Lecture 2 hormones of reproduction in domestic animals

A class lecture useful for veterinary students, practitioners, and researchers.

1. HORMONES OF
REPRODUCTION IN
DOMESTIC ANIMALS
Prof G N Purohit

5. Pineal gland Melatonin
Liver Insulinlikegrowthfactors
(IGFI&IGFII)

6. Gonadotropinreleasing hormone
(GnRH)
Dopamine
Corticotropicreleasing hormone
(CRH)
Growth hormone -releasing hormone
Oxytocin

7.  Anterior Pituitary
Follicle stimulating hormone
Luteinizing hormone
Prolactin
Adrenalocorticotropichormone
Posterior pituitary Oxytocin
Hormones secreted by pituitary gland

8. GraafianFollicle
Estrogen Inhibin
Corpus Luteum
Progestins Relaxin

9. Leydigcells
Sertolicells
Androgens
Inhibin

10. Human chorionic gonadotropinhCG
Equine chorionic gonadotropineCG
Estrogens/ Progestins
Relaxin
Placental Lactogens

12. Uterine Endometrium,
Seminal Vesicles,
GraafianFollicles
Prostaglandin F2α
(PGF2α)
Histology of Bovine
Uterus

13. Identified by Nobel Laureates Roger Guillemin and Andrew
V Schally in 1977. GnRH is released from nerve endings at
the median eminence of the hypothalamus, where it is
stored in secretorygranules; it then travels through portal
vessels to reach the adenohypophysiswhere it binds to
receptors on gonadotropesin the pars distalisof the
hypothalamus
Neuropeptide---Arcuatenucleas—Tonic release
---Preopticarea—Surge like release
Transported and stored in median eminence and released into
hypothalamo-hypophysealportal system on stimulation
Reaches Anterior pituitary and causes the release of FSH and LH
Has a short half life of 2-4 minutes
Target tissue is Gonadotrophcells (Anterior pituitary)

14. Neurotransmitters Photoperiod/Environment
GnRH Neurons Kisspeptin
Mediobasalhypothalamus (GnRH pulse generator)
GnRH Norepinephrineincrease GnRH
Opiods, dopamine and GABA
decrease GnRH
Estrogens also regulate secretion

17. GnRH secretion IN MALES
In males the surge centre
becomes inactivated during
fetal life.
In males there are between
4-12 GnRH peaks per day.

18. Buserelin most potent analog
Fertirelin
Gonadorelin
Analogs ------Leuprolideand deslorelin
Analogs/agonists cause an initial stimulation of pituitary
gonadotropsthat results in secretion of FSH and LH
however, on prolonged use they cause a down regulation
and inhibition of pituitary-gonadal axis.
Suppression of estrus with prolonged use have rendered
them useful for estrus suppression in bitches.

19. Anestrus
Ovulation
induction
Ovarian Cysts
Estrus
Synchronization
Postpone estrus
in bitches

20. (Buserelinacetate)
(Deslorelin)
(Leuprolide)
(Gonadorelin)

21. GnRHanalogTradeName Company Dose and indications
Cattle/BuffaloSheep and
Goat
Mares Bitches Camels
Buserelin
acetate
Receptal
Pregulate
MSD
Virbac
Anestrus20µg
IM
Ovariancysts
20-40µgIM
Delayed
ovulation5-10
µgIM
Ovariancysts
10µgIM
Ovulationof
maturefollicle
Cysticchanges
inovaries40
µg
Anestrus20µg
twiceat24h
interval
Ovariancysts
40µgIM
Fertirelin Conceral Takeda
Chemicals
Japan
50-200µgIM
GonadorelinFactrel50
µg/mL
Fertagyl
Cystorelin
Zoetis
MSD
ForteDodge
100µgIM
estrus
synchronizatio
nandovarian
cysts
Deslorelin Sucromate
Ovuplant
Suprelorin
Thorn
Zoetis
Virbac
1.5mg
2.1mg
4.7mg
9.4mg
Ovulation
induction1.5
mg48hbefore
planned
ovulationwhen
thefollicleis
30-40mm
Preventionof
breeding,
estrus
inductionin
femalesand
chemical
sterilizationof
maledogs
Leuprolide Lupride
LupronDepot
SunPharma
India
Abbvie
EndocrineInc
3.75mg 0.10mg/KgSC
onceforestrus
induction

22. DETIRELIX
CETRORELIX
GANORELIX
AZALINE
ACYLINE
GnRH ANTAGONISTS
(under development)
Use
Pregnancy termination
Estrus suppression in Pets

23. Octapeptide(neuropeptide)
Synthesizedbyneuronsofsupraoptic
nucleus(smallamountbyCL)
Actsonlyonauteruspre-sensitized
withestrogen
Transportedaxonallytostoragesitesin
posteriorpituitary
Itupregulatestheactivityofsmoothmusclecells
intheuterusandthesmoothmuscles
surroundingthealveoliductsofthemammary
glands.

