Brainscape's Knowledge GenomeTM

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


See full index

ANSC 355 > Reproduction and sire selection > Flashcards

Reproduction and sire selection Flashcards

1
Q

what has the greatest influence on productivity and efficiency

A

reporduction

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

sheep estrus cycle

A

16-17 days

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

sheep average birth weight

A

2.5-6 kg

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

goat average birth weight

A

2.7-4kg

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

goat estrus cycle

A

19-22 days

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

ovaries

A

-primary organ
-ova production
-estrogen and progesterone production
-multiple ovulations in ewes and does (3-4 ovum)
-where corpus luteum is located

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

oviduct

A

-leads form ovaries from uterus
-ends are funnel shaped (infundibulum)
-cilliated with hairs
-site of fertilization

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

uterus

A

-two horns and body
-inner lining contains caruncles (70-150) (cotyledons attach here)
-muscular layer called myometrium (causes uterine contraction)

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

cervix

A

-neck of uterus
-thick walled and muscular
-closed except at estrus and parturition
-pregnant ewes secretes mucus plug (first indication of birth)

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

vagina

A

-organ of copulation
-tubular in shape
-semen deposited near anterior end
-passageway for fetus at parturition

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

vulva

A

-external genital organ
-passageway for reproductive/urinary system
-vestibule and labia

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

clitoris

A

-erectile organ
-supplied with sensory nerves

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

broad ligaments

A

-supporting tissue/structures
-suspends ovaries, oviduct and uterus

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

mammary glands

A

-produces colostrum and milk
-nourishment and survival of newborn
-two mam glands
-one teat each
-udder supported by suspensory ligament

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

why kind of breeders are sheep and goats

A

-seasonal short day breeders (breeds originating at higher latitudes
-aseasonal breeders (meaning sheep that breed regaurdless of the season (breeds originating in tropical and subtropical environments))
-intermittently polyestrous or completely aseasonal

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

testes

A

-primary organs
-produces sperm and testosterone
-large compared to body size in sheep and goats

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

scrotum

A

-two lobed sac that encloses the testes
-protection
-aids in temp control

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

epididiymis

A

-external duct leading form testis
-sperm transport
-sperm concentration
-sperm maturation
-sperm storage
-appx 100 ft

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

vas deferens

A

-duct from epididymis to urethra
-both vas deferens merge at urethra
-enlarged ampullae
-vasectomy removes part of vas d and makes teaser

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

urethra

A

0duct for both urine and semen
-during ejaculation sperm mixed with accessory gland secretions
-because urine will kill sperm accessory glads prevent

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

male accessory glands

A

-vesicular (seminal)
-prostate (nutrient for semen)
-bulbourethral (cowpers) (neutralizes urine + adds volume)

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

penis

A

-organ of copulation
-sigmoid flexure (s-shaped bend)
-glans penis (free end)
-erectile tissue
-supplied with sensory nerves
-urethral process (sprays semen around vagina)
-prepuce or sheath

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

why do bucks smell

A

-scent glands behind horns-they spray them selves
-can remove scent but does prefer scent

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

why are bucks kept separately from milk does sometimes

A

-bucks housed with milk goats can taint milk
-teaser buck across fence
-doe shows interest buck breeds

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

estrus for ewes

A

-in standing heat
-receptive for 30hr
-needs ram present to show signs
-ewe will seek out ram
-allow male to sniff her
-flagging-of tail to release scent
-slight swelling or redness of vulva
-not all ewes show signs (silent heat)

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

estrus for does

A

-receptive to buck 18-24 hrs
-need buck to show signs
-doe will seek out the male
-flagging (more then sheep)
-swelling of vulval and slight mucous
-bleating
-urinating close to buck

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

ovulation in sheep

A

occurs at the end of estrus
(AI breed 9-12 hrs after onset of estrus)

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

ovulation in goats

A

occurs 12 hrs after the onset of estrus

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

when are ovulation rates highest

A

-during breeding season
-lower during out of season breeding
-ie. more tripplets when breed fall

