EFFECT OF OMEGA-3 FATTY ACIDS ON THE OVARIES OF LACTATING DAIRY COWS

145 Pages·2011·1.14 MB·English

by  Mallikarjun Bidarimath

EFFECT OFOMEGA-3FATTYACIDSONTHEOVARIESOFLACTATING
DAIRYCOWS
by
MallikarjunBidarimath
Submittedinpartialfulfilmentoftherequirements
forthedegreeofMasterofScience
at
DalhousieUniversity
Halifax,NovaScotia
inco-operationwith
NovaScotiaAgriculturalCollege
Truro,NovaScotia
December2011
©CopyrightbyMallikarjunBidarimath,2011
DALHOUSIEUNIVERSITY
NOVA SCOTIAAGRICULTURALCOLLEGE
The undersigned hereby certify that they have read and recommend to the Faculty of
Graduate Studies for acceptance a thesis entitled “EFFECT OF OMEGA-3 FATTY
ACIDS ON THE OVARIES OF LACTATING DAIRY COWS” by Mallikarjun
Bidarimathinpartialfulfillmentoftherequirements forthedegreeofMasterofScience.
Dated:December6,2011
ExternalExaminer: _________________________
Co-Supervisors: _________________________
_________________________
Readers: _________________________
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ii
DALHOUSIEUNIVERSITY
AND
NOVA SCOTIAAGRICULTURALCOLLEGE
DATE: December6,2011
AUTHOR: MallikarjunBidarimath
TITLE: EFFECT OFOMEGA-3FATTYACIDSONTHEOVARIESOF
LACTATINGDAIRY COWS
DEPARTMENTOR SCHOOL: Departmentof Plantand AnimalSciences
DEGREE: MSc CONVOCATION: October YEAR: 2012
Permission is herewith granted to Dalhousie University to circulate and to have copied
for non-commercial purposes, at its discretion, the above title upon the request of
individuals or institutions. I understand that my thesis will be electronically available to
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The author reserves other publication rights, and neither the thesis nor extensive extracts
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The author attests that permission has been obtained for the use of any copyrighted
material appearing in the thesis (other than the brief excerpts requiring only proper
acknowledgementinscholarlywriting), andthatallsuchuseisclearlyacknowledged.
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iii
TableofContents
LISTOFTABLES……………………………………………………………………...vii
LISTOFFIGURES…………………………………………………………………..….x
ABSTRACT……………………………………………………………………………xiii
LISTOFABBREVIATIONSANDSYMBOLSUSED……………………………..xiv
ACKNOWLEDGEMENTS………….………………………………………………..xvi
CHAPTER1:INTRODUCTION.....................................................................................1
CHAPTER2:LITERATUREREVIEW........................................................................5
2.1EstrousCyclicityinBovines...................................................................................5
2.1.1EstrousCycle......................................................................................................5
2.1.2OvarianFollicularDynamics duringBovineEstrousCycle............................7
2.1.2.1Pre-antral FollicularPopulation.......................................................................7
2.1.2.2 Follicular Waves duringEstrousCycle...........................................................9
2.1.2.3Recruitmentofa Cohortof Follicles.............................................................10
2.1.2.4Selection........................................................................................................11
2.1.2.5CharacteristicFeaturesoftheDominant Follicle..........................................11
2.1.2.6 Final MaturationofPreovulatoryFollicle.....................................................13
2.1.2.7OvulationofthePreovulatoryFollicle..........................................................14
2.1.3OvarianLutealDynamics duringBovine EstrousCycle................................15
2.1.3.1 Luteinization,Development andMaintenanceofCL...................................15
2.1.3.2BiosynthesisofProgesterone.........................................................................16
2.1.3.3Regression(Luteolysis)ofCL.......................................................................17
2.1.4HormonalInterplayControllingBovine EstrousCycle.................................19
2.1.4.1Gonadotropin-ReleasingHormone................................................................20
2.1.4.2Profilesof FSHand LHduringtheEstrous Cycle........................................21
2.1.4.3Estradiol-17(cid:533)(E )Profile..............................................................................23
2
2.1.4.4Progesterone(P ) Profile...............................................................................24
4
2.1.4.5Prostaglandin F Profile...............................................................................25
2(cid:302)
2.2PresynchandOvsynchProtocol..........................................................................26
iv
2.3FattyAcidClassificationandBackgroundInformation...................................27
2.3.1Classificationof LongChain Polyunsaturated FattyAcids..............................28
2.3.2DietaryOmega-3 FattyAcidSources of PlantOrigin......................................30
2.3.3DietaryOmega-3 FattyAcidSources of MarineOrigin..................................31
2.3.4Biosyntheticand MetabolicPathwaysofOmega-3 FattyAcids......................33
2.4FatSupplementationandReproductivePerformance......................................35
2.5Feeding SystemandReproductivePerformance...............................................41
CHAPTER3:OBJECTIVES.........................................................................................45
CHAPTER 4: OVARIAN DYNAMICS AND PROGESTERONE PROFILES IN
