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BVETMED2 > Urogenital > Flashcards

Urogenital Flashcards

1
Q

What are the attachements of the Uterus

A

Broad ligament - Bilateral sheets of peritoneum that anchor the organ to the abdominal and pelvic walls.

Mesentry:

  • Mesometrium - Uterus
  • Mesosalphinx - Oviduct
  • Mesovarium - Ovary

Inter-cornual ligament - between uterine horns

Proper ligament - Caudal pole of ovary to adjacent horn

Suspensory ligament - Cranial pole of ovary to abdominal wall, adjacent to last rib

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2
Q

What are the blood vessels of the female reproductive tract, also where the lymp drain

A
  • Uterine artery** - from internal iliac (external in mare)
  • Ovarian artery - from aorta
  • Vaginal artery
  • Ovarian artery and vein in close contact to allow local concentration of PGF2a to remain high instead of entering systemic ciruclation

Lymph drains into aortic and sacrial-iliac LN’s, can be palpated for enlargement in infections

**rupture can cause acute death, can occur during pregnancy

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3
Q

How is the CL formed and how doe it regress

A
  • When follicle ruptures corpus haemorrhagicum forms, fills with blood.
  • Theca interna differentiate to small luteal cells and granulosa cells become large luteal cells
  • CL formed and secretes progesterone (can be palpated rectuly in cows)
  • Luteolytic factors cause breakdown by macrophages, with fibroblasts laying down type I collagen
  • Leaves a corpus albicans
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4
Q

Describe the structure of the oviduct

A
  • Infundibulum - Has projections called fimbrae, capture oocyte
  • Ampulla - muscosal folds with ciliated epithelium, Fertilisation site
  • Isthmus - Meets uterus at uterotubular junction. thick mucosal walls
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5
Q

What is the function of the cervix

A
  • Transport sperm
  • Barrier to sperm
  • Reservoi of sperm
  • Block bacterial invasion during pregnancy
  • Birth canal
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6
Q

Describe structure of vagina

A
  • Closer to cervix, columnar epithelium (secretory). Tubular glands in the submucosa that secrete into mucosa
  • Near vestibule, stratified squamous epithelium, thickens in response to eosterogen
  • Fornix can be mistaken for cervix during AI
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7
Q

What are the effects of progesterone

A
  • Converts endometrium from proliferative stage to secretory stage, preparing uterus for implantation
  • Thickens vaginal epithelium, making it impentrable to sperm
  • Decrease maternal immune sytem allow implantation and maintenance of pregnancy
  • stimulate development of mammary glands but supress milk production
  • Hyper-polarises membrane, preventing smooth muscle contraction
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8
Q

How does the dominant follicle survive a fall in FSH

A
  • Under the influence of Oestrogen, granulosa cells aquire LH receptors
  • Early-mid follicular phase, Oestrogen excerts negative feedback on hypothalamus decreasing FSH
  • Dominant follicle can survive drop in FSH because it can respond to LH
  • oestrogen rises above threshold, causing positive feedback on hypothalamus, causing an LH surge and ovulation
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9
Q

Describe the 4 stages of follicular development

A
  • Pre antrum - Independant of FSH ( primary & secondary follicle)
  • Antrum - Gonadatropin dependant
  1. Recruitment - Small antral follicles recruites to grow.
  2. Selection - Follicles are either selected to grow furthur or become atretic. dependant on concentration of FSH at the time, if high aromatase is expressed, allowing expression of LH-R. inhibin conc is moderate
  3. Dominance - Single dominant follicle now remains (Monotoccus). FSH decreases furthur, due to inhibin & E2 rises along with LH. Follicle now soley dependant on LH, high blood supply.
  4. Atresia - No FSH & small blood supply causes remaining follicles to become atretic
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10
Q

What factors Cause rupture of the graffian follicle

A
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11
Q

What is the physiological mechanism of synchronization in sheep

A

Ram effect

Stimulate ovulation in anoestrus ewes by chemosensory cues. Ewes must have been previously isolated from rams for 3-4 weeks. Not effecting in ewes in Deep anoestrus, must be just before breeding season. Ovulation will occur within 6 days. Priming with Progesterone increases %

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12
Q

What are the 3 Pharmacological methods of synchronization in sheep

A

Prostagens

Work in cyclic ewes. Supresses gonadotropins, on withdrawel increase in oestrogen. Treatment must last the length of the luteal phase (12-14 days). In anoestrus ewe withdrawel will be complimented with ECG (PMSG).

