Week 2 - Carnivore Internal Genitalia

What is the parenchyma of the testes?

The tissue of the testis

• contained in capsule under pressure

• soft, yellow-brown in color

What are the parts of the epididymis & what is its function?

Parts:

• Head

  • Attached to testicular capsule

• Body

  • loosely attached to surface of testis

• Tail

  • attached to testis by proper ligament, connects to vas deferens

Function: allows sperm storage & maturation. Sperm travels from head → body → tail → vas deferens

What are the 3 main ligaments for the testis?

• Proper ligament of testis

• Ligament of tail of epididymis

• Scrotal ligament

What is the spermatic cord?

The structures running to & from testis. Contains nerves, vas deferens, & blood and lymph vessels

What makes up the spermatic cord?

• Vas deferens

• Deferent artery & vein

• Testicular artery & vein

• Lymphatic vessels

• Testicular nerves

• Cremaster muscle (technically sits outside but is still associated with it)

What is the function of the vas deferens?

Carries sperm to prostatic urethra

• Starts at tail of epididymis

What is the function of the testicular artery?

Supplies oxygenated blood to the testes & involved in counter current heat exchange system w/ veins

What is the function of the testicular vein?

Draining blood from testes, reduces temp of blood entering the testis to help maintain optimal testis temp

What is the function of the cremaster muscle?

A thermoregulatory mechanism to cool or warm the testis

• Contraction allows retraction of testis to increase testicular heat

• Relaxation moves testis away from body to help cool

What is the gubernaculum?

Is what attaches to the testis to draw them down during puberty - holds testis in place once dropped and prevents twisting of testis

• Has 3 layers: Pars propria, Pars vaginalis, Pars infravaginalis

What is cryptorchidism?

When one or both of the testes do not decent into scrotal sac (in carnivores)

• Decent should descend by 2 months of age

What are the internal reproductive organs?

• Urethra

• Accessory glands

  • ampullary glands

  • prostate

  • bulbourethral glands

What are the 2 regions of the urethra?

• Pelvic/Internal urethra

• Penile/External urethra

What is the function of the ampullary glands?

Produce a small proportion of ejaculate & helps in expulsion of fluid

• Structure not present in the cat

What are the parts of the prostate and what is its function?

Parts:

• Large compact part around proximal urethra (is bi-lobed)

• Vestigial disseminated part within urethral mucosa

Function: produces bulk of seminal fluid (exocrine gland)