24. Milk let down
Transportofbothsperms&oocytes
inthetubulargenitalia
Atparturitioncauses myometrial
contractions
Lutealregressionincow&ewe

25. Induction of foaling in mare after 340
days of gestation
Treatmentofuterine
inertiainbitches
Foruterineinvolution
Expulsionofaretainedplacenta
(ROP)inmareandbitch
(ROP in Mare)
Foaling in mare

26. Suggested doses of oxytocinin
Obstetrics cases (I/M)
Cattle & Mare 60 -100 IU
Sow, ewe & doe 30 -50 IU
Bitches 10 -20 IU
5 IU / ml oxytocin

27. Secreted by lactotropsor mammotrops
cells of anterior pituitary gland
Lactotrophichormone Suckling is a
potent stimulus for prolactin secretion
Luteotropicin rodents & bitch
Maternal behavior
Prolactininhibitory hormone Dopamine
Half life 20 minutes

28. Prolactin suppress LH surge & ovulation thus
antiprolactins can presumably stimulate LH and
ovulation
Antiprolactins (dopamine agonists)
(Bromocryptine, cabergoline, metergoline)
Timely ovulation in cows, in bitches for estrus
induction, pregnancy termination, pseudopregnancy .
Bromocryptine 30-100 µg/Kg for 6-10 days
Cabergoline 5 µg/kg for 5-7 days
Domperidone (dopamine antagonist) & sulpiridefor
estrus & ovulation induction in mares (1 mg/kg) and
probably for increase in milk production in cows
(metoclopramide and domperidone)

29. Follicle stimulating hormone (FSH)
Luteinizing hormone (LH)
Human chorionic gonadotropin(hCG)
Equine chorionic gonadotropin(eCG)
Thyroid stimulating hormone (TSH)
Inhibinand Activins

30. Also known as Lutropinor Interstitial
Cell Stimulating Hormone in males
Produced by basophillicgonadotroph
cells of anterior pituitary gland
LH surge around 6 h in cattle
Heterodimericglycoprotein
Half life –20 minutes

31. Inmales
LH
Leydigcells Testosterone
(Testes)
Infemales
LH
Thecainternacells Oestrogens
LH
Lutealcells Progesterone

33. Delayed Ovulation
Planned Ovulations
Ovarian Cysts
Corpus Luteumdevelopment

34. Produced viagonadotroph cells(Ant.
pituitary)
Targettissues
Sertolicells (Testes) Granulosa cells
(ovary)
Inhibin, Estradiolsynthesis&
Androgenbindingprotein folliculardevelopment
Halflife3–4hours

35. Multipleovulationsinembryotransfer
Anestrus
Outofseasonbreeding
Estrus synchronization especially
duringnonbreedingseason

36. Secreted by fetal trophoblasticcells of
endometrial cups of equines between day
35 and 150 of pregnancy
Immunoprotection of fetus
Formation of accessory corpus luteum
FSH & eCGshare a common receptor

37. Anestrus
Superovulation
Out of season breeding

39. Produced by syncytialtrophoblastcells
of human placenta
LH like activity with little or no FSH
like effects
Half life 24 hours

40. Induction of ovulation
Treatment of ovarian cysts
Delayed ovulation

42. hCG Name Compan
y
Pack Use,modeofadministrationanddose
Cows/buffalo Mares Sheepand
goat
Sow Bitches
ChorulonMSD 1500IUOvariancysts
3000-5000IUIM
orIV
Delayed
ovulation/
Anovulation
1500-3000IU
Inducing
ovulation
2000-2500
IUwhenthe
follicleis
above35
mm
250-500IU
for
ovulation
induction
Inducing
ovulation
500-1000
IUIM
500IUfor
inducing
ovulationin
estrus
inducedby
eCG(250
IUIMfor9
days)
eCG +
hCG
PG600 Merck 400IU
eCG+
200IU
hCG
- - - Estrus
induction
-
eCG
FolligonMSD 1000IUAnestrus/Outof
the season
breeding800-
1000IUIMorSC
Superovulation
2000-3000IU
-do not
respond
Out of
season
breeding
100-500IU
IM after
progesteron
e
Estrus
induction
1000-1500
IU5-7days
after
weaning
Inducing
estrus250
IUIMdaily
for10days

44. Inhibin×FSH
GnRH Inhibin
Insulin like growth factor I Inhibin

45. Produced within granulosacells in
females & sertolicells in males
Stimulates
FSH synthesis
Cell proliferation
Cell differentiation
Apoptosis
Homeostasis
Keratinocytes
FSHinducedaromatization

46. Progestagens
Androgens
Estrogens
Corticosteroids

47. Lipophiliccompounds
Primary steroid producing tissues
Testes, ovaries, adrenals, placenta
fetal gonads
Steroids bound to large carrier proteins
Classical steroid sex hormones
Oestradiol–17 β, testosterone,
progesterone
Albumin Globulin

49. Estrogen is primary female sex hormone
Development offemale reproductive
system&secondarysexcharacteristics
Naturalestrogens:17βestradiol,estrone,
estriol,conjugated equine estrogens:
equilin,equilenin,estronesulphate
Syntheticestrogens:
Estradiolvalerate,estradiolcypionate,
estradiolacetate,estradiolbenzoate,
ethinylestradiol,Diethylstilbesterol
Phytoestrogens&mycoestrogens

