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Flashcards in General Deck (137)
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1
Q

Andrology

A

reproduction of male animals + humans

2
Q

Gynecology

A

reproductive issues in woman

3
Q

theriogenology

A

reproductive system of animals

4
Q

obstetric

A

any intervention: females before, during and after partuition

5
Q

Determination of sex in males

A

SRY protein - sex determining region gene - located on Y chromosome

6
Q

Function of sertoli cells in fetus

A

produce anti-mullerian factor (AMF) - a hormone responsible for degenerate the mullerian ducts (primordial female reproductive tract) induce development of leydig cells

7
Q

function of leydig-cells

A

produces testosterone partly converted into DHT by sertoli cells : Dihydrotestosterone is a hormone that stimulates the development of male characteristics

8
Q

Determination of sex in females

A

No SRY or sertoli-cells so the mullerian ducts will not be degenerated since there is no testosterone produciton by the leydig-cells the wolffian ducts will degenerate ( primordial upper urogenital tract of males)

9
Q

hormones produced by the ovaries

A

inhibin and progesteron

10
Q

Layers of the female tract (outer–>inner)

A

serosa muscularis submucosa mucosa

11
Q

What is the broad ligament and what is its parts?

A

continuation of the peritoneum, fiing the uterus contains essels, nerves and lymphatic drainage Mesovarium - around the ovaries mesosalpinx - around oviduct Mesometrium - around the uterus

12
Q

What type of genital organ does the female - opossum - rabbit, mouse - pig - cow, ewe, doe - mare - human have?

A
  1. advanced duplex 2. duplex 3. bicornuate 4. bipartite 5. modified bipartite 6. simplex
13
Q

How many layers separate the mother from the fetus

A

6 (3 from mother, 3 from fetus) endothelium connective tissue epithelial endothelium connective tissue epithelium

14
Q

Placentomes of - cow - ewe - mare, sow

A
  1. convex 2. concave 3. diffuse
15
Q

placentomes are buildt up of

A

chorion, caruncle and endometrium in cow and ewe chorion, microcotyledon and endometrium in mare and sow

16
Q

what is special about the ovaries in the bitch?

A

the mesosalpinx comlpletely covers them - make it difficult for a complete spay. the ovarian bursa is making it difficult as well

17
Q

receptors in antrum

A

estrogen inhibin FSH

18
Q

receptors in theca interna

A

androgens LH

19
Q

hormones produced by corpus luteum

A

P4 oxytocin relaxin inhibin activin

20
Q

preovultory follicle - what degenerates?

A

The basement membrane - its is separating the theca interna and the granulosa cells - during ovulation and the oocyte and follicular fluid evacuates these cells start to mix - forming corpus luteum

21
Q

Corpus hemorrhagicum

A

ruptured vessels during the ovulation forms a blood clot

22
Q

cells of a functional corpus luteum

A

Large luteal cells - formerl granulosa cells small luteal cells - formerly thecal cells

23
Q

what is different about cows and ewes ovarias when it comes to palpation?

A

the ovarian medulla and cortex are reversed so we can plapate the follicle but not the corpus luteum

24
Q

structures found in 1. infundibulum 2. ampulla 3. isthmus

A
  1. fimbria 2. mucosal folds, caudally the ostium 3. uterotubal junction: regulates the movement of embryo into the uterus
25
Q

structure of the uterus

A

mucosa + submucosa/endometrium muscularis/myometrium serosa/perimetrium

26
Q

were does the uterine glands develop?

A

they develop from the endometrial mucosa and penetrates into the submucosa where they become coiled

27
Q

functions of the uterus

A

sperm transport luteolysis + control of cyclicity environment for preattachmnt embryo feeding the embryo + spermataxoa maternal contribuation to the placenta expulsion of fetus + fetal placenta

28
Q

What does the cervix provide?

A

a flushing system: mucosa production, lub + protecc a barrier: control sperm transport, isolation, protection, cervical seal during pregnancy

29
Q

who has - cervical rings - cervical folds

A
  • cow + ewe + sow - mare
30
Q

What happens to the cranial/caudl agina when there is a high level of estrogen?

A

thickening - mechanical protection - prevents microorganim immigration

31
Q

Species specific sperm deposition

A

Ru + Ca: intravaginal Su: intracervical Eq: intrauterine

32
Q

What is the main hormone of the corpus luteum after ovulation? And what was it before?

