Brainscape's Knowledge GenomeTM

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


See full index

Reproductive Pathophysiology > Section 2: Bovine > Flashcards

Section 2: Bovine Flashcards

1
Q

describe the bovine uterus

A

binornual with a short body

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

how many caruncles does the normal bovine uterus have?

A

70-120

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

how does the uterine tone change in estrus and diestrus?

A

estrus: turgid
diestrus: more flaccid

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

do cows have a suburethral diverticulum?

A

yes

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

how many annular rings does the bovine cervix have?

A

4-5

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

does the bovine cervix tone change appreciably during the estrous cycle?

A

no
more open during estrus

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

what does the vagina of the bovine extend between?

A

from fornix with external os of cervix to vestibule with urethral orifice and suburethral diverticulum

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

in the bovine uterus, the ____________________ is caudal to the external bifurcation

A

internal bifurcation

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

what is the size of bovine ovaries?

A

1cm in quiescent
5 to 6cm in cows with cysts or large corpus luteum

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

what are the four palpable characteristics of the corpus luteum?

A

size
irregular shape
waist
crown

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

what is puberty defined as in heifers?

A

first behavioral estrus accompanied by spontaneous ovulation and a normal luteal phase

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

when do dairy heifers usually reach puberty?

A

10-12 months

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

what estrous cycle do cattle have?

A

non-seasonally polyestrous

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

what is the normal estrous cycle length in cattle?

A

18-24 days
average 21 days

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

what are the four stages of the estrous cycle?

A

proestrus
estrus
metestrus
diestrus

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

in which stage of estrous will a cow stand to be ridden?

A

estrus

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

when does ovulation occur?

A

10-15 hours after the end of estrus

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

what is the metestral “bleed off”?

A

second or third day post-estrus petechial hemorrhage in endometrium

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

when do follicular waves occur?

A

2-3 per estrous cycle
heifers more apt to have 3
continue during pregnancy

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

what type of placenta do ruminants have?

A

synepitheliochorial placenta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what produces progesterone throughout pregnancy?

A

corpus luteum
placenta can maintain pregnancy 150-250 days gestation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

at what point can the placenta maintain pregnancy in ovariectomized cows?

A

150-250 days gestation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

when does the fertilized egg or zygote enter the uterus?

A

3 to 3.5 days after ovulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what is the average gestation length in cows?

A

280 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

when does maternal recognition of pregnancy occur in cattle?

A

16-17 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

what is parturition induced by?

A

signaling from maturing fetal hypothalamic-hypophyseal-adrenal axis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

what is a major sign of impending parturition in cows?

A

relaxation of the pelvic ligaments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

what is stage I of labor?

A

dilation of cervix

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

how long does stage I of labor take?

A

2-6 hours
may approach 24 hours in primigravid heifer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

what is stage II of labor?

A

fetal expulsion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

how long does stage II of labor take?

A

2-4 hours
heifers can go longer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

how long is the pituitary insensitive to gonadotropin releasing hormone postpartum?

A

8-10 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

when will uterine involution be histologically complete?

A

about 45 days postpartum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

what is uterine involution indicative of?

A

female’s ability to become gravid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

what type of penis do bulls have?

A

fibroelastic penis
has sigmoid flexure

36
Q

what accessory sex glands do bulls have?

A

seminal vesicles
prostate
bulbourethral glands
ampulla

37
Q

when are bulls usually sexually mature?

A

9-10 months

38
Q

what is the definition of puberty in bulls?

A

can intromit and produce an ejaculate containing 50 million spermatozoa with at least 10% progressive motility

39
Q

what is the volume of average ejaculate of a bull?

A

5-8 ml

40
Q

how many spermatozoa are in an average bull’s ejaculate?

A

5-15 billion spermatozoa

41
Q

what is indicative of a yearling bull’s sperm output and to some extent its fertility?

A

scrotal circumference measurements

42
Q

bulls are attracted to cows displaying ______________________________________________

A

estral homosexual mounting behavior

43
Q

what is the breeding weight of holsteins?

A

750-850 lb at 49-51 inches at the withers

44
Q

when do most dairies target breeding?

A

14-15 months

45
Q

what is the goal of breeding heifers at 14-15 months on dairies?

A

to have a holstein heifer calve at 1250-1300 lb at 24 months

46
Q

what are breeding recommendations based on?

