A11

Question 1

What is fermentation of carbohydrates?

Answer 1

It is the process where rumen microroganisms is used to produce energy

Question 2

What breaks down the carbohydrates?

Answer 2

Microbes

Question 3

what does the microbes in the rumen include?

Answer 3

Bacteria, fungi and protozooa

Question 4

What does the microbes feed on?

Answer 4

The forages ingested by the cow

Question 5

How are the carbohydrates fermented?

Answer 5

The microbes break the carbohydrates down to simpler sugars. These sugars are used as an energy source for growth and to make the end product

Question 6

What is the end product of carbohydrate fermentation?

Answer 6

VAF = Volatile Fatty Acid¨

Question 7

What is VAF?

Answer 7

The primary energy source of ruminants

Question 8

What is the optimal pH in the rumen?

Answer 8

6.2-6.8

Question 9

What happens if the pH is decreased?

Answer 9

Less than 6. fibre-digesting bacteria die out, lactic acid bacteria increase, and acidosis results

Question 10

How does saliva play a role?

Answer 10

It acts as a buffer. The saliva will improve the rumination capacity and the activity of the bacterias will be much better.

Question 11

How much saliva is produced?

Answer 11

20L/day

Question 12

How much of the energy supply is based on the VFAs?

Answer 12

70-80%

Question 13

Name the major Volatile Fatty Acids produced:

Answer 13

1. acetate (or acetic acid)
2. propionate (or propionic acid)
3. butyrate (or butyric acid)

Question 14

How are the VFA absorbed?

Answer 14

through the walls of the rumen and are then
transported in the blood to the liver. In the liver they are converted to other sources of
energy. From the liver, the energy produced is used to perform various functions

1. Milk production
2. Pregnancy
3. Growht

etc

Question 15

Name the main composition and types of carb in plants

Answer 15

Non-structural and structural carbs

Question 16

Name some non structural carbs

Answer 16

Starch and sugar

Question 17

Name some structural carbs

Answer 17

Hay/roughage, pectin, cellulose, hemicellulose, lignin

Question 18

What is the main goal of fermentation of carbohydrates?

Answer 18

To produce pyruvate from carbohydrates, such as sugar, starch, cellulose etc to the volatile fatty acids - Energy source

Question 19

What does the bacteria produce in the rumen?

Answer 19

Extracellular enzymez, which break down the polysaccharides down to pyruvic acid

Question 20

What happens to the produced pyruvic acid?

Answer 20

Enters into 4 different pathways and is then broken down by the INTRACELLULAR ENZYMES to produce either VFA or ATP

Question 21

How much Volatile Fatty Acids i produced per day?

Answer 21

3-5kg/day

Question 22

What happens if the starch concentrate decreases and the hay content increases?

Answer 22

Acetic acid levels increase and propionic levles decreases

Question 23

increased fibre = ?

Answer 23

increased lactic acid

Question 24

increased starch =?

Answer 24

increased propionic levels

Question 25

What happens if the formic acid is conversed into methane?

Answer 25

Significant energy loss, up to 8-10%