Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Artificial insemination and reproduction I > Spermatogenesis, heat cycle > Flashcards

Spermatogenesis, heat cycle Flashcards

1
Q

Production of normal numbers of fertile
spermatozoa requires: (4)

A

– Endocrine regulation of the testis
– Mitotic divisions of spermatogonia

– Meiotic divisions resulting in haploid
spermatids
– Morphologic transformation of spermatids into
spermatozoa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

where is GnRH recreted from

A

gondaotropin releasing hormone from the hypothalamus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

FSH and LH secretion from

A

the anterior lobe of the pituitary / adenohypophysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what cells produce spermatozoa?

A

leydig cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

testes are composed largely of

A

seminiferous tubules—coiled tubes, the walls of which contain cells that produce sperm, leydig cells.

Seminiferous tubules may constitute up to 90 percent of the testis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

precursor to testosterone in the testes

A

progesterone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Steps of Development of primary gametes in males (5)

A

Prespermatogenesis
Spermatogenesis
Spermatocytogenesis
Meiosis
Spermiogenesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

duration of spermatogenesis

A

approx. 30- 75 days dependent upon species
so roughly 2-3 months

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what do the sertoli cells protect spermatozoa from?

A

the bodies own immune system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Semen ingredients

A

Spermatozoa & Seminal plasma/fluid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Seminal plasma is produced by (3)

A

Accessory sex glands
Epididymis
Ampullary gland

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the accessory organs of the male?

A

paired ampullary glands
vesicular glands
prostate gland
bulbourethral glands

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

another name for bulbourethral gland and in which species missing and in which, well-developed

A

Cowper’s glands

absent in ca, well developed in su

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

seminal plasma purposes (5)

A

Optimal osmotic pressure
Constant pH
Dilution of spermatozoa
Transport media
Stimulates sperm transport in female reproductive tract

Not important for fertility.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

in which species is the prostate absent and in which, well developed

A

absent in eq, well developed in car

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

paired vesicular glands contribute what percentage of seminal plasma and contains what?

A

60%, fructose, ascorbic acid,
prostaglandins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what stimulates sperm to begin to swim?

A

mixing with seminal plasma enzymes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Prostate gland contributes what percentage to seminal plasma and contains what imporant component?

A

5-6 % for bulls

33% enzymes for sperm activation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what component of seminal plasma do the Paired bulbourethral glands contribute?

A

viscous secretion for lubricating female reproductivetract and provides gel fraction in the boar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

duration of spermatogenesis

A

man 75 days
bull 61 days
stallion 55
ram 47
boar 39

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

estrus cycle is divided into either

A

2 or 4 parts

luteal/follicular or

pro-, estrus, met-, di-

21
Q

when estrus is divided into two, what are the two parts:
which one takes up a larger portion of the cycle?

A

luteal or follicular phase

follicular phase is shorter (approx. 20%)

(corpus luteum development and follicular development)

22
Q

name the stages of the estrus cycle

A

proestrus 18-21 days
estrus 1-2 days
metestrus 2-5 days
diestrus 5-18 days
(anestrus e.g. during pregnancy)

the days here apply to bovine

23
Q

how quickly after calving does a cow begin to cycle again

A

2-3 months

“Mature cows usually take about 60 days to come on heat again after calving; young cows may take 90 days or more.”

24
Q

how quickly after foaling do mares begin to cycle again

A

Postpartum mares will have a “foal heat” 7 to 14 days following foaling, and a second cycle approximately 30 days later. Breeding on foal heat is still somewhat of a controversial practice.

25
Q

how quickly after farrowing do sows begin to cycle again

A

sows experience lactation anestrus

factory farmed piglets are weaned at approx. 21-28 days old

after weaning the sows typically come into heat again in 3-5 days

26
Q

how quickly after lambing do sheep begin to cycle again

A

the following autumn

Ewes are seasonally polyestrous, cycling every 16–17 days during the breeding season.

27
Q

in which month of gestation does the CL regress in equine

A

3-5 months as the placenta begins to produce progesterone

“Individual CL appear to regress at different times in the same ovaries of individual pregnant mares after Day 100 of gestation.”

28
Q

features of proestrus (3)

A

growth of preovulatory follicles
increase in estrogen, estradiol peak at end of proestrus
endomtetrial development

29
Q

features of metestrus (5)

A

in cows ovulation occurs during metestrus, not estrus like in other species

estrogens go low
corpus hemorrhagicum develops
uterine contractions and some vaginal bleeding can occur

fsh stimulates follicular growth

30
Q

features of diestrus (4)

A

is longest period of cyclicity.

progesterone is high
FSH develops 2nd wave follicles
no uterine contractions

involution of CL if no pregnancy -> release of PGF2alfa

31
Q

why do bovine experience some vaginal bleeding during metestrus

A

estrogen withdrawl’s effect on blood vessel permeability, is considered physiological.

17-18 days post bleeding, heat should occur again (full cycle is 21 days)

32
Q

how long does a CL persist in bitches?

A

2 months ish

33
Q

length of estrus in dog

A

five to nine days

many sources say up to 2 weeks but that includes proestrus which is difficult to diffrentiate from estrus

dogs ovulate an immature oocyte

33
Q

what estrus phase is unique to cats?

A

“postestrus”

because cats are induced ovulators

34
Q

cat gestation duration

A

58-60 days
other sources say 63-65 days

35
Q

How soon after giving birth can a cat go into heat?

A

Most queens will return to estrus about 4 weeks after weaning their kittens if it is still the breeding season.

However, it is entirely possible for a queen to return to estrus while still nursing.

36
Q

horse gestation

A

11 months
(10-12)

37
Q

name 3 polyestrus animals

A

sow
cow
cat (or seasonally)

38
Q

name seasonally polyestrus long day breeder

A

horses begin to come intro estrus as days grow longer in the springtime.

(so foals are typically born the following spring)

39
Q

name a seasonally polyestrus short day breeder

A

sheep begin to come into estrus as days grow shorter in the autumn

(so lambs are born the following spring, approx. 5 months later)

40
Q

name 3 monoestrus animals

A

dog wolf bear

(even thought some dogs may cycle twice per year)

41
Q

what percentage of spermatozoa is typically ‘imperfect’

A

approx. 20%

42
Q

how are spermatozoa defects classified

A

primary
secondary
tertiary

43
Q

seasonally polyestrus species cycles are regulated by what hormone

A

melatonin

44
Q

ewe estrus cycle length?
duration of heat?

A

17 days
24-36 hours

45
Q

mare estrus cycle length?
duration of heat?

A

21 days
3-8 days

46
Q

sow duration of heat?

A

48-72 hours

47
Q

bitch duration of heat?

A

9 days

(same goes for queen)

48
Q

when might cows experience bloody vulvar discharge?

A

1-4 days after heat and approx. 18 days before next ovulation (?)

due to estrogen’s effects on vaginal membrane permeability.

49
Q

when are cows typically inseminated afetr parturition?

A

50-55 days after parturition

some variation can occur of course, but 3 months is considered too long and insemination at the first post-parturition heat is a bit too soon.

Artificial insemination and reproduction I (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions