You need to supply 50g of lysine to a pig, using a supplement that contains 25% D.L-lysine. How much of this supplement should you feed?

1. 50g

2. 25g

3. 200 g

4. 400g

5. 12.5g

0.25g D,L-lys/g feed X 0.5g L/g D,L x? = 50g

0.25g D,L/g feed x? = 100g

? = 400g

4. 400g

Phenylalanine

Valine

Threonine

Tryptophan

Isoleucine

Methionine

Histidine

Arginine

Leucine

Lysine

If phenylalanine can be used to meet the tryptophan requirement, is tryptophan really an essential nutrient?

1. Yes

2. No

3. Well, sort of, these things are complicated! The body wouldn't be able to make enough unless Phe is fed in excess, and is that really a normal situation? I mean come on!

1. Yes

2. No

3. Well, sort of, these things are complicated! The body wouldn't be able to make enough unless Phe is fed in excess, and is that really a normal situation? I mean come on!

in PVT TIM HALL, so yes :)

Why might arginine become less essential as an animal ages?

1. The body's ability to synthesize arg improves

2. Adults no longer need arg

3. Other amino acids can be used in place of arg during protein synthesis

1. The body's ability to synthesize arg improves

-the liver can change its functionality

-arginine is always needed otherwise your body wouldn't function properly

-cannot be replaced-needs to be found in diet

What chemical property is used to measure the protein content of a feed?

1. Water solubility

2. Combustion

3. N content

4. Double bonds

3. N content

proteins contain Nitrogen

-exspensive

-allows nutritionists to meet essential amino acid needs of the animal

Which of these amino acids would be most limiting?

AA                Requirement    Supply

Histidine           0.15%          0.2%

Lysine              0.8%            0.25%

Methionine       0.4%            0.25%

1. Histidine

2. Lysine

3. Methionine

4. Lysine and methionine are equally limiting

supply/requirement = % required

2. Lysine

     Gross Energy

--------------------------------> Fecal Energy

     Digestible Energy

--------------------------------> Urine and Gas Energy

     Metabolizable Energy

--------------------------------> HI (digestion &

                                        fermentation Energy)

     Net Energy

NEm             NEg

                               N consumed

(Digestibility)----------------------> Fecal N

                               N Digested

(BV)----------------------------------> Urine N

(N retention-> & ^) N Retained

-----------------------------------------> Inedible body

                                                       protein (hair,

                                                       blood, etc)

                                N in edible product

                                (meat, milk, eggs)

N digestion % = [N absorbed/N comsumed] X 100

or

[N intake - fecal N/N intake] X 100

BV% = [N retained/N absorbed] X 100

or

[N intake - fecal N - urine N/N intake - fecal N] X 100

Which of the following factors would determine the biological value of a protein?

1. Digestibility of the protein

2. Amino acid composition

3. Tertiary structure of the protein

4. How much energy was consumed with it

-if retained, it meets the needs of the animal

-high protein meets amino acid needs well

2. Amino acid composition

N retention % = [N retained/N concumed] X 100

or

[N intake - fecal N - urine N/N intake] X 100

or

N digestibility X BV

What is the % nitrogen retention for turkeys consuming 16g of CP per day and adding 8g of muscle protein?

1. 50%

2. 8%

3. 200%

4. 24%

8/16 = 50%

1. 50%

One could be sure to meet amino acid requirements just by feeding extremely high CP diets. What's the problem with this approach?

1. It's expenseive

2. It wastes a lot of protein

3. A lot of N ends up in the manure and has to be disposed of

4. All of the above

4. All of the above

-higher N efficiency, less N waste and less potential for pollution

-lower cost

-begins in stomach with pepsin

-cont. to duodenum with pancreatic proteases

-enzymes along intestinal brush border complete the job

In a pig, what nutrient(s) are digested in the stomach?

1. Carbohydrates

2. Lipids

3. Proteins

4. All of the above

3. Proteins

-components of proteins

-energy source

-glucose precursor

-fatty acid precursor

these are dependent on: condensation (protein synthesis), deamination, and transamination

If your body is short on one non-essential amino acid but has plenty of another, what reaction can be used to create more of the limited one?

1. Deamination

2. Urea synthesis

3. Transamination

4. Gluconeogenesis

3. Transamination

When would the most urea be produced?

1. When excess protein is fed

2. When dietary protein id low

3. When the amino acid profile of the diet is carefully balanced

4. When body protein synthesis is high

1. When excess protein is fed

-usually urea

-converted to NH₃ in the rumen, then used by bacteria to create amino acids

-many proteins are cleaved and amino acids are broken down by microbes

-some protein is difficult to digest without acid

DNA

RNA

Protein

Function

-found in nucleus and cytoplasm

-mRNA: messenger RNA, encode genes

-tRNA: transfer RNA, delivers amino acids

If an animal has one normal copy and one mutated copy of a gene, can a normal protein be produced?

1. Yes

2. No

3. No protein is produced at all

1. Yes

If some tRNA became depleted in a cell, which

process(es) would stop?

1. Transcription

2. Translation

3. Protein folding

4. Protein transport

tRNA carries amino acids

2. Translation

Which nutrient is under tight homeostatic control in the bloodstream?