A

main hormone after ovulation: progesterone Main hormone before ovulation: estrogen

33
Q

GnRH pattern from the surge center

A

sensitive to positive feedback and will secrete in high amplitude high frequency pulses of GnRH in a short period after estradiol reaches a threshold concentration

34
Q

Why does females have surge center and not males?

A

in females the oestradiol produced by the fetus ovaries are bound to alpha-fetoprotein hormone - making it impossible to pass BBB Testosterone in males goes through BBB converts to oestradiol and “defeminize” the hypothalamus, depressing the surge center, elaving only a tonic center

35
Q

tonic center GnRH pattern

A

secretes small episodes of GNRH in a pulsatile fashion - episodi secretion is continous throughout reproductive life

36
Q

Explain the hypothalamo-pituitary portal system

A

nerve endings terminating in the primary portal plexus - a network og blood vessels that will connect the hypothalamus with the anterior lobe (medial hypophyseal artery) transporting releasing hormones and connecting the anterior lobe (secondary portal plexus) - blood and releasing hormones

37
Q

difference between the connection of the hypothalamus and the anterior/posterior lobe

A

anterior lobe: portal system only posterior lobe: no portal system, also known as neurohypophysis

38
Q

Explain the transmission of communication from the paraventricular nucleus to the neurohypophysis

A

PVN produces hormones (regulating) axons stretch down into the neurohypophysis (PL) and is released into the capillary plexus within the PL

39
Q

Result of a female having a surge center

A

preovulatory GnRH –> LH peaks

40
Q

Overview of Kisspeptin

A

neuropeptides secreted by hypothalamus neurons to stimulate GnRH secretion

41
Q

Task of kisspeptin

A

colelcts information both externally and internally - they will relay the information if the female is ready to reproduce, also the onset of the puberty

42
Q

factors kisspeptin takes into its consideration

A
  • leptin amount: too little leptin = no reproduction - blood fatty acid and glucose: needs to be positive for reproduction to start - seasonality: melatonin level
43
Q

kisspeptin and its role in seasonality

A

different meaning to different types of breeders horse: long-day - low melatonin = increase GnRH sheep: short day - high melatonin = increase GnRH

44
Q

GnRH level before and after puberty?

A

higher in female after puberty

45
Q

Which follicles are FSH dependent?

A

emerging or recruited folicles, early selected follicles

46
Q

Which follicles are LH dependent?

A

larger selected follicles, dominant follicles

47
Q

Describe the effects of estradiol and inhibin on the hypothalamus and pituitary - early follicular phase vs later in the follicular phase

A

early follicular phase - GnRH pulse increase (low P4) - secretion of FSH + LH (AL) - stimulates follicles tor produce estradiol - giving a positive feedback –> more GnRH is produced - growth of dominant follicle and ovulation later - follicles will produce inhibin - inhibin has negative effect on FSH inhibiting the growth of other follicles

48
Q

1st follicular wave

A

often 2 waves where the follicles are growing first one starts after metestrus (right after ovulation of the previous dominant follicle) no LH surge on the first wave - there is a high progesterone level with a functional corpus luteum so there wil not be any oulation this will cause the follicles to become atretic

49
Q

2nd follicular wave

A

initiated around diestrus, it initiated before luteolysis, progesterone will drop, increase estrogen and surge will be initated supporting the follicular growth only follicles that are in a growing phase when luteolysis occur will become eligible for ovulation

50
Q

Explain the “two cell-two gonadotropin” model of estrogen production of teritary follicles

A

Internal Theca cells will produce testosterone from cholesterol (LH receptors) testosterone is transported into granulosa cells (FSH receptors - FSH binds - enzymes of conversion is produced) the testosteron is converted into estradiol estradiol travels to the blood and causes estrous activity by affecting the brain and the reproductive tract

51
Q

estradiol effect on brain - behaviural

A

lordosis (mating posture) increased phonation and physical activity

52
Q

estradiol effect on reproductive tract

A

increased - blood flow - edema of tissue - secretion - leukocytes - smooth muscle activity - uterine gland growth

53
Q

Explain induced ovulation

A

requires stimulation for there to be a GnRH release - coopulation or mating behaviour like licking nerve endings in the vagina will be stimulating causing the surge center to release preovulatory GnRH surge –> LH surge –> ovulation

54
Q

animals having induced ovulation

A

Queens and rabbits

55
Q

Explain luteolysis

A

PGF2a will bind to a receptor on the luteal cells - calcium influx - apoptotic - inhibits the conversion of cholesterol into progesterone leading to a physical regression and the cycle can start again

56
Q

The effects of progesterone maintaining after ovulation

A

If progesterone is maintained (during pregnancy) it will have a negative feedback on GnRH - GnRH, LH and FSH is supressed - little secretion of estrogen positive effect on endometrium - endometrial glands increase secretion into uterine lumen - inhibits contraction of myometirum maternal recognition

57
Q

What is silent ovulation?