Prostaglandins

PGF2a, causes luteolysis. Animals must be in luteal phase. Oestrus within 2-3 days. Corpus luteum is refractory up to day 5, therefore 2 injections must be given 10-14 days apart.

Melatonin

Advance the onset. Must be inititiated after periods of long day length. need to elevate melatonin for 5 weeks.

Other factors:

  • Genetics - Breed differ in ovulation rate
  • Nutrition - Rising plane of nutrition can cause ovulation (flushing)
  • Immunization - To steroids and inhibin, increase gonadropin secretions
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13
Q

What are the two ways you manipulate eostrus in cows

A

PGF2a

From day 6-17 will cause luteal regression. 2 Injections required because animals are all at different stages of cycle. 2nd injection 11-13 days after first. Variable time of onset due to different sizes of follicles, E.g large follicle = short onset.

Prostagens

Mimic luteal phase. treatment for 10-12 days. combine with luteolytic factor at the end of treatment or E2 at start. Osterogen at the start preffered as it effects follicular dynamics.

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14
Q

Whats unique to the mares oestrus cycle and how can the cycle be manipulated

A

LH surge lasts for days in the mare, & ovulation can occure before the end of the surge.

Photoperiodic stimulation - Exposure to 16h day light in Nov can advance ovulation from april to early feb. Combined with GnRH infusion, infused to mimic pulsultile release.

When doing embryo transfer mares must be in same stage of cycle. PGF2a anologue use to induce luteolysis. hCG then given to induce ovulation 24-48 hours

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15
Q

How is oestrus manipulated in sows

A

Prostagens

Oral treatment for 18 days in gilts and 5-17 days in sows. Oestrus within 5-6 days of withdrawel. Difficult to dose in group fed animals and contraindicated in pregnant sows.

Gonadropins

hCG & PMSG

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16
Q

Whats unique about oestrus in the bitch and how is it maniupulated

A

Luteal phase is longer than gestation, therefore no maternal recognition of pregnancy

synthetic prostagens

Medroxyl progesterone acetate (MAP). Drug is antioestrogenic controlling vulval swelling and bleeding. also anti gonadropic. BUT can induces release of GH. Causing agromegally, mammary tumours and diabetes mellitus.

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17
Q

How is oestrus controlled in the queen

A

Luteal phase is induce by mating. pseudo-pregnancy if infertile after mating.

  • hCG - Induced ovulation & delay subsequent calling because she goes through fake pregnancy
  • Androgens - Anabolic steroids used daily 30 days before oestrus
  • Progesterone - Can be given to prevent pregnancy. given as soon as calling begins. prevents pregnancy. Can be given during anoestrus also to perminantely postpone cycle.
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18
Q

What is the definition of puberty

A

period when endocrine and gametogenic functions of gonads have first developed to a point where reproduction is possible

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19
Q

What are the factors affecting timingof puberty

A
  1. Photoperiod - E.g Lambs born in spring ovulate in 26-35 weeks whereas lambs born in autumn ovulate in 48-50 weeks
  2. Genotype - Dairy cows undergo puberty quicker than beef
  3. Social cues - E.g exposure to boars can decrease at puberty
  4. Nutrition - First oestrus generally occurs at 300kg in heifers. so increased nutrition will reach this weight quicker
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20
Q

What are the two proposed mechanisms for puberty

A

Gonadostat hypothesis

  • Pre-puberty hypothalamus is VERY sensitive to steroidal feebdack => decreases GnRH
  • Post-puberty hypothalamus is less sensitive => increased GnRH

Hypothalamic maturation hypothesis

  • Increased activity of GnRH neurones due to changes in neuronal input ( from social cues, nutrition).
  • Juvenile monkeys given GnRH begin cycling and when its removed stop cycling (proof)

Monkeys where gonadectomized at birth. LH & FSH levels range in adult range for 10 weeks but no negative feedback causes levels to fall. At 2.5 year (normal puberty age) LH/FSH levels rise again to adult range = puberty. NO sensitisation has occured yet puberty occured, therefore gonadostat hypothesis incorrect.

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21
Q

What is leptin and what is its importance

A

Leptin is secreted from adipocytes to influence metabolism and fertility. Degree of adipocity reflected in leptin secretions. No leptin receptors on GnRH neurones therefore kisspeptin acts on pituitary directly. GPR54 is receptor for kisspeptin.

