Male Genetalia

Question 1

Secondary sex organs of the male reproductive tract

Answer 1

Paired duct system
Accessory sex glands
Penis
Skin adaptations (scrotum and prepuce)

Question 2

Testis

Answer 2

Primary reporductive organ
Primary site of sperm production

Question 3

What structures are within the paired duct system?

Answer 3

Epididymis
Deferent ducts
Urethra (pelvic, penile)

Question 4

Scrotum position

Answer 4

Dog: horizontal with cr. pole cranially
Tom: vertical with cr. pole ventrally

Question 5

Scrotum

Answer 5

Skin: thin and hairless for heat dissipation
Tunica dartos: smooth muscle with elastic tissue and collagenous fibers
Epididymus

Question 6

During cold & _______, _______ wrinkles

Answer 6

1. Sexual arousal
2. Tunica dartos

Question 7

Scrotum temperature

Answer 7

At about 4-5 degrees Fahrenheit below core body temperature
Hormonal function is NOT affected by temperature

Question 8

Spermatogenesis

Answer 8

All cellular stages involved in the production of sperm (mitosis and meiosis)
Spermatogonia to sperm

Question 9

What is the clinical significance of gubernaculum regression?

Answer 9

Cryptorchidism, if not removed could turn into a tumor

Question 10

What are the borders of the deep inguinal ring?

Answer 10

Medial: Rectus abdominus
Caudolateral: Inguinal ligament
Craniolateral: Internal abdominal oblique

Question 11

Pampiniform plexus

Answer 11

Cooling of blood by absorption of heat from vein
Absorption of pulsation (systolic-diastolic) pressure in artery

Question 12

Coverings of the testis

Answer 12

1. Tunica albuginea testis: covers the immediate surface of the testicle (DRCT)
2. Visceral Vaginal Tunic (mesothelium)

Question 13

How is the tail of the epididymus attached to the cd. pole of the testicle?

Answer 13

By the proper ligament of the testicle

Question 14

How is the epididymus attached to the parietal vaginal tunic?

Answer 14

Via the ligament of the tail of the epididymus

Question 15

What are the proper ligament of the testicle and ligament of the tail of the epididymus?

Answer 15

Remnants of the fetal gubernaculum testis

Question 16

How is the vaginal tunic attached to the skin?

Answer 16

Scrotal ligament

Question 17

Seminiferous tubule

Answer 17

Rete testis
Efferent ducts

Question 18

Epididymus

Answer 18

Head, body and tail
Long coiled tube, interconnecting testicle with ductus deferens
Site of final maturation and storage of sperm

Question 19

Spermatic Cord

Answer 19

Testicular vessels, nerves and lymphatics
Ductus deferens
Vaginal tunic (serous membrane wrapped around)

Question 20

Where does the r. testicular vein drain?

Answer 20

Directly into the cd. vena cava

Question 21

Left testicular vein

Answer 21

Drains into the l. renal vein
Ruptured by pulling too hard during neuter, causes internal bleeding and hemoabdomen

Question 22

Testicular lympahtic drainage

Answer 22

Testicle drains directly into the medial iliac lymph node

Question 23

Testicular thermoregulation

Answer 23

Structures involved are the cremaster muscle (skeletal), tunica dartos m. (smooth) and the pampiniform plexus

Question 24

Penis

Answer 24

Primary copulatory organ
Urethra for ejection of urine and semen
Prepuce

Question 25

What is the structure of the penis?

Answer 25

Root, body and glans penis (bulbus glandis, pars longa glandis) Corpus cavernosum penis (erectile tissue) Tunica albuginea penis

Question 26

Tunica Albuginea penis

Answer 26

Tough CT allowing for increased length and diameter of the penis during erection

Question 27

Copus Cavernosum Penis (CCP)

Answer 27

Cd. end splits into 2 crura Anchored to an ischial tuberosity

Question 28

What is the CCP surrounded by?

