Reproduction Flashcards
What would happen, if after ovulation, the ovum fails to progress down the oviduct?
Gestational anestrus
What is the role of reproduction in Mother Nature
propagation
What is the role of reproduction in agriculture
efficiency
how to make money in a livestock industry
How important is reproduction
profitability
What is puberty
transition from immature to mature reproductive to hormonal state
How to determine puberty
Age Nutrition Season Health Secondary sexual characteristics
Estrus
period when an animal is receptive to breeding
Estrous cycle
cycle of estrus/anestrus
Gestation
period from conception to birth
Puberty in cattle
8-14 months
Puberty in Goats
4-8 months
Puberty in Sheep
4-8 months
Puberty in Horses
10-12 months
Puberty in Poultry
4-6 months
Puberty in Swine
5-7 months
Puberty in Dogs
5-24 months
Puberty in Cats
4-18 months
Estrus cycle in Cattle
21 days
Estrus cycle in Goats
21 days
Estrus cycle in Sheep
16-17 days
Estrus cycle in Horses
21-23 days
Estrus cycle in Poultry
daily
Estrus cycle in Swine
21 days
Gestation in Cattle
285 days
Gestation in Goats
150 days
Gestation in Sheep
147 days
Gestation in Horses
336 days
Gestation in Swine
114 days
Gestation in Dogs
52 days
Gestation in Cats
60 days
Age at first parturition in Cattle
2 years
Age at first parturition in Goats
1-2 years
Age at first parturition in Sheep
1-2 years
Age at first parturition in Horse
3-4+ years
Age at first parturition in Poultry
16-24 weeks
Age at first parturition in Swine
10-11 months
Age at first parturition in Dogs
8-26 months
Age at first parturition in Cats
6-20 months
Term for parturition in Cattle
Calving
Term for parturition in Goats
Kidding
Term for parturition in Sheep
Lambing
Term for parturition in Horses
Foaling
Term for parturition in Poultry
Laying
Term for parturition in Swine
Farrowing
Term for parturition in Dogs
Whelping
Term for parturition in Cats
Queening
Male Gonad
Testis
Male Gametogenesis
Sperm
Male Steroidogenesis
Testosterone
Female Gonad
Ovaries
Female Gametogenesis
Ovals (eggs)
Female Steroidogenesis
Estrogen
The males role
produce ample quantities of semen
produce sperm + seminal fluids
Seek out receptive female
libido
Mount and Service
Structure- males have to be able to move
Testicles major role
steroidogenesis- testostererone
Gametagenesis- sperm
Scrotum
temperature regulation
-sperm need t be 4-6 degree Celsius below body temp
Epididymis
sperm storage
sperm maturation
transport and concentration of semen
Accessory Glands
Ampulla, Seminal Vesicles, Prostate, Bulbourethral Glands
Accessory Glands Function
Provide nutrients
buffers to fluid to the sperm
Vas Deferens
reproductive ducts from the testes and epididymis
Penis function
copulation (sexual intercorse)
Three type of penis
Fibroelastic‐Sigmoid
Vascular
Os
Fibroelastic Penis (Sigmoid flexure)
S‐shaped retractor muscle
controls extension & retraction of the penis
Animals with fibroelastic penis
Bull, Ram, Board
Vascular Penis
Corpora Cavernosa- Engorges with blood to cause erection
Animals with vascular penis
Horses
Os Penis
Small bone to assist with erection
Animals with Os penis
Found in dogs, cats & primates
Ovaries
production of ovum, estrogen and progesterone
Follicle
structure containing the egg
produce estrogen
Corpus luteum (CL)
structure left after ovulation
produce progesterone
Oviducts
site of fertilization
How does an egg get to the oviduct
during ovulation, the ovary is going to release an egg, picked up by the infundibulum, run the egg down the oviduct
Utures
implantation
nutrient exchange
embryonic to fetal development occurs
What happens if implantation occurs in the oviduct
Fetus will develop, oviduct will eventually erupt causing the offspring and mother to die.