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22
Q

Describe blood supply to male urogentals

A
  • Testicular artery - branches from aorta just below renal artery
  • Right testicular vein - Caudal vena cava
  • Left testicular vein - Left renal vein

Arranged in a countercurrent system for temperature regulation, known as pampiniform plexus

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23
Q

What is a problem with intra cytoplasmic sperm injection

A

Magnification isnt high enough to see morphology abnormaltities. therefore could be introducing genetically poor sperm

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24
Q

What is automated sperm morphology analysis (ASMA)

A

Classifys sperm as normal and abnormal for selection for IVF. Although these sperm could have variation in fertility E.g acrosomal integerity

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25
Q

Why do sertoli and leydig cells secrete oestradiol?

A

Regulates absorption of fluid into epididymis, allowing sperm maturation

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26
Q

How does sperm maturate in the epididymis

A
  • Stabilise nucleus - Condensation of nuclear chromatin
  • Stabilise plasma membrane - Addition of surfave glycoproteins (decapacitation factors)
  • cAMP levels increased in tail => motility
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27
Q

Describe fluorescent staining and flow cytometry

A
  • SYBR-14 stains intact plasma membranse green
  • Propidium iodide stains sperm with damaged membranes red
  • Sperm pass a laser which excites fluorescent particles
  • These can either be counted or a assigned an electric charge dependant on fluorescent at certain wavelengths
  • IF electrical charge is assigned sperm can be assorted
  • Allows for sorted semen which are viable and sexed
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28
Q

What is comet assay ?

A
  • Cell is placed in argarose gel and lysed
  • Electrophoresis
  • Intact DNA fragments to large to move
  • Poor DNA integrity will cause large fragmentation
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29
Q

Describe the event that occur at capacitation

A

Progressive destabilisation of the plasma membrane

  • Glycoproteins coating sperm head removed, exposing ZP3
  • Membrane fluidity increased to aid breakdown of acrosome
  • Mobilisation of intracellular Ca+2 in acrosomal reason
30
Q

Describe the events that occur at hyperactivation

A
  • Increased intracellular Ca+2 => increased cAMP
  • occurs in oviduct at uretotubal junction, isthmus
  • Increased head movement, velocity curvilinear (VCL) & decrease linearity (LIV)
31
Q

What is CASA

A

Computer assisted semen analysis

Use motility measurments to determine the fertility of semen

32
Q

Describe the acrosome reaction

A
  • Fusion of sperm plasma membrane and outer acrosomal membrane
  • Fusion causes vesiculation and release of hyaluronidase and acrosin which digests a whole in zona pellucida & sperm moves into pervitelline space
  • Equatorial segment exposed for oocyte fusion. equatorial segment binds to oocyte plasma membrane.
  • Cortical granules released to prevent pollyspermy
33
Q

What is CTC staining

A
  • Chlortetracylcine staining
  • Binds to intracellular Ca+2
  • When sperm is capacitated fluoroscene free band can be seen in post acrosomal region
  • When sperm has undergone acrosome reaction theres dull or absent fluorescence in head
34
Q

Why do we use AI

A
  • Prevents transportation of animals which is stressful
  • Global genetic selection possible
  • Selective breeding
  • Preservation of endangered species
  • Biosecurity (foot and mouth)
35
Q

What are the two ways in which semen are stored

A
  1. Room temperature - Decreases the metabolic rate. diluted in ‘extender’ solution, similiar composition to seminal plasma. lasts for 3-5 days. Does not allow for period of quarentine or long term storage. commonly used with pigs
  2. Semen freezing - Stored in liquid nitrogen at -196 degrees. Fertile for 10+ years. Can breed from animal after death. is unsuccesful in pigs.
36
Q

Describe event that occur after fertilisation

A
  • Male and female pronuclei fuse
  • Cleavage occurs, series of mitotic divisions up to 8 cell stage (blastomers)
  • After 8 cell stage now morula stage
  • 2 distinc layers form, ICM & trophoblast
  • Outer cell mass pumps sodium (obligatory water) into blastocyst, forming blastoceole
  • ICM forms embryo & trophoblast form placenta
  • In uterus, blastocyt has to digest zona pellucida to allow implantation
37
Q

Explain the arrangement of the uterine vein & artery

A

The lungs are filled with prostaglandin hydrogenase which will break down any prostaglandins in systemic circulation. therefore when released, PGF2a can diffuse between blood vessels keeping local concentration high

38
Q

What is the MRP in cats and how do we know they need one ?

