Reproduction Flashcards
(125 cards)
1
Q
4 phases of reproduction
A
- Gamete production
- Gamete maturation
- Embryo developement
- Delivery
2
Q
Where do testicles go around time of birth?
A
Descend through inguinal canal and into scrotum
3
Q
Interstitial cells of the scrotum and what they do?
A
Leydig produce testosterone
4
Q
What and where are seminiferous tubules?
A
In scrotum to form sperm cells
5
Q
What does suffix -ules mean?
A
Really small
6
Q
Do birds have a scrotum?
A
NO
7
Q
2 functions of scrotum
A
- House and protect testicles
- Regulate temperature 3-13 degrees cooler than body temp
8
Q
What is heat sterility in sheep?
A
When wool prevents scrotum form keeping testicles cool
9
Q
Are unilateral cryptorchids fertile
A
Yes
10
Q
Are bilateral chryptorchids fertile
A
Lower fertility and less testosterone produced.
11
Q
2 meanings of BSE
A
- Mad cow disease
- Breeding soundness exam (before AI)
12
Q
Why does BSE check for cyrptorchids?
A
Trait is passed down with genetics
13
Q
3 sections of epididymis
A
Head
Body
Tail (at bottom of testicle)
14
Q
3 functions of epididymis
A
Storage for sperm cells (maturation space)
Nutrients for sperm cells
15
Q
What two parts are connected by efferent ductules
A
Head of epididymis and seminiferous tubules
16
Q
What do vas deferens do?
A
Carry sperm cells from epididymis to urethra
17
Q
Define ampulla
A
Large space at end of vas deferens (only some species)
18
Q
What are the 3 accessory glands and how many of each?
A
Seminal vesicle (vascular gland)- 2
Prostrate - 1
Bulbo-urethral (Cowpers)- 2
19
Q
3 functions of accessory sex glands
A
Secrete nutrients
Secrete buffers (b/c sperm cells produce acid when they eat)
Cleans and lubricate urethra
20
Q
2 passageways for urine and sperm
A
Penis: organ of copulation
Urethra: large canal
21
Q
What species have sigmoid flexure?
A
Pigs, cheep, cattle goats
Not in horses
Dogs have bone!
22
Q
What part of male reproductive system produces the most fluid?
A
Accessory glands: seminal vesicle, prostrate, bulbo-urethral (cowper’s)
23
Q
What is the major difference of male bird reproductive system?
A
There are no accessory glands so less semen is produced but it is also more concentrated
24
Q
Where are ovaries located?
A
Just behind the kidneys
25
3 hormones in ovaries and their purpose
1. Estrogen: give female characteristics
2. Progesterone: maintains pregnancy
3. Relaxin: loosens pelvic area during parturition
26
Where is estrogen from?
Growing (graafian) follicles
27
Where is progesterone from?
Corpus leteum, after ovulation/ when follicle collapses
28
2 functions of oviduct
1. Infundibulum (catcher’s mitt)
2. Fertilization -transport zygote to uterus
29
Uterus structure sizes
Large body= 1-2 offspring
Many horns= litters
30
4 functions of the uterus
1. Sperm movement
2. Nourishment -uterine milk
3. Attachment to placenta
4. Contractions during parturition
31
When and how is cervix open/closed?
Open- during estrous- thin mucous
Closed- while pregnant- thick mucous (blocks out bacteria)
32
Compare texture of cervix and vagina?
Cervix= rough connective tissue
Vagina= soft tissue
33
Where is sperm deposited in AI vs. natural mating?
Natural= vagina
AI= bypass cervix
34
2 functions of vagina
Organ of copulation
Birth canal
35
What is the external opening of female mammal reproductive?
Vulva
36
2 Unique features of avian female reproductive tract
1. Only left ovary
2. Follicles in different stages at the same time
37
How long is it and what is formed in the infundibulum of birds?
3 in.
Chalaziferous layer and vitelline membrane
38
How long is it and what is formed in the magnum
15 in.
Most of albumen layers
39
How long is it and what is formed in isthmus?
4 in.
Inner and outer shell membrane
40
How long is it and what is formed in shell gland(uterus)?
4 in.
Secretes shell in 12 hrs.
41
2 functions of avian vagina
1. Secrete substances as cuticle
2. Crypts to catch and store semen
42
How long does it take to form and egg?
25-26 hrs.
(Bird may skip a day to reset with daylight hrs.)
43
Define mitosis
Division of body cells
Asexual= diploid cells
44
Define meiosis
Occurs in ovaries and seminiferous tubules
Sexual= haploid
45
Define spermatogensis
Billions of sperm produced continuously after puberty
46
Define oogenesis and key function
# of eggs set before birth and occurs cyclically after puberty
Conservation of cytoplasm give nutrients for zygote to survive!
47
Biggest difference between spermatogenesis and oogenesis?
1 primary speratocyte= 4 spermatids
1 primary oocyte= 1 ovum (egg)
48
Define pheremones
Volatile chemical products that can trigger mating behaviors in animals of the same species
49
What species deposit semen in the uterus?
Swine and horses
50
What species deposit semen in the vagina?
Most animals: cattle, sheep, goats
51
What animals deposit semen cloaca-vagina and why?
Birds
Males lack organ of copulation
52
Why does sperm life span vary between mammals and birds?
Mammals: couple hours
Birds: (chicken- 10 days, turkey- 30 days) store in vaginal crypts
B/c sperm kept at body temp. In birds
53
How is sperm transported from vagina to uterus?
It’s own motility, tail
54
How is sperm transported from the uterus to oviduct?
Tail and uterine muscle contractions
55
Define capacitation
Acrosome undergoes changes to be able to penetrate zona pellucida
56
Define zygote
Fertilized egg
57
4 things that happen in oviduct
1. Nutrients from egg cytoplasm
2. Free floating
3. Rapid cell division
4. Becomes blastocyst
Before entering uterus
58
What are the 5 extra embryonic membranes?
Yolk sac, amnion, chorion, allantois, allantochorion/ chorioallantois
59
What does the yolk sac do?
Provides early nutrients (uterine milk)
Mammals: degenerates after a few days
Birds: remains as egg yolk
60
What 4 things does the amnion do?
Sac that surrounds fetus
Filled with fluid (“her water broke”)
Protects fetus from shock
Does not fuse with anything
61
Where is the chorion?
Surrounds the amnion sac
62
What does the allantois do?
Grows as told sac degenerates
Takes over absorbing nutrients
Fuses with allantochorion
63
What is the leading case of infertility?
Inability to implant
Often caused by heat stress
64
How far along does implantation complete.
Allantochorion attached to uterus completed 1/3 of way through pregnancy
65
4 types of placenta (only need top 2)
1. Diffuse (sow, mare)= Velcro
2. Cotyledonary (ewe, goats, cow) = buttons
3. Discoid (rodents, primates)
4. Zonary (cats, dogs)
66
What composes cotyledonary placenta?
Cotyledon (allantochorion) fuses with caruncle (uterine wall) to form placentome
67
Where is nutrient from before implantation?
Uterine milk in the yolk sac and allantois
68
Where is nutrients from after implantation?
Mother’s blood supply provides nutrient exchange through placenta
69
What is the gestation period?
Time from conception to parturition
70
3 hormones and their role in parturition
1. Cortisol- from FETAL adrenal cortex, initiates parturition
2. Relaxin- from ovary and relaxes cartilage and ligaments of pelvic area
3. Oxytocin- from posterior pituitary and causes uterine contractions
71
Conditions of bird incubation period.
20-30 days depending on species
100 degrees F
High humidity
72
How is incubation terminated?