30
Q

fertilization

A

-union of the ova and sperm in oviduct

31
Q

life of sperm and ova

A

ova=5-8hr
sperm=24hr

32
Q

estrus cycle

A

-time between adjacent estrus
-sheep 16-17d
-goats 19-22d
-hormone regulated
-interrupted by pragnancy

33
Q

male responce to estrus

A

-flehmen response (curl top lip to suck in farmones)
-sniffing ewe/does vulva
-pawing/kicking to see if ewe/doe stands (if fully in heat shell stand)

34
Q

puberty

A

-ewe lambs (depending on breed) 6-10 months, ram lambs 5-6 months
-doeling 6-8 months, buck 3.5 months
-first estrus accompanied by ovulation
-does not mean sexually mature

35
Q

how much should sheep and goat be bread at mature body weight

A

-sheep breed at 70% mature BW
-goats breed at 60% mature BW

36
Q

what is the age of puberty influenced by

A

-genetics
-nutrition
-date of birth (born in june may mature later)

37
Q

anestrous

A

-reproduction inactivity
-three types observed in ewes
-seasonal
-lactational
-postpartum

38
Q

factors affecting fertility in ewes

A

-hereditary
-high fecundity breeds (finnish landrace 3-5, booroola merino 3-5, rideau arcott 2-4, romanvo 3-5)
-normal 1-3 lambs
-low 1 lamb (awassi)
-age of puberty
-age of ewe
-range flocks
-effects of light
-extreme temps
-size of ewe
-nutrition

39
Q

goat fertility

A

they have high fecundity and will have twins and triplets usually

40
Q

age of puberty affecting fertility in ewes

A

-breed as ewe lamb (6-10m) increase lifetime productivity
-dec non productive feed cost
-shortens generation interval
-selection for early puberty
-lambs born in winter/early spring will lamb sooner
-born sept-nov if out of season lambing (might make good replacement because mom bred out of season)
-want ewe lamb to lamb on 1st bday

41
Q

how does age of ewe affect fertility

A

-1 to 8 years
-repo rate grater in 3 y/o
-levels off for 2-3 years
-gradually decreases
-best for ewe lambs to have one big lamb then more

42
Q

range flocks and fertility

A

-have shorter life span

43
Q

what is % lambs weaned influenced by

A

mothering/milking ability

44
Q

effects of light, temp and season on fertility (interaction between all three)

A

-light -> sexual activity
-controlled by light:dark ratio
-breeding season fall ie. light 10-12 hrs
-augus to jan
-peak: October to november

45
Q

how does extreme temperature affect fertility in ewes

A

-affects fertility
-embryo survival
-fetal development
behavior

46
Q

how does sheep size affect fertility

A

-big sheep produce more
-maintenance requirements are higher

47
Q

how does nutrition affect fertility

A

-maintain in good condition
-not fat (2.5-3.4)
-increase lambing % if flushed (ovulate more but need to feed them well through out because they may have triplets
-flushing doesnt work on goats

48
Q

why is sire selection important

A

-rams are half your flock
-selecting good rams will have strong improvements on your flock

49
Q

physical soundness of rams/bucks

A

-pre breeding inspection of rams should include
-four Ts
-teeth, toes, tackle, testes
-good body condition at breeding
-3.3-3.5 ram lamb
-3.5-4 mature ram
-BCS 8 weeks prior to breeding
-after breeding dont forget them
-maintain good body condition and health

50
Q

what are some things that could negatively impact mating

A

-lameness
-impaired vision (wool blindness)
-poor body condition
-rams should be shorn prior to breeding

51
Q

breeding ratios

A

-30-50 ewes per ram
-15-25 ram lambs per ewe
-syncronized flocks 5-10 ewes per ram
-50 does per buck
-lower for buckling

