Anatomy and physiology- reproduction (female) Flashcards
what is the vulva
-exterior of female repo tract
-serves as entrance to internal organs
-accommodates passage of urine
what is the vestibule
-general passage to the urinary and repo tract
-extends from the vulva to where urethra opens form bladder
-glands on the wall produce mucous that provides lube during mating
-odors from secretions at the time os estrus have a sexually stimulating effect on the male
what is the phermone
odors from secretions in vestibule at the time of estrus have a sexually stimulating effect on the male
what is the vagina
-female orgam of copulation and birth canal
-located between vestibule and cervix
-in cow and ewe semen is deposited here whereas in mare and sow at least a portion of the semen is deposited in uterus
what is the cervix
-connective tissue with glandular and muscular area
-opening to uterus through which sperm must pass to meet the egg in feertilization
-protects fetus. remains tightly closed
-fetus must also pass through at parturition
what does the uterus consist of
the body and the two uterine horns
what is the fallopian tube or oviduct
-tube that runs form the ovaries to the uterus
-egg travels down tube form ovary to uterine cavity
what are the functions of the oviduct
-carries ovum from the ovary to the uterus
-transport sperm form uterus to infundibulum
-site of fertilization
-fluids secreted provide stable environment for fertilized ovum until it reaches uterus (2-4 days)
what is the ovary
-primary female sex organ
-source of follecle or ova
-source of estrogen which is female sex hormone
what are the functions of the uterus
-site of implantation of embria
-provedes space for the developing embryo or fetus until its ready to live out of the body
-provides nourishment (uterine milk and maternal body supply)
-serves as passageway for sperm on their way form the vagina to the fallopian tubes
what are primordial follicles
the primary sex cells or follicles in the ovaries. they are the fundimental reporductive unit of ovary
what is the ovary like on a sexually immature farm animal
dormant
what happens when a female is at maturity
one or more follicles start to mature
what are mature follicles called
tertiary or graafian follicles
what does the tertiary follicle secret
estrogen which initiates sexual activity in females
how many calves must a heifer wean to recoup her development costs
5-6
what does the age of puberty influence in farm animals
height/size of animal- early puberty stops growth of long bones (plate closure)
what is estrous and estrus
estrous- adjective to describe all things related to estrous
estrus- period of time during estrous cycle where animal is in heat
what is monoestrus
some wild animals such as fox only have one estrus period per year and are known as monoestrus
what is polyestrous
other species have many cycles and are known as polyestrus (pigs, cows)
what are seasonal breeders
only show sexual activity during certian times of year (typically fall for spring birth)
sheep, deer, elk
what are induced ovulators
ovulate on copulation
rabbits and alpacas
what are the phases of the estrous cycles
-proestrus
-estrus
-metestrus
-diestrus
if pregnancy occurs what phase of estrous is prolonged
diestrus
what is estrus
-day 0 of cycle
-period when female is receptive to breeding
-max production of estrogen
-ovulation takes place about 30 hours after behavior signs have ceased
what is metestrus
day 2-4
-starts when estrus ends
-post ovulation period
-the corpus luteum is formed
-develops at cite of ovulation (graafian follicle)
-CL secretes progesterone which prepares uterus for embryo and pregnancy maintenance
what happens when the corpus luteum secretes progesterone
progesterone— negative feedback on Gonadotropin-releasing hormone nurons in hypothalamus— reducing estrogen
what is diestrus
-day 5-17
-the “luteal phase” max size of corpus luteum
-period of non-sexual receptivity
-if pregnancy doest occur:
repo tract goes to less active state and waits for next cycle
-if pregnancy does occur:
embrio signals its presence of the uterus (maternal recognition)
what is proestrus
-d 17-20
-phase before estrus
-follicular growth and rising estrogen levels
-mucosal layer of vagina and uterus multiply
what happens when the mucosal layer of the vagina and uterus occurs
-thickening of the wall of the vagina and increased blood supply to the uterus
-internal repo tract becomes softer or toned in preparation for sperm to transport and fertilization
-happens in proestrus
what hormone controls the estrous cycle
under control of hormones produced by the anterior pituitary gland
what is the follicle stimulating hormone responsible for
stimulates the development of the follicle (ie maturation of a primordial follicle into graafian follicle)
how do follicles grow inder the influence of FSH
-follicles grow under the influence of FSH
-the theca cells of the follicle are stimulated to produce estrogen
-follicles increase in size
-produce more estrogen
-estrogen level reaches a certian point
-results in estrus (heat) and the female will allow the male to mate
what are the functions of estrus
-induce estrogen
-increase uterine motility
-dilation of cervix