A

ovulation after seasonal anestrus/puberty/gestation where there is no behavioural estrus

58
Q

What is meant by progesterone priming the brain

A

after a silent ovulation, the progesterone produced by the corpus luteum will prepare it for the next estrus making it sensitive for estradiol so that there will be a full oestral behavior next time

59
Q

Protein hormone mechanism of action

A
  1. hormone receptor binding 2. activation of adenylate cyclase 3. protein kinase activation 4. synthesis of new product
60
Q

the 2 ways of mechanism of steroid hormone action

A

fast and slow response

61
Q

Fast response of steroid hormones

A
  1. steroids binding to membrane receptors 2. activation of adenylate cyclase 3. protein kinase activation 4. synthesis of new product
62
Q

slow response of steroid hormone action

A
  1. steroid transport 2. movement thorugh the cell membrane and cytoplasm 3. Binding of steroid to nuclear receptors 4. mRNA synthesis and protein synthesis
63
Q

Example of fast responses of steroid hormone

A

estradiol: ion channel alteration, increase myometrial contraction progesterone: ion channel inhibition, decrease myometrial concentrations

64
Q

example of slow responses of steroid hormone

A

estradiol: mucus secretion by female tract progesterone: uterine gland secretion

65
Q

define cycle length and mention some in different species

A

interval from estrus to the next estrus most mammals: 20-21d sheep: 16-17d primates:28-37d

66
Q

small cycle

A

estrous cycle

67
Q

large cycle

A

from fertilization (pregnancy, partuition, lactation, resumption of cyclic ovarian function) to the next fertilization

68
Q

length of anestrus, proestrus, estrus and diestrus in dogs when is the follicular phase and when is the luteal phase?

A

anestrus: 5month proestrus: 9d Estrus: 9d Diestrus: 3 month follicular phase: proestrus + estrus luteal phase: diestrus

69
Q

Dominating hormone in follicular phase

A

estradiol - secreted by the ovaries stimulated by FSH and LH

70
Q

Dominating hormone in luteal phase

A

progesterone secreted by corpus luteum + drop in progesterone after lutolyisis in strating

71
Q

hormone causing the luteolysis

A

prostaglandin F2 alpa produced by the endometrium

72
Q

The difference between estrous and menstrual cycle

A

Estrous: begins and ends with estrusand/or ovulation: long follicular phase Menses: ends with the start of menses, ovulation occurs in between two menses

73
Q

How is cyclicity connected with daylight

A

production of melatonin by the pineal gland

74
Q

how does melatonin affect short day breeders?

A

increased M will induce cyclicity

75
Q

What is meant by circuannual species?

A

Deers, small Ru, some rodents have a bilogical clock, which induces cyyclicity around the same time of year

76
Q

What is meant by non circuannual species

A

rats, mice continued photostimualtion can maintain cyclicity all year around regardless of the seasion

77
Q

Why is light programs used?

A

to induce the cyclicity earlier in the year

78
Q

Age of puberty in females - sheep, goat - swine - cattle - horse

A

7-10 4-7 8-11 15-18

79
Q

What is the breeding weight and what is it in dairy cattle?

A

% mature weight at puberty the onset of the puberty is related to development - the animal can be of proper age, but in case the body is not in the correct developmental stage, puberty/estrus will not occur diary cattle: 30-40%

80
Q

when does the endocrine reproductive system become functional?

A

end of the first trimester of fetal life

81
Q

What happens to the function of ovaries/testies after birth?

A

First they become inactivated (several months) - The GnRH pulse generator in the arcuate nucleus is inhibited

82
Q

is the reproductive system completely inactive after birth and prepuberal?

A

No, there is a subtle increase in gonadotropin pulses coming form the tonic center

83
Q

Which hormone triggers the arcuate nucleus to resume the function of reproduction?

A

Leptin. it will rise trigger the ARC which will again trigger the GnRH pulse generator - now both the tonic and surge center is active and there will be the first ovulation

84
Q

Which nucleus does the kisspeptin get information from?

