Reproduction - Again

A closer “real” look at:__________________

_______________ within an ovary___________________ in the uterus

___________________ within an ovary__________________ left in uterus

Mammalogy (Fall 2013 Althoff - reference FDVM Chapter 10)

LEC 08B

Possible additional role of placenta• Most emerging research on this comes from study

of humans and genetically-engineered mice. Using both blood and spinal fluid from human babies to compare hormone profiles between premature and full-term human babies.

• Important for _____________________• Two key hormones identified so far:

a) ___________—helps nerve cells to grow… so impact is beyond maintaining

endometrium b) ___________—protects fetal neurons from becoming overexcited and dying…so impact is beyond contracting uterus & milk letdown

OVARY(stained with haematoxylin and eosin)

GENERAL VIEW

                                                                                                          

1 - cortex2 - medulla3 - area where primordial follicles are located4 - primordial follicles

5 - secondary follicles6 - tertiary follicles7 - mature follicles (Graafian follicles)8 - atretic follicles

Primordial follicle = “not yet spent”, in state of dormancyAtretic follicles = never will matureMature follicles = ready to “erupt”Secondary & tertiary follicles: “between “primordial & mature”

Primordial follicles

Graffian follicle – close to “release”

Ovary with “release” site – will become ______________

Ovary with corpus luteum

Ovary with corpus lutea (plural; _________ is corpus luteum)

Ovary with corpus lutea (plural; singular is corpus luteum)

Buss and Smith (1966) - Elephant CL and CRJournal of Wildlife Management 30:375-388

Corpora lutea&

Corpora _______

Positioning of“implanted”

embryosthat become

fetuses.

“Implanted” = ________________________________________

Site where placenta – fetuswere “connected”…

area heavily pigmented,resulting in

______________________

ovaries

right sideleft side

cervix

Viewbeforehorns

“opened”

ovaries

right sideleft side

cervix

Viewafter

horns “opened”

IUP Hypothesis• IUP = __________________________• Determined to affect a variety of behavior

patterns in female rodents and suspected for non-rodent species that have litter sizes >3

• IUP involves the location of a fetus of one sex with respect to its littermates

• Key results: amount of exposure to ______________________________ ______________________________

__________ = no males either side of her

__________= 1 males on one side of her

_________ = males on eachside of her

OF male

OF male

1F male

2F male

2F male

1F male

IUP Hypothesis…effects• Females exposed to more pre-natal

testosterone may ___________________ _________ than littermates receiving it

• Females more _________________ as littermates including post-weaning

• Female (gerbils) shown to produce more male offspring if 2M females vs. 1M- or 0M-females…2F females produce more female-biased sex ratios vs. 2M females

Carlson N., editor. 1998. ed. Physiology of Behavior. 6th

edition Allyn and Bacon, Boston, Massachusetts

Argente et al. 2003. Journal of Animal Science 81:265-273.

Number of blood vesselsto individual fetuses_________ overall_________ at birth

In summary…• Look for “evidence” of reproductive activity in the

_________• Look for CL (or CR) for evidence of near-full or

full-term pregnancies in the _________ • Look for _______________ for evidence of near

full-term or full-term individual fetuses• ________________, relative to sex of adjacent

fetuses, may affect development and aggressive behavior of females post-partum

• _____________________ at/near a implantation site (of a fetus) can result in increased birth weight for that individual.