50. Anabolic
Mammary development
Skin growth
Follicular growth
Estrus expression
Receptivity to male
Luteolyticin ruminants
Luteotropicin sow & mare
At parturition contraction of uterus

51. Anestrus
Fetal mummification
Fetal maceration
Pyometra
Metritis
Estrus synchronozation
In bitches
misalliance, estrus suppression,
spayed bitches
Side effects

53. •Tamoxifen
•Clomiphene
citrate 300 mg

55. Synthesized by
corpus luteum, feto-placental unit,
adrenal cortex. Secretion is controlled by
LH, PG, prolactin and many other
intermediaries
Role
Ovulation, implantation, pregnancy
maintenance, lactation, initiation of
follicular growth waves, development of
dominant follicle.
Half life 22-36 min in cow
CL dependent species cow, doe, bitch,
sow, buffalo, camel
CL independent species mare, ewe

56. Medroxyprogesterone acetate (MPA)
Megestrolacetate
Melengestrolacetate MGA
Proligestone
Flurogestoneacetate FGA
Norgestomet
Progesterone vaginal implants
Altrenogest (Nor-testosterone derivative
with progesterone like activity)
Hydroxyprogesterone caproate

57. Estrus suppression
Estrus synchronization
Pregnancy maintenance
Induction of new follicular wave
Anestrus
Ovarian cysts
Lutealinsufficiency
Vaginal prolapse
Prevention of abortion

58. Estrus suppression in the dog at the dose rate of
2 mg/kg every 3-4 months
MPA(60 mg impregnated vaginal sponges) has
been used for estrus synchronization in goats
and sheep.
Similarly it has been used (300 mg intravaginal
sponge) in cows for estrus synchronization.
Megestrol acetate
Oral progestin for estrus suppression in dogs (0.5-
2.0 mg/kg /day for 8 days)
Estrus synchronization (40-50mg/day for 14-20
days) in beef cows

59. Proligestone
estrus suppression in the bitch by IM administration
(50mg/kg SC every 3 weeks)
Flurogestone acetate
intravaginal sponge preparation (containing 20 mg FGA)
to synchronize estrus in sheep and goats.
Norgestomet (Synchromate-B)
ear implant for estrus synchronization in cattle
Progesterone vaginal implants
CIDR/PRID for estrus synchronization in cattle
Altrenogest (allyltrenbolone) Regumate
Estrus control in mares (0.044mg/Kg) and pigs
(15mg/day) for 7-10 days administered orally.
Hydroxyprogesterone caproate
Depot injection

60. CIDR with
applicator
PRID

61. Aglepristone
The twice daily SC
administration of
10mg/kg
Onapristone
•Mifepristone
•Pregnancy termination in the bitch 2.5
mg/kg BD for 4.5 days beginning at Day
32 of pregnancy

63. Anabolic Growthofmusclemass
&territorialmarking
Bonedensity Libido&
&Strength Spermatogenesis
SecondarySexCharacteristics Growth
&deepeningofvoice ofhump
Androgens

66. Testosterone
Hydroxytestosterone
Testosterone propionate
Dihydrotestosterone
Trenboloneacetate
Nandrolone(potent anabolic)
Methyltestosterone
Mibolerone(estrus suppression in
the bitch 30-60 Ugdaily orally)
Norgestrel

67. Growth promoters
Estrus suppression
Cryptorchidbulls
Delayed puberty in bulls
Androgenizedcows as teaser
Side effects

69. 
Leuprolide, abarelix,
goserelin, triptorelin
Flutamide, finasteride,
cyproteroneacetate
Ketoconazole
,Spironolactone,
medroxyprrogesterone acetate
Benign prostatic hyperplasia –
finasteride0.1-0.5 mg/kg for dogs
Lower
production of
androgens
Receptor
blocker
Others

70. Prostaglandin (PGF2α)

71. Foundinalmosteverytissue
Has20carbonatoms&5carbonring
Producedwithinuterineendometrium &
vesiculargland
Precursorisarachidonicacid
Targettissueinfemales
corpus luteum,uterinemyometrium,
ovulatoryfollicles
Prostaglandin(PG)has2derivatives
Prostacyclines&thromboxanes

72. Natural PG analogs
Synthetic PG analogs
Dinoprost, tiaprost, carboprost
Cloprostenol, fluprostenol,
prostalene, fenprostalene

74. Metritis
Pyometra
Mucometra
Endometritis
Retention of placenta
Fetal mummification
Fetal maceration
Hydrometra
Estrus induction
Estrus synchronization
Induction of parturition
Vetromedicaltermination of pregnancy

76. Polypeptide placental hormone
Also called as chorionic somatotropin
Similar to growth hormone
Stimulate the growth of alveoli during
pregnancy (mammotropic )
Luteotropic

77. Produced by: corpus luteum, placenta,
ovaries throughout pregnancy
Target organs: cervix, vagina, pubic
symphysisand related structures
Used for pregnancy diagnosis in bitch &
cat

78. The above lectures are also explained in
video lectures at my YouTube Channel Govind
Narayan Purohit
Kindly share the videos and subscribe to my
channel if you like them
Thanks