Tom Jenkins, Professor Department of Animal & Veterinary Sciences Rumen Transformation s of Lipid
Mar 30, 2015
Tom Jenkins, ProfessorDepartment of Animal &Veterinary Sciences
Rumen Transformations of Lipid
Rumen Transformations of LipidReview of Dietary Lipid
Fatty acids are most important lipid fraction.
Majority of fatty acids are bound to glycerol as simple or compound lipids.
Majority of fatty acids are unsaturated.
Rumen Transformations of LipidLearning Objectives
What happens to dietary lipid as it passes from the diet to the intestines and is metabolized by rumen microorganisms?
What are the intermediates and end products that accumulate in the rumen from lipid metabolism?
How does lipid transformations in the rumen affect animal performance?
Rumen Transformations of LipidCompounds Extracted in Fat Test?
Biohydrogenation
Compound
Simple
Lipolysis
MUFA
PUFA
Microbial Lipid Synthesis VFA
Rumen Transformations of LipidHow Does Dietary Lipid Changeas it Passes Through the Rumen?
47.9 lb. DMI60% Forage(mainly corn silage,5 lbs. alfalfa hay)
From CPM for Dairy v.3.0.8
Intake
892 g FA(<10%
FFA)
2 g C18:0
219 g C18:1
440 g C18:2
37 g C18:3
Rumen Transformations of LipidRumen FA Transformations
Outflow
876 g FA
C18:0
C18:1
C18:2
C18:3
From CPM for Dairy v.3.0.8
LargeIntestine
SmallIntestine
Rumen
Omasum
Abomasum
Reticulum
Esophagus
Rumen
CH
H H H H H H H H H H H H H H H H H
C C C C C C C C C C C C C C C C C
H H H H H H H H H H H H H
O
OH
Rumen Transformations of LipidBiohydrogenation
Unsaturated (18:2)
Stearic (18:0)
Rumen Transformations of LipidBiohydrogenation
Unsaturated Fat
H
C
H
C
H H
H
C
H
H
C
H
C
Rumen Transformations of LipidBiohydrogenation
H
C
H
C
H H
H
C
H
H
C
H
C
H H
Rumen Transformations of LipidBiohydrogenation
Saturated Fat
H
C
H
C
H H
H
C
H
H
C
H
C
H H
Rumen Transformations of LipidBiohydrogenation
Unsaturated (18:2)
CLA (18:2)
trans (18:1)
Stearic (18:0)
Rumen Transformations of LipidBiohydrogenation
Unsaturated Fat
H
C
H
C
H
C
H
H
C
H
C
Rumen Transformations of LipidBiohydrogenation
H
C
H
C
H
H
C
H
H
C
H
C
Rumen Transformations of LipidBiohydrogenation
H
C
H
C
H
C
H
H
C
H
C
CLA
Rumen Transformations of LipidCLA Intermediates in Digesta
Linoleic (18:2)
cis–9 trans–11 (18:2)
trans–11 (18:1)
Stearic (18:0)
From Teter, B.B., and T.C. Jenkins. 2006. In Advances in Conjugated Linoleic Acid Research, Vol. 3
t7t9 t8t10 t9t11 t10t12 t11t13 t12t140
102030405060
% of total
t7c9 t8c10 c9t11 t10c12 t11c13 c11t13 c12t140
20
40
60
80
100
Rumen Transformations of LipidPoint 1–Diet Can Change BH
Linoleic Acid (cis–9, cis–12 C18:2)
Conjugated Linoleic Acid(cis–9, trans–11 CLA)
trans–11 C18:1
Stearic (C18:0)
Conjugated Linoleic Acid Isomers
trans–C18:1 Isomers
Stearic (C18:0)
Altered Pathways
Rumen Transformations of LipidPoint 2
MINOR intermediates of biohydrogenation can have MAJOR effects on animal performance and human health
Rumen Transformations of LipidImpact of Rumen Lipid Metabolism
Affects human health Meat and milk higher in saturated fat Bioactive metabolites
Anti-carcinogenic Anti-atherogenic Enhance immune system
Rumen Transformations of LipidImpact of Rumen Lipid Metabolism
Affects animal performance Supply of essential fatty acids– reproduction Fatty acid antimicrobial effects– production Bioactive metabolites
Milk fat depression
Rumen Transformations of LipidQuestion
Match each of the below from the list of answers shown on the right. One answer per blank.
1. ___ Abbreviation of the major fatty acid consumed by dairy cows
2. ___ Increases FFA in rumen contents
3. ___ Abbreviation of the CLA normally produced in the rumen
4. ___ Greatly reduces the supply of essential fatty acids to body tissues
A.BiohydrogenationB.cis–9, trans–11 18:2C.LipolysisD.cis–9, cis–12 18:2E. trans–11 C18:1F. Peroxidation
Rumen Transformations of LipidQuestion
Which of the below is the best substrate for the synthesis of CLA in the rumen?A. Omega–9 fatty acidsB. Essential fatty acidsC. Saturated fatty acidsD. None of the above
Rumen Transformations of LipidQuestions & Answers
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