A
  • Luteal phase only occurs after mating
  • During pseudo-pregnancy, CL lasts 40-45 days. But duration of gestation is 60 days. therefore MRP is required
  • Prolactin!
39
Q

What is the MRP in domestic ungulates and how was this proved with a test

A

Interferon tau

Uterine horns were surgically seperated. One side was maintaint pregnancy and the other wasnt. In the pregnant horn, interferon tau levels were high and oxytocin receptors were low. in the non pregnanct side interferon tau levels were low and oxytocin receptors werre high.

40
Q

What is MRP in the sow and what are its effects

A
  • MRP is oestradiol, foetus required in each horn or PGF2a will be produced and terminate pregnancy
  • Oestradiol redirects PGF2a synthesis towards endometrial lumen (exocrine) instead of diffusing into blood (endocrine). Fails to reach ovary
  • PGF2a in lumen is either metabolised or causes contraction, allowing even distribution of foetuses in available space
  • Oestradiol also promotes production of PGE2 which promotes P4 secretions from CL
41
Q

Explain why eCG cant be MRP in mare

A
  • Normal mare cycle is 21 days
  • day 36-38 trophoblast migrates into endometrium , forming endometrial cups. These secrete eCG
  • Therefore cant be MRP because it would have been secreted before 21 days

eCG along with FSH stimulates secondary ovulation. Forms accessory CL, supplements P4 until day 100 where placenta takes over

42
Q

Describe a timeline of the horses cycle up to day 35 after ovulation

A
  • day 3 - Embryo secretes PGE2, for oviduct transport
  • day 5 - Embryo enters uterus
  • day 10 - Conceptus secretes oestrogens. These cause secretions of PGF2a and PGE2, aid in uterine transport
  • day 15 - Increase in uterine tone, fixation of foetus
  • day 35 - Endometrial cup formation
43
Q

Describe the process of placental development

A
  1. Primitive endoderm moves down covering the trophoblast cells, forming the yolk sac
  2. Downwards moving mesoderm along with trophoectoderm form the chorion
  3. The yolk sac can make contact with the trophoectoderm, facilitating exchage. Choriovitelline placenta. (non mammals/marsuples)]
  4. Allantois is then formed (out pouch from the embryo). Contains blood vessels and its function is to exchange nutrients/waste
  5. Allantois fuses with chorion forming allantochorion

This is a chorioallantoic placenta. formed by ruminants, pigs & humans.

Horses and carnivores have a choriovitelline placenta and then a chorioallantoic placenta

44
Q

Name the 5 classifications of placenta

A

1) Fetal membranes present:

  • Choriovitelline - Non mammals
  • Choriovitelline to chorioallantois - Carnivores & horse
  • Chorioallantois - Ruminants, pigs & humans

2) Grass shape:

  • Discoid - humans, rodent
  • Cotyledonary - ruminants
  • Zonary (ring) - Carnivores
  • Diffuse - pigs, equids

3) Implantation:

  • Centra - superficial -ungulates
  • Eccentric - semi implanted - carnivores

4) Cell layers, maternal to foetal membrane

  • 6 layers - epithelialchorial - ungulates
  • 4 layers - endothelialchorial - carnivores
  • 2/3 layers - haemochorial - human/rodents. Trophoblast cells invade maternal blood vessels

5) Interdigitation at attachment points

  • Folded - Pigs
  • Lamellar - carnivore
  • Villous - equids, ruminants and humans
45
Q

What classification of placenta does a pig have

A
  • Chorioallantoic
  • diffuse
  • central
  • epitheliocortical
  • folded

A vascular necrotic tips

46
Q

What classification of placenta does a horse have

A
  • Choriovitteline to chorioallantoic
  • Epitheliochorial
  • central
  • Diffuse
  • Villous

Contain microscopic microcotyeldon. Can only cope with one foetus as it requires nutrients from the whole uterus. Will abort at 9 months.

