Reproduction 1 Flashcards
What are the 3 steps of normal mammalian sexual development? These steps are also categories of sexual developmental disorders.
Establishment of CHROMOSOMAL sex
Development of GONADAL sex
Development of PHENOTYPIC sex
Bipotential gonad can give rise to…
Female or Male repro-organs
_____ gene promotes ovarian differentiation and development
DAXI
______ gene coding for TDF which upregulates SOX9 expression»_space;> leading to testicular differentiation
SRY
Define Intersex
A general, nonspecific term meaning that ambiguous genitalia are present. Not details on nature or etiology of abnormality.
XXY >
Klinefelter
XO >
Turner
___________ have testicular hypoplasia and almost always are infertile (some may be XXY)
Male tortoiseshell or calico cats
What is a Chimera?
Individual is composed of 2 or more cell populations, each arising from different individuals. This is natural
What is a Mosaic?
Individual is composed of 2 or more cell populations, but the cells originate within the same individual. This usually happens in laboratory experiments
What is the most common example in veterinary medicine?
Freemartin calf - Chimera
What is a freemartin calf/chimera?
Twins- one male, one female. Both share same blood supply in placenta w/ a possibility of cells to exchange into their fetal circulation. This doesn’t have any abnormal effects on the male twin. Female calf twin with have abnormalities within the internal genitalia.
In freemartin calves, the vascular anastomoses between placentas allow male hormones, including ___________ and cells to cross and suppress development of the female genital system.
Mullerian Inhibitory Substance
What are the abnormalities within the internal genitalia in a freemartin?
Small ovaries, blind ended uterus, poorly developed vagina, enlarged clitoris, and seminal vesicles.
T/F:
The male twin is also affected in Freemartin
FALSE! The male twin is minimally affected
What is it called when an ovary and testis are present in the same individual?
True Hermaphrodite
Lateral means…
testis one side, ovary on the other
Bilateral means…
ovotestes both sides. Mixture histologically.
Unilateral means…
ovotestes one side, ovary or testis on other side
True hermaphrodites are rare, but seen more in ____, _____, and _____.
Dogs
Goats
Pigs
Define sex reversal
Animal in which gonadal sex does not follow chromosomal sex. The pathogenesis is not very clear.
Gonad is not the type corresponding to the XX or XY makeup of the individual. It is common to find this Sex Reversal in what two species?
American Cocker Spaniel
Polled Goats
Are sex reversal animals fertile?
NOT FERTILE!!
Is a Pseudohermaphrodite a true hermaphrodite?
NOT A TRUE HERMAPHRODITE!
_______ occurs when chromosomal and gonadal sex agree, but the internal or external genitalia are ambiguous.
Pseudohermaphroditism
Female pseudohermaphroditism is often a result of…
iatrogenic administration of androgens or progestagens during gestation
Male pseudohermaphroditism is due to…
Failure of the mullerian duct regression.
Persistent Mullerian Duct Syndrom is common in…
Miniature schnauzer
XY dog with testes
we may see a penis coming out of vulva
this dog never came into heat
don’t need to do a massive investigation on this p
usually an incidental finding, unless o was looking to breed and p never came in heat