A

weight and height at withers (body frame)

47
Q

what are the two categories for estrous detection?

A

observation
heat detection aids

48
Q

what is the primary sign of estrus?

A

cow standing to be mounted by other cows

49
Q

are secondary signs of estrus more or less reliable than primary signs?

A

less reliable

50
Q

what is the optimum time period to inseminate cows?

A

mid-estrus to 6 hours post estrus

51
Q

what is the process of daughter proven sire for choosing bulls?

A

a bull sires 40 daughters
milk production records of daughters compared, only those that were good enough kept as AI studs
takes 4-5 years

52
Q

what is used now to select young bulls?

A

genomic proven sire
young bulls genotypes through DNA analysis

53
Q

what is semen from AI bulls evaluated for?

A

morphology
motility
concentration
volume

54
Q

what is the goal of cow/calf operators?

A

45-60-day calving season

55
Q

when bulls are put into herds, how many cows per bull are there?

A

25-40 cows per bull

56
Q

what are some factors that affect cows’ fertility?

A

nutrition
lactational anestrus
infectious disease

57
Q

why do beef cows experience lactational anestrus?

A

suckling inhibition of luteinizing hormone

58
Q

what are the ovarian structures?

A

stroma
follicles
corpus hemorrhagicum
corpus luteum
corpora albicantia

59
Q

what is the first behavioral estrus at puberty preceded by?

A

increase in the frequency of luteinizing hormone pulses leading to ovulation with resulting short lived rises in progesterone

60
Q

if there is a corpus luteum present and progesterone levels are high, what happens to the dominant follicle?

A

undergoes atresia

61
Q

what does prolonged exposure to progesterone in the luteal phase result in?

A

down regulation of endometrial progesterone receptors and increases in endometrial estrogen receptors

62
Q

in what stage does estrogen climb to the peak?

A

proestrus

63
Q

what are hormones doing in metestrus?

A

estrogen drops
progesterone rises

64
Q

what are hormones doing in diestrus?

A

progesterone high
estrogen has slight rise with follicular waves

65
Q

what are hormones doing in estrus?

A

estrogen declining
luteinizing hormone peak

66
Q

when does placental attachment occur?

A

begins 30 days after ovulation
complete by 45 days

67
Q

what are the connective tissue changes leading up to parturition thought to be due to?

A

relaxin from bovine corpus luteum

68
Q

is dystocia more prevalent in dairy or beef cattle?

A

dairy cattle

69
Q

what is the rate of dystocia in heifers?

A

30-60%

70
Q

why do beef cattle have lactational anaestrus?

A

suckle stimulus

71
Q

what has a significant impact on resumption of postpartum cyclicity?

A

energy balance

72
Q

how long does it take a bull to ejaculate?

A

1.3 seconds

73
Q

how many days is most profitable to have a cow milking and not?

A

305-335 days milking
40-60 days not

74
Q

what is the optimum calving interval?

A

12-13 months depending on milk production

75
Q

why does the voluntary waiting period exist?

A

uterine involution takes 30-45 days
breeding at estrus prior to uterine involution results in very poor conception/pregnancy rates

76
Q

what are some heat detection aids?

A

pressure mount devices
paint sticks
activity monitors
video camera

77
Q

how long does fertile semen live after being thawed?

A

24 hours

78
Q

what is added to semen before it is frozen?

A

extender: egg yolk, milk, or soy based
glycerol: protects sperm against freezing damage

79
Q

when can a cow be diagnosed with pregnancy?

A

day 28: transrectal ultrasound
day 30: palpation
day 35: chorioallantoic membrane can be palpated

80
Q

what does the dominant follicle’s increasing estrogen trigger if there is no corpus luteum present?

A

luteinizing hormone surge
ovulation

81
Q

for what portion of pregnancy does the corpus luteum produce progesterone?

A

whole time
placenta can maintain 150-250 days

82
Q

what is the prevalence of dystocia in mature cows?

A

2-8%

83
Q

when can the first ovulation occur after parturition?

A

20 days postpartum

84
Q

when does the first ovulation after parturition usually occur in beef cattle?

A

60 days postpartum

85
Q

why do beef farmers wait to rebreed their nursing cows until their calves are less dependent on nursing (2-3months)?

A

lactational anestrus due to suckling inhibition of luteinizing hormone

Reproductive Pathophysiology (12 decks)

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