By hatching
“Egg tooth” breaks shell
Shell membrane proteins are nutrients for 3 days
Vasotocin: same as oxytocin: from posterior pituitary and causes uterine contractions
73
Production site, target organ, and physiological function of FSH
(Follicle Stimulating Hormone)
From anterior pituitary gland
Target ovaries and testicles
Stimulates Graafian follicles growth and spermatogenesis in seminiferous tubules
74
Production site, target organ, and physiological function of LH?
(Lutenizing Hormone)
From anterior pituitary
Targets ovaries and testicles
Triggers ovulation, CL formation and maintenance, and testosterone production in interstitial tissues
75
Production site, target organ, and physiological function of testosterone?
From testicle
Targets male reproductive tract and brain
Give male characteristics and marking behavior
76
Production site and target organ of estrogen?
From ovary follicles
Targets female reproductive tract, brain, and mammary
77
Eight Physiological functions of estrogen?
1) sexual excitability
2) female characteristics
3) mammary development
4) thicken uterus lining
5) increase blood supply to uterus
6) thin mucus at cervix
7) make uterus sensitive to oxytocin
8) make uterus more resistant to infection
78
Production site and target organ of Progesterone?
From ovary CL
Targets uterus and mammary
79
6 Physiological functions of progesterone?
1) maintain pregnancy
2) mammary development
3) increase growth and blood supply to uterus lining
4) secretion of uterine milk
5) prevent uterus muscle contractions
6) thick mucous by cervix
80
Production site, target organ, and physiological function of GnRH
(Gonadotropin Releasing Hormone)
From hypothalamus
Targets anterior pituitary gland
Triggers release of FSH and LH
81
Production site, target organ, and physiological function of Prostaglandin
From uterus
Targets ovary CL
Causes regress of CL
82
Production site, target organ, and physiological function of cortisol for reproduction?
From FETAL adrenal cortex
Targets dam’s uterus
Triggers beginning of parturition
83
Production site, target organ, and physiological function of Oxytocin?
Produced in hypothalamus
Released from posterior pituitary
Targets uterus
Stimulates uterine contractions
84
How to spell the name of the overall female reproductive cycle?
Estrous Cycle
85
4 phases of the Estrous cycle
1) proestrus
2) estrus
3) metestrus
4) diestrus
86
What is the negative feedback mechanisms to stop Estrous cycle?
Progesterone from uterus tells hypothalamus to stop releasing GnRHs
87
What does it mean when bird eggs follow a hierarchical order?
The largest egg is released first
Based on size
88
Define clutch
A group of eggs that are laid consecutive days in a row
89
3 egg abnormalities
1) soft- shelled- egg laid prematurely, problem with hen
2) thin-shelled- dietary deficiency
3) double yolk- 2 eggs released same time or one egg got lost in infundibulum
90
Seasonal vs. continuous breeders
Continuous (polyestrus): cows, and sows
Seasonal: sheep, mares, birds
91
Sterility vs. Sub-fertility
Sterility: can’t reproduce
Sub-fertility: inefficient reproduction
92
4 causes of sterility or sub-fertility
Anatomical defects
1. Cryptorchid
2. Freemartin
Endocrine malfunction
3. Cystic ovary (can tell by behavior)
4. Persistent CL
93
What is a freemartin
When sterile female is born with male twin
Only cows because happens with shared placenta
94
3 measurements of reproductive efficiency
1. Conception rate (# pregnancies/ # breedings)
2. Number of live births
3. Pregnancy rate (heat detection x conception rate)
95
5 factors influencing fertility
1. Not a fertile male
2. Fertilization failure
3. Early embryonic death
4. Fetal death (rare, except w/ disease)
5. Nutrition, disease, etc.
96
Earliest AI:
First AI in US
1322- horses
1938 in US
97
% of breeding down by AI for turkey broilers, dairy and beef cows, sows and sheep
90% turkey broilers
70% dairy cattle
<10% beef cows
More and more sheep and sows
98
5 reasons to use AI
Breed more females
More genetic progress
More economical
Safety
Disease control
99
4 methods of Semen Collection
1. Artificial Vagina- bulls, stallions, rams, goats, rabbits
2. Hand pressure -boar
3. Massage- poultry
4. Electroejaculation -older or injured
100
Process and result of electroejaculation
Electrical current around accessory glands and semen is less concentrated
101
What three things is semen evaluated on?