Answer 28

A pair of ischiocavernosis muscles (contraction compresses "stiffen" the penis)

Question 29

CCP ossification

Answer 29

The distal 3-4 inches of the CCP is ossified in the dog to form the baculum (os penis) Tom has a poorly developed baculum (~1/4 inch)

Question 30

Other than the CCP what erectile tissue doe the penis have?

Answer 30

Corpus spongiosum penis Corpus spongiosum glandis (bulbus glandis, pars longa glandis)

Question 31

Corpus spongiosum penis (CSP)

Answer 31

Begins as a pair of bulbous enlargements to either side of the urethra just below the anus Penile urethra Covered with bulbospongiosus m.

Question 32

How does the CSP extend?

Answer 32

Distally as a single tube of erectile tissue completely surrounding the penile urethra

Question 33

Bulbus glandis

Answer 33

Proximal ring-like Expansion of CSP(venous sinuses and elastic tissue) Surround os penis

Question 34

How is the bulbus glandis separated from the pars longa glandis?

Answer 34

By CT septum

Question 35

Pars longa glandis

Answer 35

Distal elongated part of the penis Forms the apex of the penis

Question 36

Coital Tie

Answer 36

Male dog dismounts, turns around, lifting one hind-limb over the female and the animals stand facing opposite directions

Question 37

What is the function of spasmodic contractions?

Answer 37

Send pulses down the CSP and forces semen down and out of the urethra

Question 38

Tom cat's penis

Answer 38

Caudally directed penis (flaccid state) Cranially directing during copulation Penile spines (on glans penis) to assist with maintaining intromission (not neutered)

Question 39

Urine Spraying in cats

Answer 39

Behavioral problem Territorial marking Becomes a problem when tom chooses household objects for marking (smell)

Question 40

Posture of the tom during urine spraying

Answer 40

Standing position with tail erect Hindquarters directed toward object Ears caudally directed

Question 41

Clinical consideration of the urethra for dogs

Answer 41

Canine Urethral obstruction Urethral Calculi

Question 42

Clinical consideration of the urethra for cats

Answer 42

Tom Feline Urologic Syndrome Urethral Plug

Question 43

What is derived from the internal pudendal?

Answer 43

Artery of the penis

Question 44

Dorsal artery of the penis

Answer 44

Nutritional supply

Question 45

What does the deep artery of the penis supply?

Answer 45

Supplies CCP for erections

Question 46

What does the artery of the bulb supply?

Answer 46

Supplies CSP for ejaculation

Question 47

Pelvic nerves

Answer 47

Parasympathetic- S2 and 3 (vasocontrol to engorge penis) Assists in relaxing helicine vessels and increasing CCP blood flow (erection)

Question 48

Hypogastric nerves

Answer 48

Sympathetic- L1-L4 (ejaculation)

Question 49

Pudendal nerves

Answer 49

Somatic- S2 and 3 Innervates the striated muscles (ejaculation)

Question 50

Dorsal nerves of the penis

Answer 50

Sensation to the glans penis

Question 51

Prepuce

Answer 51

Sheath of skin surrounding and protecting the penis Outer lamina haired, inner lamina with delicate skin Fornix Preputial ostium and cavity

Question 52

What are the accessory sex glands in the dog?

Answer 52

Prostate and ampullary glands

Question 53

Prostate

Answer 53

Around proximal urethra R. and l. lobes

Question 54

What are the accessory sex glands in the cat?

Answer 54

Prostate and the bulbourethral gland

Question 55

Clinical consideration of the prostate?

Answer 55

Benign prostate Hyperplasia

Question 56

Prostate Hyperplasia

Answer 56

Press on large intestine (rectum) Producing constipation and difficulty in defecation Treatment: castration (surgical removal)

Question 57

What are the extrinsic muscles of the penis?

Answer 57

Ischiocavernosus m. Bulbospongiosus m. Rectractor penis m. Ischiourethralis m.

Question 58

Retractor penis m.

Answer 58

Pair of smooth m Arise from the sacrocaudal spines, pass around the anus, and attach half way down the penis