47
Q

What is the classification of placenta of ruminants

A
  • Chorioallantoic
  • Cotyledonary
  • Central
  • epitheliochorial
  • Villous
48
Q

What is the classification of placenta for carnivores

A
  • Choriovitelline to chorioallantoic
  • Zonary
  • Eccentric
  • endothelialchorial

a band of tissue around around conceptus

49
Q

Explain the exchange of nutrients in the placents

A
  • Na+, K+, Cl-, fatty acids, steroid, gas and urea move by simple diffusion
  • Less soluble molecules needed in large amounts for facilitated diffusion. e.g glucose. Glucose transporters asymmetrically distruted on trophoectoderm to stop excretion out of placenta.
  • Oxygen diffuses freely across placenta, rapidly reaching equilibrium. Equilibrium exploited by :
  1. Fetal haemoglobin has higher affinity
  2. Fetal blood contains more haemoglobin
  3. Fetus to mother loss of C02 enhances 02 transfer
  4. Mother to fetus 02 loss causes increased affinity for C02
  • Potentially toxic (I-), igG, Na+,K+,Cl- exchanged by active transport
50
Q

How is iron uptaken in the mare and carnivore foetus

A
  • Mare - Progesterone dependant secretions of uteroferrin
  • Carnivores - Seppage of RBC’s from mother taken up by trophoblast
51
Q

How does the placenta protect the foetus from trauma & teratogens

A
  • Physical - Amnion associated with fluid cushion
  • Teratogens are external influences that induce developmental abnormalities. Either non iatrogenic (Microrganisms, radiation) & iatrogenic (tetracyclines)
52
Q

What are the immunological functions of the placenta

A
  1. Fetal evasion - Reduced expression of MHC class I at fetal/maternal interface. No MHC class II
  2. Defence mechanism - Derive products that modulate local environment. E.g IDO, which depletes tryptophan and inhibits Tcell proliferation
  3. Shift - Progesterone induced uterine proteins suppress prolifertion of lymphocytes in ruminant uterus
53
Q

What hormones are secreted by the placenta

A
  • Progesterone (DHP secreted by mare at 210 days when P4 dips
  • eCG - highly glycosylated LH, long half life. Luetrophin, causes of 2nd ovulation/CL
  • Oestrogens - Growth of myometrium, Proliferation of endometrium and stimulates uterine blood flow
  • Placental lactogens - Produced by placenta in ruminants, humans and rodents. Alters carbs/protein metabolism, mammary development and Luteotrophic
  • oPL - Production of IGF-1 in mother. causing insulin resistance. Causes glucose intolerance increasing glucose absorption in fetus. increase lipolysis, proteolysis & ketogenesis.
  • Relaxin - Release just prior to parturition. Causes relaxation of the uterine ligaments, cervical softening, expansion of birth canal & mammary gland devlopment.
54
Q

Describe internal anatomy of mammary gland

A
  • Streak canal - Keep milk in udder and bacteria out
  • Teat cistern - Duct in teat, 30-40mml of milk. Seperated from streak canal via rosette
  • Gland cistern - seperated from teat cistern by cricoid folds. holds 400mml of milk
  • Stroma - Contains fibroblasts, adipocytes, plasma cells & blood vessels
  • Alveoli - Secreting epithelium. each surrounded by myopithelium & capillaries. Groups of alveoli empty into ducts, forming functional unit lobule=> lobe.
55
Q

What are the 2 ligaments of the mammary gland

A

Median Suspensory ligament - Seperates left and right udders. Elastic tissue allows distention for weight of milk

Lateral suspensory ligament - Inflexible and surrounds outer udder. Attached to prepubic and sub pubic tendons

56
Q

Describe the circulation of the mammary gland

A

One gallon of milk requires 400 gallons of blood!

  • External pudic artery has 2 branches. 1 for each udder. Arranged in a sigmoid flexure to avoid damage due to excessive weight
  • Mammary artery branches into cranial and caudal mammary artery

Blood exits via:

  1. Subcutaneous abdominal vein - When standing. empties into cranial vena cava
  2. External pudic vein - when sitting. Empties into caudual vena cava
57
Q

Describe mammogenesis

A
  • Mammary ridge proliferates into mesenchyme (dermis)
  • Branches out, furthur penetrating dermis
  • Each branch lengthens forming duct systems. Myoepitelial cells surround teminal portions
  • Parathyroid hormone like protein induces BMP4 receptors. Binding causes MSX2 expression. causing no hair growth.
58
Q

Describe lactogenesis and galactopoiesis

A

Lactogenesis

  • Ability to secrete milk
  • Lactating in late gestation = stage 1
  • Lactation after birth = stage 2