52
Q

hierarchy in rams and bucks

A

-rams fight so dont mix old an new rams during breeding
-old ram will chase new
-they back up and butt heads (can result in broken neck, loss of body condition, paralysis
-rams fight to establish pecking order
-dominant rams mate 12-15x/day
-subordinate rams 2-3x per day

53
Q

how to introduce new rams

A

-buy far enough ahead of breeding to get used to new property
-quarantine for 2-3 wks
-integrate slowly to other rams
-combine at once in a small pen to minimize fighting

54
Q

multi-sire breeding

A

-use odd number of rams
-e.g. three (two fighting, one breeding)
-bucks are more aggressive- may fight all day
-one buck per breeding group

55
Q

large scrotal circumference benifit

A

-bigger testicles (larger circumference)
-more sperm production
-breed more ewes
-ability to produce more offspring
-correlated with age of puberty of female offspring
-highly heritable
-higher testosterone production

56
Q

scrotal circumference size

A

-purebred breeders should select rams with SC >33cm
-ram lambs >30 cm
-bucks no guidlings
-bigger is better
-mature >25cm

57
Q

how can producers know if there sheep have been bred

A

-use raddle paint markers to check for breeding
-marking harnesses (watch for rubbing)
-raddle paint directily on chest

58
Q

how can you extend the breeding season for short season breeders

A

-can use light treatment for out of season breeding
-or select breeds for aseasonality

59
Q

how can hot temperatures affect breeding

A

-hot temps (32 deg cel) damages sperm
-% normal drops
-decreases libido
-serving capacity

60
Q

whats worse immature sperm or fully developed

A

-immature sperm
-infertile for weeks

61
Q

ram selection considerations

A

-health status of farm your buying from
-conformation- size, muscular, head size, full hind quarters
-scrotal circumference
-good feet
-good eyes
-good teeth alined with upper jaw
-born a twin or trip (repo is low heritability so any bit helps)
-good fleece
-testicles
-out of season breeding want rams that dont have seasonality in size of testicles
-prepuce (check for free movement of the penis

62
Q

for ram selection how should you examine testicles

A

-sit him on his rump and palpate testies
-large, firm, equal in size, move freely within scrotum
-tails of epididymis should be well defined
-as well and no lumps in epididymis area

63
Q

brucella ovis

A

-repo problem in rams
-bacterial sexually transmitted disease
-causes epididymitis
-tail of epi becomes hard and swollen
-may affect one of both sides
-vaccine not available in can
-transmission: ram to ram, ram to ewe, ewe to ram
-reduces flock productivity: rams are sterile or less fert, abortions, low conception rates, weak lambs, long lambing season
-rams and bucks

64
Q

scrotal circumference for ram lambs

A

unsatisfactory <26cm
questionable 27-29
satisfactory 30-36
exceptional >36

65
Q

scrotal circumference for rams

A

unsatisfactory <29cm
questionable 30-32
satisfactory 33-40
exceptional >40

66
Q

pizzle rot, sheath rot

A

-inflammation involving prepuce
-extreme cases ram unable to protrude penis
-very painful which results in lack of interest in breeding
-causes:
-feeding excess protein (>16% CP)
-leads to high ammonia in urine
-alkaline- dammaging to tissues
-caused by corynebacterium spp
-rams and bucks

67
Q

cryptorchidism

A

-failure of testicles to descend (one or both)
-both=infertility
-one=reduced fertility
-secondary sexual characteristics due to testosterone
-should not select
-if only one teste affected still fertile but passed on to offspring
-rams and bucks

68
Q

testicular hypoplasia

A

-small testicles
-dont keep
-rams and bucks

69
Q

gynecomastia

A

-rudimentary teats engorged
-testes function normally
-susceptible to mastitis
-cull
-in bucks

70
Q

sperm granuloma

A

-blockage of tubular duct-back up of sperm
-rupture
immune system recognizes as a foreign body
-mass of scar tissue=granulomas
-sterile
-in bucks

ANSC 355 (8 decks)

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