Repro pt 1 Flashcards
Describe the 3 phases of sexual determination.
Phase 1: determination of sex chromosomes (XX or XY)
Phase 2: est. of gonadal type (ovary or testis from bipotent gonad. sex-determining region of Y chromosome/SRY determines testis development)
Phase 3: est. of tubular and external genitalia:
- Anti-mullerian hormone/AMH from Sertoli cells makes male gonad.
- mesonephric tubules: rete ovarii (female), rete testis, efferent ducts (male)
- mesonephric ducts regress in females, paramesonephric ducts regress in males
- paramesonephric ducts = uterine tubes, uterine horns, uterine cervix, cranial vagina
- Mesonephric ducts = epididymis, deferent duct, vesicular gland, ampulla
- urogenital sinus and tubercle = caudal vagina, vestibule, vulva, clitoris in female; prostate, bulbourethral gland, scrotum, penis in males
Disorders of Sexual Development (DSD) replaces antiquated nomenclature. What are these old names and what do they mean?
True hermaphrodite (both female and male gonads) [ovotestes]
pseudohermaphrodite (single gonadal type present which determines the animal’s sex, no matter the remaining parts)
Disorders of sexual development (DSD) can be ____ or ____.
Major or minor
What are the 3 main categories of DSD?
- chromosomal DSD
- XX DSD
- XY DSD
What are chromosomal DSDs?
abnormal # or structure (rare)
chimerism is much more common
What are XX DSDs?
majority are found in “normal” females (XX SRY- ovarian DSD and female phenotype)
What are XY DSDs?
majority are found in “normal” makes (XY SRY+ testicular DSD and male phenotype)
What are examples of chromosomal DSDs that involve an abnormal number or structure of chromosomes? Are they common or rare?
Rare
X__ (Turner-like syndrome) or XXY (Klinefelter-like syndrome)
____ is much more common as a chromosomal DSD. What this is called in cattle?
Chimerism
Freemartinism
What is freemartinism? Which is the freemartin? What happens to the freemartin? What about the other one?
A chromosomal DSD where there are chimeric twins (XX and XY).
The freemartin is the female born co-twin with a male.
The female twin is infertile, the male is minimally affected.
What makes freemartins different from other twins?
In all bovine twin pregnancies, placental vessels from the twins fuse and exchange blood & nutrients.
When the two fetuses are males, this is fine and nothing happens.
When one fetus is a female, the male Anti-Mullerian Hormone (AMH) is exchanged to the female, which makes her a chimera (having both XX/XY chromosomes), which inhibits ovarian growth and favours testicular differentiation.
What the heck is this?!
Freemartins
The functions of the testis and epididymis depends on maintenance of _____ just ____ body _____. A slight _____ will result in testicular ______/_____ and ____ spermatogenesis.
temperature
below
temperature
increase
atrophy/degeneration
decreased
What are the 4 portals of entry into the male repro system and give me an example of each?
Hematogenous localization - Brucella spp.
Ascending infection - Preputial flora
Direct penetration - bite wounds
Extension from the peritoneum - FIP, neoplasms
Tell me why spermatic granulomas exist.
The blood-testis barrier results in spermatozoa being hidden from/foreign to the immune system.
Any injury to the testis or ductular system that exposes the spermatozoa to the interstitial tissue of body results in an severe, granulomatous inflammatory reaction = spermatic granuloma
- What is Cryptorchidism?
- Common or rare? occurs in normal ____.
- inheritance pattern?
- What is the chromosome pattern ?
- location in body?
- unilateral or bilateral?
- incomplete descent of the testis
- most common DSD, normal males
- autosomal recessive inheritance
- XY, SRY + testicular DSD
- anywhere along descent path, but usually close to inguinal canal
- usually unilateral, and side affected varies w/ spp
In Cryptorchidism, the retained testis and epididymus are ____. They are also prone to what 2 things?
hypoplastic
neoplasia & torsion
These are 2 testicles from the same animal. What is your diagnosis?
Cryptorchidism
Why are small testes important, esp in production animals?
dairy sperm output is correlated to testicular weight and vol
big testes = more sperm
What is testicular hypoplasia?
A congenital condition (DSD) in which the testis does not grow to full size at puberty.
What is testicular atrophy/degeneration?
Testes that reduce in size after puberty are called atrophic and the microscopic change is called degeneration
Testicular hypoplasia vs atrophy:
1. are these common or rare?
2. unilateral or bilateral?
3. what is the common end point of atrophy?
- common for both
- can be both for both
- apoptosis of germ cells
What is the gross appearance of a testis that is either hypo plastic or atrophied?
Small, soft, flabby, often yellowish testes which do not bulge on cut surface. Over time they become firmer. white +/- flecks of mineralization.
What are the two types of spermatic granulomas? what are the causes of both?
- spermatic granuloma of the epididymal head (congenital)
- spermatic granuloma in the epididymal tail (secondary to epididymitis)
What is the pathogenesis of spermatic granulomas?
ruptured ducts –> leaked spermatozoa –> body sees extra ductal spermatozoa as foreign –> chronic inflammation –> fibrosis –> obstruction and sperm stasis
What is this lesion?
Spermatic granuloma of the epididymal head
What is this lesion?
spermatic granuloma of the epididymal tail
What is the result of spermatic granulomas?
infertility bc of chronic inflammation
What ism epididymitis? What species does this occur in? What pathology is often seen concurrently with this?
inflammation of the epididymis
rams and dogs
orchitis
Epididymitis:
1. affects which part of the epididymis?
2. unilateral or bilateral?
3. etiology? through which routes?
- tail
- either
- hematogenous (Brucella ovis in rams, Brucella canis in dogs) and ascending infection (Actinobacillus seminis, Histophilus somni in rams, E. coli in dogs)
This is a ram testis. What is the lesion. What is 1 hematogenous route etiology and 1 ascending infection route etiology?
Epididymitis
Hematogenous - Brucella ovis
Ascending infection - Actinobacillus seminis, Histophilus somni
What is the pathogenesis of epididymitis?
Lesion anywhere in the epididymis (which is a single tube) –> obstruction to spermatozoal flow –> rupture of wall –> leakage of spermatozoa –> spermatic granulomas –> leads back to a lesion in the epididymis