Anatomy Lab - Male Reproductive System

Testis

produces spermatozoa and hormones

What hormones do the testis produce?

Testosterone by Leydig Cells

Inhibin by Sertoli Cells

Testicular Capsule

covers the testis with 2 layers

What are the 2 layers of the testicular capsule

visceral vaginal tunic

tunica albuginea

Parenchyma

Seminiferous tubules - site of spermatozoa production

Interstitial tissue - leydig cells are present

Mediastinum

Central connective tissue core

Houses rete tubules

What are the rete tubules in the mediastinum

tiny ducts where the spermatozoa are transported out of the testis

Efferent Ducts

transport spermatozoa from rete tubules to epididymis

Epididymis

site of final spermatozoa maturation (acquire motility and potential fertility)

Reservoir of spermatozoa

Head of epididymis

spermatozoa capacitation

Body of epididymis

spermatozoa capacitation

Tail of epididymis

storage of organ for spermatozoa prior to ejaculation

Epididymal Duct

where spermatozoa transit inside epididymis

Ductus Deferens

Communicates the TAIL of the epididymis to the pelvic urethra

Scrotum

protects the testes and helps with thermoregulation

Inguinal Ring

the passageway from the body cavity into the scrotum

Spermatic Cord

heat exchange

suspends the testis in the scrotum

pathway to and from the body for testicular vasculature, lymphatic

Cremaster Muscle

supports testis and helps with thermoregulation

Pampiniform plexus

vessels’ network

countercurrent heat exchange

What is meant by countercurrent heat exchange in the pampiniform plexus

arteries bring hot blood from body

veins transport cold blood from testis

contact of vessels exchanges the heat

Accessory Glands

produce seminal plasma

Ampullae of Duct Deferens

paired

enlargement of terminal part of ductus deferens

What species is the ampullae of duct deferents absent?

Dogs and boars

Vesicular Gland

secretion is emptied into the pelvic urethra

In what species is the vesicular gland lobulated?

Bull and ram

In what species is the vesicular gland well-developed?

boar

In what species is the vesicular gland elongated with hollow pouches?

stallions

In what species is the vesicular gland absent?

dogs

Prostate Gland

close ti the junction between the bladder and pelvic urethra

has multiple ducts

present in ALL domestic species

What are the 2 structural forms of the prostate gland?

corpus prostate

disseminate prostate

Bulbourethral Glans (cowpers gland)

located on side of the pelvic urethra near ischiadic arch

secretion forms the plug in female reproductive tract

In what species is the Bulbourethral Glans large?

boar

In what species is the Bulbourethral Glans small and buried under bulbospongiosus muscle?

bull

stallion

ram

In what species is the Bulbourethral Glans plug very important?

swine and equine

In what species is the Bulbourethral Glans absent?

dogs

What is the function of the muscles in the male reproductive tract?

protrusion, erection, and ejaculation

What are the 3 muscles of the male reproductive tract?

Urethral muscle

Bulbospongiosus muscle

Ishchiocavernosus muscle

What is the purpose of the penis?

organ of copulation

What are the 2 types of penis?

Musculocavernous

Fibroelastic

What is a Musculocavernous penis?

more cavernous space and less connective tissue

increases in length and girth during erection

Which species have a Musculocavernous penis?

horse and dog

What is a Fibroelastic penis?

less cavernous space and more connective tissue due to sigmoid flexure

What species have a Fibroelastic penis?

ruminants (cattle, sheep, goat) and pig

Boar

Ram

Stallion

Bull

Tom

Bulbus Glandis

caudal part of glans

fills with blood and prolongs the retention of penis during coitus

What species is a bulbus glandis present?

Dogs

Sigmoid Flexure

penis has an S shape when not erected

during erection, sigmoid flexure extends

What species is a sigmoid flexure present?

Bull

Ram

Boar

Glans Penis in a boar

corkscrew-shaped - matches with sow’s cervix

Glans Penis in Stallion

bell-shaped with urethral process

Glans Penis in Tom

glans has spikes to stimulate queens ovulation

Root of penis

the base of the penis

Os Penis

bone is present in the penis

What only species is the Os Penis present?

dog

Filiform Appendage

sprays sperm inside the vagina for a better change of fertilization

What species is a filiform appendage present?

Ram

Prepuce

invagination fold of skin that surrounds the free extremity of the penis

What does the prepuce of the stallion look like?

double-folded

What does the prepuce of the boar look like?

preputial diverticulum presents in the dorsal wall

pheromone that stimulates sows to be immobile during mating