Cervix
store and facilitate sperm transfer
- in some species it can be store up to 5 days
serves as a barrier during pregnancy
Vagina
copulatory
service the birth canal
Where does GnRH go
Into anterior pituitary
GNRH target tissue
Into anterior pituitary
Function of GnRH
stimulate release of FSH and LH
What does FSH stimulate
stimulates follicular growth
Function of FSH
stimulates follicular growth
Where is LH (Luteinizing Hormone) produced
Anterior pituitary
Function of LH
stimulate ovulation and maintenance of CL
LH target tissue
Follicle and Corpus Leteum
Where is estrogen produced
Follicle
Estrogen function
positive feedback to increase GnRH
growth and development of the uterus
responsible for estrus behavior
triggers LH release
Estrogen tager tissue
Hypothalamus
Where is progesterone produce
Corpus Luteum (CL)
What does progesterone does
negative feedback on GnRH
continue LH production
maintains pregnancy
blocks follicle growth
Where is Prostaglandin produce
Uterus
Function of prostaglandin
causes CL regression, which means that fertilization did not occur
Progesterone target tissue
Uterus and Hypothalamus
Where is Inhibin produced in females
Follicle
Function of Inhibin
Triggers LH
Negative feedback to regulate FSH in female and male
FSH target tissue
Follicle
Inhibin target tissue
Anterior pituitary
Hypothalamus produces _______, which stimulates the release of ____ inside the _____________. FSH is going to enter circulation and stimulate ____________ inside the _______. Follicles produce ________. Estrogen will stimulate _______ production, which will send _______ feedback to the anterior pituitary and eventually will cause a switch. Graafian follicle increases estrogen production which stimulates ___ surge. (The bigger the follicle, the more estrogen production, the more Inhibin negative feedback to the anterior pituitary causing a switch will then stop FSH and being producing LH). LH causes ________, which initiates the formation of __________. (Ovum is going to be release, picked up by the infundibulum, and go down the oviduct where remaining of follicle gets converted into CL). CL produces _________. Progesterone is going to feedback the __________ and the ________ and stop ______ production, resulting in a stable state of ___ production. This will allow a chance for fertilization to occur
If the ovary is successful in delivery a fertilized egg, this cycle will happen until parturition. If fertilization does not happen, the degrading egg will send a signal to the _____, which stimulates the release of __________, which will shuts down ___, allowing the cycle to start again.
GnRH, FSH, anterior pituitary, follicle growth, ovaries, estrogen, Inhibin, negative, LH, ovulation, Corpus Luteum, progesterone, hypothalamus, anterior pituitary, GnRH, LH, uterus, prostaglandin, CL.
Stages of the Estrus cycle- Proestrus
CL regression Follicle growth (which increases estrogen)
Stages of the Estrus cycle- Estrus
Causes behavioral change
Prepare uterus to receive embryo
(Estrogen is high, Inhibin is high causing a switch from FSH to LH) causing ovulation
Stages of the Estrus cycle- Metestrus
Cessation of estrus
CL formation- producing progesterone
Stages of the Estrus cycle- Diestrus
Functional CL Period- study state of progesterone production, which will happen indefinitely unit something breaks the cycle.
Prepubertal anestrus
before puberty
Gestational Anestrus
during pregnancy
Postpartum Anestrus
after birth
Lactational Anestrus
Swine- as long as their lactating they are not entering into estrus
Nutritional (Anestrus)
If nutrient availability is low, some animals will not go into estrus.
1) Development of Follicle
2) Secretion of LH
3) Development of CL
4) CL Regression
1) Blister forming- stimulated by FSH- produces estrogen
2) causes ovulation to occur
3) produces progesterone
4) prostaglandin
Follicle Cyst
egg is not released
Nymphomanla
Fix with: Ovulation is caused by GnRH and LH, which causes the cycle
Luteal Cysts
failure to regress Cl
gestational anestrous
Fix with: Prostaglandin
Polyestrous Animals
multiple estrus cycles
Ex: Humans, cattle, pigs
Monestrous animals
one estrus a year
Ex: canines, wolves, bears
Induced Ovulators
estrus is initiated by copulation
Ex: cats
Seasonal Polyestrous Animals
Short days: Sheet, goat, dears
Long Day: horses
Note: Melatonin is produced when is dark
Short days- melatonin stimulates GnRH
Long days: melatonin inhibits GnRH
Need to Properly Match Male & Female
Factors: Genotype Phenotype Environment Breeding Season
Mating Systems
Pasture Mating
Pen Mating
Hand Mating
Artificial Insemination (AI
Estrus Synchronization
All Females Express Estrus at the Same Time
Administration of Reproductive Hormones
PGF2a-Regress CL
Progesterone-“Give and Take”
GnRH-Induces Follicle Turnover & Ovulation
Parturition
- Relaxation of the Cervix
- Offspring Assume Position of Least Resistance
- Uterine Contractions
- Expel Fetus
- Expel “Afterbirth”
What are the signs of ready for parturition
milk
solitary
nervousness
Abnormal calf positions
One limb back One limb retained Head back Backwards Breech Upside‐down Transverse
Note: all of these are dystocia: difficult to give birth