Male Anatomy

Where does the spermatic cord begin?

At the abdominal ring where its constituents come together

Where is the tail of the epididymis located?

At the opposite end of the testicle from head

What happens during an erection of the penis?

It becomes engorged with blood (more blood enters penis via arteries than leaves via veins)

Where is the deep fascia located?

Just superficial to the common vaginal tunic of the testicle (the outer layer of peritoneum covering the testicle)

What are examples of secondary sex characteristics associated with masculinity?

-Massive head and shoulders in bull -Well developed jaws and crest in stallions -Horns in some breeds of rams -Tusks in boars -Less subcutaneous fat -Poorer marbling of muscle

What does the spermatic cord consists of?

-Testicular artery -Testicular veins -Lymphatics -Nerves (sympathetic) -Ductus deferens (vas deferens) -Internal cremaster muscle (smooth muscle) -Visceral layer of tunica vaginalis (proper vaginal tunic)

What is the purpose of castration?

-To prevent the reproduction of inferior animals -To improve the quality of animals used for food -To produce a more docile animal

What is the deep fascia derived from?

3 abdominal muscle

What is the epididymis?

A long convoluted tube

What type of tissue is the tunica dartos?

A mixture of connective tissue and smooth muscle

What is a cryptorchid testicle?

A testicle that fails to descend into the scrotum

What does the visceral layer of the proper vaginal tunic do?

Acts as an envelope and covers the testicle and cord that is an extension of the peritoneum cavity

What does the prostate gland produce?

An alkaline secretion

What is a high flanker animal?

An animal in which testicle descends into the inguinal canal/ring but not into the scrotum

What is a cryptorchid animal?

An animal with a cryptorchid testicle

What is a monorchid animal?

An animal with only one retained testicle

Why are cryptorchids usually sterile?

Because body temperature is too high for normal spermatogenesis

Where is the tunica albuginea located?

Beneath proper vaginal tunic

Where is connective tissue in the testicle?

Between seminiferous tubules

Where is the superficial fascia?

Between tunica dartos and underlying deep fascia

When is the descent of the testicles complete?

By birth or soon after

What does the connective tissue in the testicles contain?

Cells of Leydig

What does the tunica dartos do?

Contracts and relaxes according to climatic conditions

What is the scrotum?

Cutaneous sac which contains the testicles

What part of the testicle produces sperm?

Cytogenic

What happens to the tunics of the testicle when it passes into the scrotum?

It becomes enfolded in parietal peritoneum

What does the tail of epididymis connect with?

Directly to the vas deferens

What is free end of the penis shaped like in a boar?

Distal portion of boar's penis is corkscrew shaped

What is the scrotal septum?

Divide scrotum into two compartments (one for each testicle)

When is an inguinal hernia prone to happen?

During an act of breeding

What is the internal inguinal ring formed by?

Edges of muscles and tendons

What dos the head of the epididymis connect with?

Efferent ducts

What does the epididymis connect?

Efferent ducts with the vas deferens (ductus deferens)

Where are the bulbourethral glands located?

Either side of pelvic urethra just caudal to other accessory glands

What part of the testicle produces hormones?

Endocrine

What is free end of the penis shaped like in a horse/ram?

Free portion of urethra (urethral process) projects beyond the glans

What is free end of the penis shaped like in a bull?

Helmet-shaped gans - galea glandis

Where are the testicles located?

In scrotum outside abdominal cavity

Where do testicles originate?

In the sublumbar region immediately caudal to the kidneys

How are the testicles positioned in stallions?

Long axis nearly longitundinal

How are the testicles positioned in bulls and rams?

Long axis perpendicular to ground (vertical)

How are the testicles positioned in boars?

Long axis upward and backward

What type of tissue is the superficial fascia?

Loose connective tissue

What is the interior of the testicle?

Masses of seminiferous tubules

How is the testicle shaped in the bull?

More elongated

Where does the crura originate?

On caudal surface of ischial arch, one on each side of symphysis of pelvis

How is the testicle shaped in most species?

Ovoid (egg shaped)

Where is the body of the epididymis?

Parallel to the long axis of the testicle

What is the inguinal canal?

Passageway from the abdominal cavity to the exterior

What is the corpus cavernosum?

Primary erectile tissue

What does the testicle do?

Produce and transport sperm

What is the function of the ductus deferens?

Propels sperm from epididymis to ejaculatory duct in the prostatic urethra at the time of ejaculation

What is the relative testicle size according to body weight and size?

Ram > Bull > Stallion >/= Boar

What is the testicle size in rams?

Relatively larger than a bull

What is the testicle size in bulls?

Relatively larger than a horse

What is castration?

Removal of the testes of the male

What is a risk of cryptorchidism?

Retained testicle may become tumorous

What does the tunica albuginea give rise to?

Septa

What type of membrane in the proper vaginal tunic?

Serous membrane

What is the function of the epididymis?

Serves as a place for spermatozoa to mature prior to the time they are expelled by ejaculation Serves as tubule of transport of sperm from area of formation (seminiferous tubules)

What is the external inguinal ring formed by?

Slit in aponeurosis of one of the abdominal muscles

Retained testicles are often what?

Smaller and softer than normal

What is the danger with an inguinal hernia?

Strangulation of a loop of gut

Where is the corpus spongiosum?

Surrounds urethra- erectile tissue

What does the body of the epididymis connect with?

Tail of epididymis

What is the structure of the tail of the epididymis like?

Takes a 180 degree turn and runs back along the body of the epididymis

Why can't normal spermatogenesis occur in the abdomen?

Temperature is too high

What are the primary orangs of reproduction in the male?

Testes

What does the reproductive system for males consist of?

Testicles, epididymis, scrotum, ductus deferens, accessory sex glands, penis, and prepuce

What do the cells of Leydig secrete?

Testoterone

What is the gubernaculum testis?

The fibrous cord

What does the ductus deferens pass through after leaving the tail of the epididymis?

The inguinal canal as part of the spermatic cord

Where does the inguinal canal extend from?

The internal inguinal ring to the external inguinal ring

What does the prostate gland surround?

The pelvic urethra

What does the tunica dartos form in the scrotum?

The scrotal septum as it passes on the median plane

What does the efferent ducts pierce?

The tunica albuginea

What does the crura converge for?

To form body of penis (corpus penis)

Where does the head of the epididymis attach?

To the same end of the testicle that blood vessels and nerves enter

What divides the parenchyma (the testicle) into lobules?

Trabeculae

What is the ductus deferens?

Tubule for transport of sperm. It is a muscular tube of smooth muscle that extends from tail of epididymis to the pelvis part of the urethra

What are efferent ducts in the testicle?

Tubules from seminiferous tubule to epididymis

Where does the Trabeculae extend from?

Tunica albuginea

How many roots (crura) does the penis have?

Two

What is Mediastinum testis formed by?

Uniting of trabeculae in the center of the testicle

What is an inguinal hernia?

Usually a loop of bowel

Where is the urethra located in respect to the corpus penis?

Ventral to the body

The right and lest testicle are. . .

paired glands