LACTATING DAIRY COWS SUPPLEMENTED WITH OMEGA-3 FATTY
ACIDSDURINGCONVENTIONAL ESTRUSANDOVSYNCHPERIOD............46
4.1ABSTRACT........................................................................................................46
4.2INTRODUCTION...............................................................................................47
4.3MATERIALSAND METHODS........................................................................52
4.3.1ExperimentalDesign,Animals, Feedingand Housing.....................................52
4.3.2Analysisof Feed...............................................................................................55
4.3.3Synchronizationof Estrus andOvulation.........................................................55
4.3.4MilkSamplingand Analysis............................................................................56
4.3.5BloodSamplingandProcessing.......................................................................57
4.3.6Analysisof FattyAcids....................................................................................57
4.3.7UltrasoundTechnique.......................................................................................58
4.3.8 FollicularDataAnalysis...................................................................................58
4.3.9 LutealDataAnalysis........................................................................................59
4.3.10ProgesteroneHormoneAssays.......................................................................60
4.3.11StatisticalAnalyses.........................................................................................63
4.4RESULTS............................................................................................................66
4.4.1 FeedComposition.............................................................................................66
4.4.2MilkYieldandComposition............................................................................71
4.4.3PostpartumCyclicityandEstrusResponses.....................................................73
4.4.4 FollicularDynamics inPastureGroup.............................................................75
4.4.5 LutealDynamicsin PastureGroup...................................................................81
v
4.4.6Progesterone Profiles........................................................................................86
4.4.6.1During&After Presynch Period...................................................................86
4.4.6.2During&AfterOvsynch Period....................................................................90
4.5DISCUSSION....................................................................................................100
CHAPTER5:CONCLUSIONS...................................................................................110
5.1Conclusions.......................................................................................................110
5.2 FutureRecommendations..................................................................................110
5.2.1HormonalProfiles...........................................................................................111
5.2.2CholesterolEstimationand FattyAcid ProfilingofOocytes.........................111
5.2.3GeneandReceptorExpressionStudies..........................................................112
REFERENCES..........................................................................................................113
vi
LISTOFTABLES
Table4.1 Ingredient composition of the high lactation total mixed ration (TMR)
and concentrate fed to the lactating dairy cows during the feeding trail
(Source:PayamVahmani,PersonalCommunication)..................................67
Table4.2 Chemical composition of the pasture fed to the lactating dairy cows
during the feeding trial (Source: Payam Vahmani, Personal
Communication)...........................................................................................67
Table4.3 Chemical composition of the silage fed to the lactating dairy cows
during the feeding trial (Source: Payam Vahmani, Personal
Communication)...........................................................................................68
Table4.4 Chemical composition of the concentrate mix (% DM basis) fed to the
lactating dairy cows during the feeding trial (Source: Payam Vahmani,
PersonalCommunication).............................................................................68
Table4.5 Chemical composition of the high lactation total mixed ration (TMR)
diet and mineral and vitamin supplement fed to the lactatingdairycows
managed in confinement during the feeding trial (Source: Payam
Vahmani,PersonalCommunication)............................................................69
Table4.6 Fatty acid composition of the rumen-protected marine algae (RPMA)
and rumen-protected fish oil (RPFO) supplemented to lactating dairy
cows managed either on pasture or in confinement during the feeding
trial(Source:PayamVahmani,PersonalCommunication)..........................70
Table4.7 Mean daily number of the large follicles ((cid:149)10 mm) in lactating dairy
cows managed on pasture and fed control diet (no lipid supplement),
rumen-protected fish oil (RPFO), or rumen-protected marine algae
(RPMA)duringandafterthePresynchperiod.............................................75
Table4.8 Mean daily diameter of the large follicle ((cid:149)10 mm) in lactating dairy
cows managed on pasture and fed control diet (no lipid supplement),
