2 carbons with dbl bonds while saturated doesnt have any

Polyunsaturated fatty acids have what compared to saturated fatty acids?

Fats = solid, oil = liquid

The difference between fats and oils is their physical state at room temperature (i.e. approximately 68-77°F) ?

long chain of carbons (4-28)

What is a fatty acid?

three fatty acids connected to a glycerol backbone

What is a triglyceride?

essential fatty acids are lipids that animals must consume in diet

What are EFAs?

because the body require them to live as a source of energy. since the body cant make them, they must be consumed

Why are EFAs essential?

linoleic, linolenic, arachidonic acid

What are three EFAs that are typically found in most plants making it easier for livestock producers?

carbs are formed from a combo of CO2, water, and sunlight during photosynthesis

How are carbohydrates (CHO) formed?

carbon, hydrogen, oxygen

What are carbohydrates made of?

draw

Draw glucose molecule and label C

one CHO molecule

What is a monosaccharide made of?

two CHO molecule

What is a disaccharide made of?

more than two CHO molecule

What is a polysaccharide made of?

glucose

Example of monosaccharide

maltose

Example of disaccharide

starch

Example of polysaccharide

polysaccharide chain of glucose molecules used as energy by the plants

What is starch?

as glucose stored in the plant primarily in the seed for a highly digestible energy source

Where do we find starch?

blood sugar

What is glucose also referred too?

6 carbons, 1 oxygen, 1 OH

How many carbons does glucose have?

Through alpha 1, 4 bond

Where in starch does the glucose molecules connect?

polysaccharide chains that contain glucose that are lowly digestible carbs

What are cellulose and hemicellulose?

in stems and leaves of plants (structural carbs) where they are consumed and used as energy

Where are cellulose and hemicellulose found?

straight chain of glucose molecules

What does cellulose look like in conformation?

randomly branched chain of different CHO molecules

What does hemicellulose look like in conformation?

they provide the plant’s stems and leaves structural integrity so they can grow vertically

What purpose does the different conformations of hemicellulose and cellulose serve?

(amount of feedstuff * cost per pound * number of days in feeding period) / (ending weight - starting weight)

cost of the diet per pound of weight gain equation

FE = amount of feed fed for the feeding period / difference in weight for the feeding period

feed efficiency equation

ADG = ending weight - beginning weight / number of days in the time period

average daily gain equation

used by livestock producers to evaluate different feed diets for livestock to determine how that diet affected the weight gain of an animal

What is ADG used for in animal nutrition?

used to determine how many pounds of feed were needed to produce one pound of weight gain for one animal

Describe feed efficiency

(amount of hay* cost per pound * number of days in feeding period)+(amount of corn* cost per pound * number of days in feeding period) / (ending weight - starting weight)

Example of cost of diet per 1 lb of weight gain with multiple feedstuffs

it means the animal lost weight

What does a negative number mean when calculating FE or cost per 1 lb of weight gain?

beta 1, 4 bond (horizontal)

Where in cellulose does the glucose molecules connect?

beta 1, 4 or 1, 3 bonds

Where in hemicellulose does the glucose molecules connect?

vertical

Which way to do beta 1, 3 bonds form?

different types of bonds allow for branching structure in hemicellulose

Alpha bonds can only be broken by the enzyme amylase, which is primarily produced in the pancreas of the animal and by the microbes

Why are the bonds between the carbohydrate molecules in starch, cellulose and hemicellulose so important to understand regarding alpha bonds?

Beta bonds can only be broken by the enzyme cellulase which is only produced by the microbes during microbial digestion in the rumen and/or in the cecum

Why are the bonds between the carbohydrate molecules in starch, cellulose and hemicellulose so important to understand regarding beta bonds?

It shows why ruminant and HGF animal can benefit from forages compared to monogastrics (microbial digestion)

What can we understand through understanding bonds between the carbohydrate molecules in starch, cellulose and hemicellulose?

mechanical digestion, enzymatic digestion through amylase in saliva

How is starch digested in the mouth?

mechanical digestion, chemical digestion from HCl, no enzymatic digestion

How is starch digested in the stomach?

Through amylase, enzyme released from pancreas, which breaks starch into maltose

How is starch digested in the small intestine → duodenum?

Maltose is broken into 2 glucose molecules by maltase, sucrose is broken into glucose/fructose by sucrase, lactose is broken into glucose/galactose by lactase. individual glucose molecules can be absorbed

How is starch digested in the small intestine → duodenum on the surface of the villi?

only absorption of monosaccharides happens here into the blood stream since water soluble

How is starch digested in the small intestine → jejunum and ileum?

glucose, fructose, galactose

What monosaccharides (since they are water soluble nutrients) are mainly absorbed into the bloodstream then the liver?

As glucose enters the blood stream, the pancreas is triggered to release insulin. Insulin allows the cell to absorb glucose (like a key) without glucose can’t enter

How is glucose absorbed into the cell?

When glucose gets too low in the bloodstream, the hormone glucagon is released by the pancreas to stimulate the liver to release glucose from glucose reserves (glycogen)

How is glucose maintained in the bloodstream?

cellular metabolism of glucose is how the cell gets energy. The source of energy in the cell is adenosine triphosphate (ATP)

How is glucose metabolized by the cell to make energy?

temporary storage in long chains called glycogen, long term storage as fat

How is glucose metabolized by the cell for storage?

RNA and DNA backbone

How is glucose metabolized by the cell to make other cellular products?

Stage 1: glycolysis → Acetyl-CoA, Stage 2: Kreb’s cycle → NADH, FADH2 (reduced e- carriers), Stage 3: oxidative phosphorylation → ATP

Metabolism of glucose in the cell to produce energy in the form of adenosine triphosphate (ATP)

36-38

What is the total amount of ATP produced from one glucose molecule during the stages of cellular metabolism?

mechanical digestion, enzymatic digestion by the microbes through microbial digestion

How is starch digested in the rumen and cecum?

bacteria, protozoa, fungi

3 types of microbes in the rumen and cecum

hundreds of bacteria populate in anaerobic environment (little to no oxygen)

What has research show regarding bacteria in the rumen?

one that digests cellulose/hemicellulose from forages, and one that digests starch from grains

What are the two basic categories of bacteria?

If majority of diet is forages then mainly forage digesting bacteria will be present. Vice versa for grain

How does the proportion of two different bacteria change depending on diet?

10-14 days to allow for microbial population to adapt

In what period of time should a ruminant diet be changed?

6 to 6.4

What is the normal pH of the rumen?

The pH drops to 6, if drops lower than the forage bacteria will stop functioning but the starch bacteria continues. The starch digesting bacteria produces excess lactic acid which can cause lactic acidosis

What can happen with a ruminant is consuming a grain based diet?

bicarbonate

What helps maintain the pH of the rumen from the saliva?

Always contain some forages even in a high grain diet

What can we do to prevent decline in feed intake from lactic acidosis?

acetate, propionate, butyrate

What are the 3 VFAs produced in the rumen during microbial digestion?

produced from the digestion of starch, cellulose, and hemicellulose

How are VFAs produced?

microbes break apart polysaccharide chains into individual glucose molecules using enzymes amylase and cellulase

What is first happens in microbial digestion regarding polysaccharide chains?

microbes use glucose molecules as energy

What is the second step in microbial digestion glucose?