Applied Digestive physio of Ru 3: Degradation and synth of fats in the rumen, dietary fat supplememtation

Question 1

Ether extract

Answer 1

Low amount in feed- only 2-2.5% DM

this equates to 25g/kg of DM

Question 2

Lipids, enzymes working on them and endproducts

Answer 2

The lipids: triglyceride, phospholipid and galactolipid

Worked on by bacterial lipase- hydrolysis takes places

Endproducts: FFA’s and Glycerol and galactose

Question 3

What is the glycerol and galactose converted to and what is unque about it

Answer 3

They are converted to VFAs that are unsaturated!

They become saturated in the rumen due to high conc of H+ ions

e.g linoleic acid and H+ becomes stearic acid

Question 4

Lipid nutrition in hihg yielding dairy cows

Answer 4

When dairy cow. requires more E- there is a tendency to give more conc BUT this decr chewing hence decr the amount of alkaline saliva (and it’s buffering capacity) leading to an incr VFA prod and ACIDOSIS

Question 5

What is an alternative feeding strategy to combat the acidosis caused by feeding concentrates

Answer 5

Give more fats (5-8% DM)

BUT veg fats dissolve and surriund fibres in the rumen- meaning that they cannot be digested by microbes and enzymes leading to a DECR of acetate

Question 6

What is a solution to the decreased acetate caused by fats surrounding the fibres

Answer 6

Aim to decr the lipids solubility:

1. Use hydrogenated oils
2. Ca/K salts or FA’s
3. Capping- surrounding the oil with protein

Question 7

Feed additives to mention here

Answer 7

Yeast culture

Buffers

Question 8

Yeast culture

Answer 8

Aspergillus orysil

Saccharomyces cerviciae

In high yielding dairy- post partum there is subopt rumen ferm

Yeast uses up O2 (and so decr it) providing an anaerobic environment for the ferm to take place

Question 9

Buffers

Answer 9

To maintain the pH at 6.2-6.8

Give NaHCO3

Question 10

Talk about the dailt food and water supply

Answer 10

Needs to eat 2-3% DM of her BW

Needs to drink up to 100-200L of water a day