rumen-protected fish oil (RPFO), or rumen-protected marine algae
(RPMA)duringtheOvsynchperiod.............................................................79
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Table4.9 The number of CLs at each injection in lactating dairy cows managed
on pasture and fed control diet (no lipid supplement), rumen-protected
fish oil (RPFO), or rumen-protected marine algae (RPMA) during
conventionalestrus and Ovsynchperiod......................................................82
Table4.10 The diameter of the CL (mm) in lactating dairy cows managed on
pasture and fed control diet (no lipid supplement), rumen-protected fish
oil (RPFO), or rumen-protected marine algae (RPMA) during the
period between the 1st GnRH (Day 0) to 3rd PGF injection (Day 7) of
2(cid:302)
theOvsynchperiod.......................................................................................84
Table4.11 The diameter of the CL (mm) in lactating dairy cows managed on
pasture and fed control diet (no lipid supplement), rumen-protected fish
oil (RPFO), or rumen-protected marine algae (RPMA) during the
period between the 1st GnRH (Day 0) to 2nd GnRH injection (Day 9.5)
oftheOvsynchprotocol................................................................................85
Table4.12 Plasma progesterone (ng/mL) concentrations in lactating dairy cows
managed either on pasture or in confinement and fed control diet (no
lipid supplement), rumen-protected fish oil(RPFO), or rumen-protected
marine algae (RPMA) during the period between the 1st PGF (Day 0)
2(cid:302)
to2ndPGF injections(Day11)ofthePresynch period..............................87
2(cid:302)
Table4.13 Plasma progesterone (ng/mL) concentrations in lactating dairy cows
managed either on pasture or in confinement and fed control diet (no
lipid supplement), rumen-protected fish oil(RPFO), or rumen-protected
marine algae (RPMA) during the period between the 2nd PGF (Day 0)
2(cid:302)
to1stGnRHinjections(Day11)afterthePresynchperiod..........................89
Table4.14 Plasma progesterone (ng/mL) concentrations in lactating dairy cows
managed either on pasture or in confinement and fed control diet (no
lipid supplement), rumen-protected fish oil(RPFO), or rumen-protected
marine algae (RPMA) during the period between the 1st GnRH (Day 0)
to3rd PGF injection(Day7)oftheOvsynchperiod..................................91
2(cid:302)
Table4.15 Plasma progesterone (ng/mL) concentrations in lactating dairy cows
managed either on pasture or in confinement and fed control diet (no
lipid supplement), rumen-protected fish oil(RPFO), or rumen-protected
marine algae (RPMA) during the period between the 2nd GnRH
injection of the Ovsynch (Day 0) to end of the experimental (Day 11)
period............................................................................................................96
viii
Table4.16 Plasma progesterone (ng/mL) concentrations in lactating dairy cows
managed either on pasture or in confinement feeding system (FS) and
fed control diet (no lipid supplement), rumen-protected fish oil(RPFO),
or rumen-protected marine algae (RPMA) lipid supplements (LS)
duringthePresynchand Ovsynchperiod.....................................................99
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LIST OFFIGURES
Figure2.1 Suggested pattern of follicular wave dynamics and pituitary
gonadotropin profiles during the two and three wave patterns of estrous
cycleincattle(Source:Adams et al.2008)....................................................8
Figure2.2 Reproductive hormonal profiles correlated with ovarian follicular and
luteal development during the estrous cycle of dairy cattle (Source:
MooreandThatcher2006)............................................................................19
Figure2.3 Biosynthetic desaturation and elongation pathways of omega-3 and
omega-6polyunsaturated fattyacids (Source:Mattosetal.2000)...............34
Figure2.4 Suggested mechanism of action by which LCPUFAs may improve
reproductiveperformanceindairycattle(Source: Staplesetal.1998)........36
Figure4.1 Ovulation presynchronization (Presynch) and synchronization
(Ovsynch) protocols Source: Pursley et al. (1995) and Moore and
Thatcher (2006).............................................................................................56
Figure4.2 Milk fat (%) of lactating dairy cows fed control diet (no lipid
supplement), rumen-protected fish oil (RPFO), or rumen-protected
marinealgae(RPMA)duringtheOvsynchperiod.......................................72
Figure4.3 Duration of estrus (d) in lactatingdairycows managed eitheron pasture
or in confinement after the 1st PGF injection during the Presynch
2(cid:302)
period............................................................................................................74
Figure4.4 Duration of estrus (d) in lactatingdairycows managed eitheron pasture
or in confinement after the 2nd PGF injection during the Presynch
2(cid:302)
period............................................................................................................74
Figure4.5 Mean daily number of the large follicles ((cid:149) 10 mm) in lactating dairy
cows managed on pasture and fed control diet (no lipid supplement),
rumen-protected fish oil (RPFO), or rumen-protected marine algae
(RPMA) during the period between the 1st GnRH (Day 0) to 2nd GnRH
injection(Day9.5)oftheOvsynchperiod....................................................76
x