-synthesis of cervical mucus
-mammary gland development
-stimulates release of luteinizing hormone
how does luteinizing hormone work
-follicle develops to point that is ready to ovulate
-LH id released from anterior pituitary likely in responce to increased circulating estrogen
-LH causes the wall of follicle to rupture and release the ovum
-ovulation
what is ovulation
ovum is released into the infundibulum of the fallopian tube and starts journey down the reproduction tract
in ovulation what happens to the crater where the follicle ruptured and ovulated
-new tissue begins to develop which eventually develops into corpus luteum
-which secretes progesterone (hormone of pregnancy)
what is corpus hemorrhagicum
blood filled body
what is corpus albicans
white body
what happens with hormones when the follicle ruptures at ovulation
-estrogen levels decline substantually due to loss of theca cells
-female ceases to show signs of estrus
-progesterone feeds back onto pituitary and prevents release of FSH and LH
what is progesterone
-hormone of pregnancy
-facilitates necessary changes in the uterus
-preparation for the arrival of the embryo from the fallopian tube
-implantation of that embryo in the uterus
-if the animal is pregnant, progesterone is secreted through out pragnancy
what are the functions of progesterone
-prevents ovulation
-maintains pregnancy
-causes endometrium to thicken
-increases uterine blood supply
-mammary gland development
what is the hormonal control of estrus cycle in animals who dont get pregnant
-corpus luteum begins to regress in about 12 days
-influenced by secretion of prostaglandins from uterine endometrium (responce to failure of “recognition of pregnancy”)
-regetion of CL decreases progesterone which signals to pituitary to release more FSH to stimulate development of new follicles
what is the hormonal control of estrus cycle in animals who does get pregnant
CL remains functional throughout most of pregnancy
where does fertilization occur
on the upper 1/3 of the fallopian tube
how does sperm make it to the fallopian tube
sperm are propelled due to there own motility
uterine contractions
what is the fertilization life span of an ovum
about one day after ovulation
what part of the ovum must the sperm pass through
the zona pellucida in mammals and the vitelline membrane in non mammals
which is the union with the nucleus of the ovum
when the sperm passes through the zona pellucida what is the ovum now called
a zygote
after the zygote is formed what happens
-it begins to divide mitotically
-by the time the embryo reaches the uterus it. has developed to about the 16 cell stage (2-4 days)
what happens before implantation takes place
the embryo is nourished inside the uterus by secretions of the uterus called “uterine milk”
how long is implantation
it is a gradual process taking a range is 12-60 days in different farm species
what is implantation
three sets of membrane develops around the embryo as it prepares for attachment to the wall of the uterus
what are the three sets of membranes that develops around the embryo
-amnion
-chorion
-allantois
what is the chorion
-the outer most layer of the implantation
-the layer of the embryo that comes in contact with the endometrium
what is the amnion
-fluid filled sac surrounding embrio
-protects the embryo form shock
-connected to embryo by the umbilical cord
what is the allantois
-the third set of membrane for implantation
-extension of the urinary system
-grows out of the umbilical cord and lies between the amnion and the chiron
-webbed with blood vessels
-as pregnancy progresses the allantois increases in size
-liquid waste, gas exchange, nutrition
what is the placenta
it is formed by the fusion of the chorion and the uterine mucosa
what are the functions of the placenta
-transmition of nutrients
-transmission of waste
-protection of fetus
-prevention of infection
-secretions of hormones
what is diffuse placenta attachment
entire surface of membranes are involved in formation of placenta
-horses and pigs
what is zonary attachment of placenta
complete or incomplete band around the fetus
what is discord attachment of placenta
single attachment
primates/rodents
what is cotyledonary attachment of placenta
multiple areas of attachment
ruminants
what happens if an animal retains its plecenta
displaced abomasum, mastitis, ketosis, infection
what is a free martin
-each developing embryo usually has its own set of membranes
-twins in cattle may have an exchange of blood
-where you have a male and female twin
-Y chromosome causes the female to be infertile
-it is the term used to decribe a heifer born twin to a bull calf
what is a way you can detect pragnancy
-absence of heat
-rectal palpation/rectal ultrasound
-biological test by measurement of progesterone, urine, or milk
-ultrasound
-doppler (detects fetal heart beat, and placental+fetal circulation)
what are some signs of parturation
-seeks seclusions
-loss of appetite
-nest building
-increased body temp
-relaxation of vulva
-presents of milk
what are the hormones of parturation
-ACTH (produced by fetus)
-prostaglandin (destroys CL, contractions)
-estrogen (sensitizes uterus to oxytocin)
-oxytocin (stimulates uterine contractions)
-relaxing (relaxes birth canal)