A

anteroventral periventricular nucleus and arcuate nucles

85
Q

What is meant by autoamplification processes after birth

A

when getting closer to the puberty and all other factors are in place the body will start to increase the production of all the pubertal hormones of the hypothalamus, pituitary and gonads

86
Q

Primordial cell development in the ovaries

A

primordial cells migrate to the cortex of the gonadal ridge. Here the cells undergo mitotic division to increase their number prior tu puberty

87
Q

Primordial cell development in the testes

A

Primordial germ cells migrate to the medulla of the gonadal ridge and become surrounded by mesenchymal cells to form primitive sex cords

88
Q

explain - oocytogenesis - ootidogenesis - 2nd ootidogenesis

A
  • undergoes mitosis forming the primary oocytes (2n) - undergo meiosis 1 forming secondary oocytes, the primary oocytes are halted in prophase 1 of meiosis until ovulation (2n) - secondary oocytes undergo meiosis 2, reminaing in metaphase 2 until fertilised (1n)
89
Q

What is KNdy

A

the hormones kisspeptin, neurokinin B and dynorphin are released together

90
Q

role of kisspeptin related to GnRH neurons

A

they act direclty on the GnRH neurons causing the release of LH and FSH which will again have a effect on testosterone and oestradiol - important in puberty

91
Q

What modulates the activity of kisspeptin?

A

estrogen and progesterone, leptin, blood glucose, blood fatty acids

92
Q

What is leptin

A

satiety hormone, made by adipose cells - inhibits hunger

93
Q

What is ghrelin

A

hunger hormone

94
Q

What is energy flux?

A

amount of energy consumed vs expended

95
Q

Fate of follicles

A

grows to tertiary characteristic and degenerate

96
Q

what is the number of oocytes ovulated for a cow?

A

17 cycles/year x 8 years = 136 oocytes ovulated/lifetime

97
Q

How can we increase the number of ovualted follicles

A

can increase superovulation by fiving FSH to simulate the rescue of follicles which would have undergone atresia

98
Q

where should the sperm be deposited in dogs?

A

vagina

99
Q

where should the sperm be deposited in horse and cattle?

A

intrauterine

100
Q

What are some ways to detect oestrus in horses?

A
  1. observation of behavioural and clinical signs 2. winking, motion of vulva, mucus 3. contact with stallion: standing reflex (teasing) 4. rectal palpation, ultrasound 5. progesterone test
101
Q

Name the stage of cycle

A

without - di/metestrus

102
Q

Name the stage of the cycle, can we inseminate?

A

reddening - early estrus

we cannot inseminate

103
Q

Name the stage of the cycle

Can we inseminate?

A

reddeining + swelling

(check standing reflex)

estrus

YES, inseminate dat sow

104
Q

When to inseminate the sow?

A

The vulva will redden and swell for 4 days, she will start honking and mounting. here you need to wait sometimes the reddening and sweeling disspaeras and then comes back, when it comes back. do the standing test

when she is standing this usually last between 2-5 days. inseminate first on 24h and then the second time on 36 hours

105
Q

Estrus detection in cattle

  • duration
  • mounting activity
  • standing duration
A

duration of estrus varies from 2-30h

70% of mounting happens at night

average duration of a stand by a cow in heat lasts only 4-6sec

106
Q

Which hormones are responsible for the estrus behaviour?

A

it is controlled by E2 but previous P4 exposure is needed

107
Q

Estrus detection aids (cattle)

A

presence of a bull

marker animals - chin ball

pressure sensitive mount detectors and tail paint

electronic pressure sensitive mount detector

electrical resistance of vaginal fluid

pedometry

108
Q

What is a sidewinder?

A

A bull that has had a penile-prepuce transloaction

this allows normal protrusion and erection, but does not permit intromission

109
Q

What is arborization or ferning?

A

high soduium chloride presence in the mucus during estrogen effect

crystallisation

110
Q

List the major steps of oogenesis

A
  1. mitotic division of primordial germ cells (prenatal)
  2. nuclear arrest
  3. cytoplasmic growth (induced by LH surge)
  4. resumption of meiosis
111
Q

In what stage is the ovulated oocyte?

A

secondary oocyte

112
Q

How does the secondary oocyte become haploid?

A

The polar body gets extruded and is containing half of the genetic material

113
Q

What is the granulosa cells responsible for?

A

Maturation of the oocyte

114
Q

What is the journey of the spermatozoa after AI/mating? (to the oocyte)

A

it traverses the cervix, gets to the uterus. The ones that survive retrogade loss and phagocytosis/selection travels to the oviduct and enters it

here capacitation happens, hyperactive motility and phagocytosis happens before they can bind to the oocyte

115
Q

Journey of spermatozoa after meeting the oocyte

A

goes through acrosome reaction

penetrates through the zona pellusida

formation of male and female pronuclei

fusion of the male and female pronuclei

cleavage divisions start (mitotic divisions)

hatching

116
Q

Where is the capacitation initiated?