1. Free fatty acids

2. Glucose

3. Chylomicrons

4. Leucine

can get glucose from amino acids

2. Glucose

can be controlled by altering:

1. transcription of genes

2. translation of proteins

3. activity of proteins (protein modification)

4. cellular location of proteins

5. degredation of proteins

Enzymes often have a phosphate group added to them. This is an example of regulation by:

1. Altered transcription

2. Altered translation

3. Altered protein activity

4. Relocation of protein in the cell

3. Altered protein activity

-acts to decrease blood glucose after meals

-acts on liver, muscle, and adipose tissue

-causes increased transcription of glucose transporter

-moves glucose transporter to the cell membrane

-activates enzyme that synthesizes glycogen

-de-activates glycogen's catabolic enzyme

-glucose utilization

-LPL release to bring in fatty acids

-increases transcription of enzymes involved in lipogenesis

-activates lipogenic enzymes

1. insulin

2. insulin receptor

3. glucose transporter-4

4. glycogen

Across tissues, what mechanism(s) does insulin use to regulate glucose metabolism?

1. Altered transcription

2. Change in cellular location of proteins

3. Change in protein activity

4. All of the above

4. All of the above

-released when blood glucose is low

-counteracts most effects of insulin

-released by pituitary gland

-stimulate mobilization of body fat

-stimulates secretion of insulin-like growth factor 1 (IGF-1)

-important during growth lactation

What is one common consequence of a hyperactive thyroid gland?

1. Low body temperature

2. Lack of appetite

3. High blood glucose

4. Difficulty in storing fat

4. Difficulty in storing fat

-Calcium

-Phosphorus

-Sodium

-Chlorine

-Potassium

-Magnesium

-Sulfur

-skeleton and teeth 99%

-nerve signal transmission

-muscle contraction

-blood clotting

-low blood Ca concentration triggers parathyroid gland to secrete parathyroid hormone (PTH)

-PTH stimulates kidneys to retain Ca and produce active vitamin D

-Vitamin D causes increased absorption of Ca from the gut. Ca reabsorption from the bone is also stimulated.

How do the kidneys influence blood Ca?

1. They store Ca

2. They send signals to bone to release Ca

3. They alter the rate of Ca excretion in blood

4. They have no influence at all

3. They alter the rate of Ca excretion in blood

-increase in dietary concentration, increase in total amount absorbed

-increase in dietary concentration, decrease in % absorbed

If an animal has low vitamin D but is fed a high Ca diet:

1. Absorption will be passive transport

2. Ca will not be absorbed

3. Calcium binding protein will absorb Ca

4. PTH will stimulate active transport

 1. Absorption will be passive transport

young:

 rickets - failure of cartilage to ossify (stay soft)

adult:

osteomalacia - decreased mineral content of bone and increased nonmineralized matrix

osteoprosis - greater osteoclast activity leads to bone weakening

-low blood Ca

-inability to move due to inadequate calcium to allow for muscle contraction

-excess Ca limits absorption of other minerals

-can cause skeletal abnormalities in growing dogs

-80% skeleton

-20% soft tissue

-non-ruminants about 1/3 of the phosphorus in grain is digested and utilized

-2/3 phosphorus is in the form of phytate phosphorus

-enzyme produced by ruminal microbes

-can be added to nonruminant diets to release P from phytate

When added to a swine diet, where does phytase do most of its work?

1. In the stomach

2. In the small intestine

3. In the large intestine

4. In the feed prior to the animal eating it

4. In the feed prior to the animal eating it

-causes rickets and other disorders like Ca

-pica: appetite for non-nutritive objects (dirt, wood, etc.)

-"big head disease"

-distorted snout

-P is controlled by PTH and vitamin D

-bone contains most P

If a farm has a problem with zinc deficiency, but is feeding plenty of zinc, the most likely reason is:

1. The animals are missing the zinc transporter

2. Another mineral fed in excess is preventing zinc absorption

3. The feed contains a zinc-binding agent

4. the water contains inadequate zinc

2. Another mineral fed in excess is preventing zinc absorption

-calcifies (hardens) soft tissues

-skeletal deformities (soft bones)

What is a problem with providing a Mg supplement for grazing cattle?

1. Some animals eat little, others too much

2. You can't provide enough to meet requirements

3. There is no way to get them to consume it

4. It is too unstable in a pasture setting

1. Some animals eat little, others too much

If extracellular Cl^- drops very low, what might happen to cells?

1. Nothing, Cl is outside the cells anyway

2. The cells could shrivel

3. Cells could have to pull in more ions

4. The cells could burst

4. The cells could burst

Which diet might require supplemental sulfur?

1. Mixed grasses being consumed bby a horse

2. A corn/soybean diet fed to pigs

3. A meat-based diet for a dog

4. A feedlot diet for a steer

1. Mixed grasses being consumed bby a horse

-excessive amounts

-water levels can cause a problem

-ethanol plants --> byproducts fed to livestock

-head turns back and upwards

-blindness

-instability to stand

-eventually coma....and most times death

You are concerned about S in your distillers grains. What can you do to prevent PEM?

1. Remove inorganic S from diet

2. Test water sources for S concentration

3. Monitor S content in distillers sources

4. All of the above

4. All of the above