Galactopoiesis

  • The production of milk dependant on removal of milk.
  • When its not removed, capillary supply decreases. Supply demand response
59
Q

Describe the hormonal influences on mammary gland

A
  • Osterogen - Inhibits milk secretion. develops stromal tissue & growth of extensive ductal system.
  • Progesterone - Promotes lobule/alveoli development. Inhibits milk secretion
  • Prolactin - Promotes milk synthesis. Dopamine usually inhibits prolactin. Increase in prolactin causes increase in oxytocin. suckling inhibits dopamine.
  • Decreases in progesterone and oestrogen causes increased prolactin
  • GH works synergistically with oestrogen to develop ducts.
  • Glucocorticoids - maintain tight junctions in breast parenchyma
60
Q

Describe milk ejection reflex

A

Suckling causes neuronal messages to paraventricular & supraoptic nuclei of hypothalamus => oxytocin release=> Myoepithelial contraction

61
Q

Describe involution

A

Epithelial cells de-differentiate during dry period. Non secretions within 7 days

62
Q

Describe myometrial contractions during parturition and how they’re regulated

A
  • Oestrogens stimulate hypertrophy of myometrium. Forms gap junctions allowing myometrium to act as a syncitium
  • Brachystasis - When myometrium contracts and shortens doesnt regain normal length on relaxation.
  • Uterus divided into 2 sections. Upper contractile portion and lower passive region. retraction ring can be felt between segments
  • Oxytocin - Lowers excitation threshold of muscle cells
  • Prostaglandins - Stimulates liberation of Ca+2 from intracellular stores
63
Q

Describe cervical remodelling and how its regulated

A
  • Cervical softening - Increase in GAG’s => increase keratin sulphate (binds collagen loosely) & decreased dermatin sulphate (binds collagen tightly)
  • Cervical ripening - Increased vascularisation, influx of monocytes and raised levels of IL6 & IL8
  • Cervical dilation involves - Increased hydration, disorganization and viscoelastibility

Regulated by

  1. Prostaglandins - Induce collagen breakdown, alter GAG & proteoglycan composition
  2. Nitric oxide - Inhibition of INOS prevents ripening & NO induces PG’s release
  3. Relaxin - Increases dramatically during 38-42 weeks. released from CL
64
Q

How is prostaglandin synthesis regulated

A

Oestrogen induces liberation of PLA2 from lysosomal stores, whereas P4 stabilises lysosomal membranes. When E2:P4 increases, prostaglandin production increases
Oestrogen also increases uterine oxytocin receptors

65
Q

Describe the events that occur at parturition

A
66
Q

Describe the ferguson reflex

A
  • Foetal pressure on cervix causes oxytocin release
  • Oxytocin lowers threshold in myometrium, causing contractions
  • This causes an increase in pressure on the cervix thus more oxytocin released
  • Positive feedback loop
67
Q

Which species Maintain a Corpus luteum throughout pregnancy and how is it regressed at partum

A
  • Goats
  • Cow
  • Dogs
  • Pig
  • Rabbit

Foetal stress induces ACTH release => Cortisol. Cortisol induce aromatase, which increases the conversion of DHA into oestrogen. oestrogen induces prostaglandin (PGF2a) => luteolysis

68
Q

What species have placental progesterone source and how is parturition induced

A
  • Sheep
  • Guinea pig
  • Cat
  • Horse

Foetal stress induces cortisol release. Cortisol up regulates 17a hydroxylase, C17-20 lyase & aromatase. These convert progesterone into oestrogen.

Humans lack 17a hyroxylase and C17-20 lyase enzymes, therefore cortisol doesnt initiate parturition.

69
Q

Why is the mare different in terms of hormone production during gestation

A
  • Prostagen increase at the end of gestation
  • Oestrogen decrease at parturition. Instead fetus produces large amounts of equilin and equilenin, BUT classical oestrogens required for labour initiation
  • Cortisol increases 2-3 days before parturition
  • Oxytocin decreases through pregnancy, increases at parturition
  • Fetus produces large amounts of P5, converted to P4 in placenta then DHP by 5a reductase
70
Q

How can u induce parturition in domestic species

A
  • Cow - PGF2a
  • Sow - PGF2a
  • Sheep - Corticosteroids at 144 days induce lambing in 48 hours
  • Dog & cat - Low dose oxytocin with anti progestin induces parturition
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BVETMED2 (10 decks)

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