Protein: Ruminant Digestion And Absorption

Question 1

Do ruminants have proteases?

Answer 1

NO

Question 2

What is responsible for protein digestion in ruminants?

Answer 2

Microbes

Question 3

Where do ruminants obtain nitrogen from?

Answer 3

Feed and endogenous sources

Question 4

In ruminants, crude protein can be divided in to what 2 categories?

Answer 4

Dietary protein and NPN

Question 5

What is the main component of dietary protein from which ruminants obtain their N?

Answer 5

Amino acids

Question 6

The 2 categories of protein obtained from dietary protein are:

Answer 6

RUP and RDP

Question 7

RDP gets converted into what?

Answer 7

Amino acids and eventually microbial protein

Question 8

RUP is digested in the small intestine by what?

Answer 8

Proteolytic enzymes

Question 9

The dietary NPN is just a source of N not form aa what turns it into NH 3?

Answer 9

Urease

Question 10

What do microbes do with the N from NPN?

Answer 10

They produce NH3 with ATP

Question 11

Why is it important to coordinate carbohydrate fermentation patterns with protein degradation patterns?

Answer 11

Because both patterns dictate the synthesis of microbial protein

Question 12

How can we convert feed into RUP?

Answer 12

By treating it with heat or chemicals

Question 13

What are some factors that affect degradation of proteins?

Answer 13

Chemical nature, physical barriers, feed intake, feed processing

Question 14

The three proteins factions based on solubility are?

Answer 14

A B C

Question 15

Microbes digest protein into what three things?

Answer 15

Amino acids, NH3, VFAs

Question 16

Why is microbial proteins of high biological value?

Answer 16

Because it matches the composition of amino acids that’s needed by muscles or milk

Question 17

Synthesis of microbial protein is dependent on what?

Answer 17

Availability of nitrogen, carbohydrate fermentation, amount of energy available

Question 18

Ammonia is used by the rumen in what ways?

Answer 18

To synthesize new protein, or it is absorbed to make urea

Question 19

If there is an energy shortage and ammonia becomes excessive in the rumen and what happens to it?

Answer 19

Ammonia goes to the liver and it’s converted into urea where it is either recycled or excreted

Question 20

Why would nitrogen never build up in the rumen?

Answer 20

Because urease would continuously be converting it into ammonia or CO2

Question 21

Urea from the liver is continuously degraded into what?

Answer 21

NH3

Question 22

What are the three ways that blood urea is distributed In the body?

Answer 22

It is either excreted into urine, taken up into milk or recycled back into the rumen and or saliva