1. Volume (young animals produce less)
2. Concentration
3. Motility
102
What temperature is semen stored at?
Fresh: 40 degrees F
Frozen: -312-320 degrees F (in liquid nitrogen)
103
Why dilute semen?
Increase volume
Prolong sperm life
104
What are the diluents?
Nutrient source and buffer
-egg yolk
citrate buffer or tris buffer= Neutralize acid from sperm eating
milk glycerol (prevents ice crystals)
105
What size straws is sperm stored in?
.3-.5 mL straws
106
What is the magic temperature?
40 degrees F
Stored eggs, milk, meat, and sperm here
107
Cattle times of estrus
Estrus lasts 12-18 hrs.
Ovulation 12 hrs. After end of estrus
108
Importance of timing of insemination
Sperm don’t live long in female
Egg and sperm must meet in oviduct
Best from mid to end of estrus
109
Where is semen deposited in each species?
Cattle: in uterine body
Goats + sheep: uterus or cervix
Mare: uterus or last pert of cervix
Poulty: left oviduct
B/c we don’t know which oviduct egg is released from in most animals
110
Estrus detection is each species
Cattle: “standing heat,” barometer, clear discharge, “gomer bulls”
Swine: rigid stance, red swollen vulva
Sheep: sterilized male with marker
Horses: elevate tail, “winking,” frequent urination, tested with stallion
111
6 Factors influencing conception rate
1. Semen quality
2. Receptive female
3. Ability of inseminator
4. Nutritional plane
5. disease status
6. stress levels
112
AI in cats and dogs
Works, but semen storage has lots of unknowns
113
AI in honeybees
Extensive!
114
3 other species where AI is used
Deer, buffalo, endangered species
115
2 benefits of heat synchronization
Reduce labor for heat detection
Helpful to embryo transfer programs
116
Mechanism for heat synchronization
Prostaglandin (brand name Lutalyse)- regresses CL
2-3 days animal will come into heat
117
History of Embryo Transfer (ET)
1st in 1890 w/ rabbits
Today mainly with cattle
118
Process of ET
Donor is superovulated with FSH
Bred with 2 doses of semen
Fertilized eggs flushed from uterus with buffered (saline) solution
Fresh 60% or frozen 50% to recipient
Can sex embryos - use for endangered species
119
Define In-Vitro Fertilization (IVF)
Immature oocytes harvested
mature
Fertilized 20-24 hrs
Cultured 6 days
Shipped 1 week after OPU
120
2 advantages of IVF
Collected anytime- before puberty to recently deceased
121
Order of animal testing for IVF
Rabbits: 1950
Humans:1978
Lands/ calves: 1980
Foals: 1990
122
AI sexing semen
Original: centrifuge
Today: dye and laser (85-95% accuracy)
X chromosome= bigger= more dye
123
4 stages of reproductive life cycle
1. Pre-puberal
primary follicles have been formed
adult behavior developing
2. Puberal
hormones cause reproductive competence
influenced by age and weight
3. Adult
Capacity to reproduce and release gametes maximizes
Female atresia: follicles shrink
4. Senescent
Direct: reproductive lining deteriorates
Indirect: poor nutrition, etc.
124
5 critical nutrients in reproduction
1. Protein- sperm, ova, and epithelial linings
2. Vitamin A- epithelial linings harden without and restrict sperm and ova movement
3. Vitamin E- maintain fertility and immunity
4. Calcium- bird shells
5. Positive energy levels- nutrient hierarchy
125
4 effects of good reproduction
1. More total offspring
2. Less feed, labor, and breeding costs
3. Lower cull rates
4. More total production