A

In the uterus, it is completed in the oviduct

117
Q

Capacitation and the specifics of the sperm

A
  • Epididymal spermatozoa: plasmamembrane covered in surface molecules (proteins and carbohydrates)
  • Coating the epididymal sperm with seminal plasma: plasma protins masking the membran molecules
  • Sperm exposed to female tract environment: seminal plasma molecules + some membrane molecules are removed
  • binding to the zone pellucida is now possible
118
Q

Zona binding: binding regions

A

ZP1 + ZP2: structural importance

ZP3: functional importance, gets in connection with the zona binding region of the sperm

119
Q

What happens during acrosome reaction?

A

the plasma membrane overlying the acrosomal membrane begins to fuse with the outer acrosomal membrane, creating pores allowing the acrosomal enzymes to leave (hyaluronidase and acrosin)

These enzymes allows the sperm to penetrate though the zona pellucida

120
Q

What happens just after the acrosomal reaction?

A

the fusion proteins are now uncovered, since the plasma membrane dissapears - they will take part in the connection of the plasma membrane of the oocyte and the head of the sperm

121
Q

Explain the sperm-oocyte fusion

A
  • after penetration of the zona pellucida, the spermatozoon reaches the perivitelline space
  • the acrosomal membrane is still intact with the fusion proteins
  • fusion proteins makes strong physical connection with the oocyte
  • fusion allows the content of the cortical granules to be released into the perivetellini space by exocytosis
  • this release i inducing the zona block, stpping other sperm cells to enter the oocyte
  • the nucleus of the sperm is now in the cytoplasm of the oocyte where it start to decondense and the sperm nuclear membrane dissapears
122
Q

List the sequence of events after capacitation

A

hyperactive motility

binding to ZP

acrosoe reaction

penetration of ZP

sperm-oocyte membrane fusion

sperm engulfed

decondensation of sperm nucleus

formation of male pronucleus

123
Q

Developmental events after fertilization and before the embryo attachment

A

Blastomeres (small cells) start to divide mitotically until the 32nd cell stage - reaching the morula stage

further divison until the blastomere stage

Hatching

124
Q

Explain the formation of blastocyst from the morula stage until hatching

A

In the outer cells of the morula there is a strong connection

in the inner cells of the morula there is loose connection

the outer cells will start to pump sodium into the inner part and this leads to an increasing osmotic pressure, water will flow into the cell creating a cavity.

  1. early blastocyst (small cavity)
  2. Blastocyst
  3. Expanded blastocyst
125
Q

Explain hatching

A

Growth and fluid accumulation - increasing pressure

Production of enzymes by the trophoblastic cells

contraction of the blastocyst

ruptures away from the zona pellucida

cells of the blastocyst becomes uncovered and becomes able to implant in the endometrium

126
Q

Trophoblast cells

A

develops from the the outer cells, attaching to the zona pellusida fromt he outside

flattened cells

placenta will develop from them

127
Q

Which cells will the placenta develop from?

A

Trophoblast cells

128
Q

Embryoblast cells

A

Developing from the inner cells

Foetus develops from these

129
Q

Hormone important for maternal recognition

A

Progesterone - luteolysis must be inhibited

130
Q

What happens when corpus luteum produces oxytocin?

A

stimualtes PGF2alpha production by endometrium

t

131
Q

What does the PGF2alpha production depend on?

A

It depends on the threshold number of oxytocin receptors produced by the endometrium

132
Q

What are the requirements for luteolysis?

A

presence of oxytocin receptors in endometrial cells

presence of a critiacal level of oxytocin

PGF2 alpha synthesis by th eendometrium

133
Q

Maternal recognition

A

must occur before luteolysis

no endometrial oxytoxin receptor synthesis

no PGF2alpha production

134
Q

MAternal recognition of pregnancy in ewe and cow

A

the blastocysts secretes IFN-t that blocks the synthesis of uterine oxytocin receptors

135
Q

Maternal recognition in the sow

A

estradiol reroutes PGF2 alpha secreted by the endometrium

136
Q

Maternal recognition of pregnancy of horses

A

the equine conceptus must migrate over the endometrial surface to initiate and complete maternal recognition of pregnancy + 3 protein and estrogens production

137
Q
A