1. Male Reproductive System
Veterinary anatomy

2. Male Reproductive System
The male reproductive system consists of the
Scrotum
Testes
Spermatic cord
Excurrent duct system
Epididymis
Ductus deference
Urethra
Accessory sex glands
Penis

5. Scrotum Functions Thermoregulation Sweat glands Thermosensetive nerves
Protection and support of testis

6. The scrotum is a two lobed sack
The scrotum is a two lobed sack. It protects and supports the testes and is required for proper temperature regulation.
The scrotum consists of four major layer. They are:
1) the skin.
2) the tunica dartos
Smooth muscle
Elevate testes for a sustained period of time in response to temperature or stress
3) the scrotal fascia
4) parietal tunica vaginalis
- The scrotal skin is heavily populated with sweat glands. These sweat glands are required for maintenance of proper testicular temperature. Sweating allows the scrotum to be cooled by evaporative heat transfer.

7. Scrotum Descent of testes into scrotum Timing:
Sheep / cattle = midgestation
Humans / horses = just before or after
birth

9. Testes Functions Produce male germ cells (spermatozoa)
Produce testosterone, inhibin and estrogen

10. Testes Structure: Testicular capsule Parenchyma Mediastinum
Rete tubules (rete testis)
Efferent ductules

12. Testes - Structure 1- Testicular capsule 1)Tunica vaginalis Visceral
Parietal
2) Tunica albuginea

15. Testis

16. Testes - Structure 2- Parenchyma A- Tubular compartment
Seminiferous tubules
B- Interstitial compartment
Leydig cells
Capillaries
Lymphatic vessels
Connective tissue

17. Testes - Structure 3- Mediastinum
Central connective tissue core that houses rete tubules
4- Rete tubules (rete testis)
Tiny channels thru which spermatozoa transported out of testis

18. Testes - Structure 5. Vasa efferentia (efferent ductules)
a. Collect sperm from rete testis
b. Carry sperm out of testis proper

22. Testes Seminiferous tubules Site of sperm production
Consists of 2 cell types:
Germ cells (eventual sperm cells)
Sertoli or nurse cells

23. Testes Sertoli cells Surround developing germ cells
Provide structural & metabolic support to spermatogenic cells
Produces:
Androgen binding protein (ABP)
Inhibin
Sulfated glycoprotein

25. Testes Blood-testis Barriers a. Cells surrounding seminiferous tubules
b. Prevent autoimmune reaction from destroying developing germ cells

26. Testes Leydig cells Located between seminiferous tubules
Produce androgens (testosterone)

27. Epididymis
Three parts
Head (caput)
Body (corpus)
Tail (cauda)

31. Epididymis - Functions
Sperm
Transport
Maturation
Motility
Concentration
Storage
Gains ability of fertilization

32. Vas Deferens Ductus deferens or deferent duct Paired ducts Ampulla
Wide end of vas deferens
Function
Sperm transport from epididymis to pelvic urethra

34. Spermatic Cord
spermatic cord extends from the inguinal ring to it’s attachment on the dorsal pole of the testis. It suspends the testis in the scrotum.
The function of the spermatic cord is provides the pathway to and from the body for testicular vasculature, Lymphatic and nerves.

35. Spermatic Cord
The spermatic cord also houses the ductus deferent, cremaster muscle and specialized vascular network called the pampiniform plexus.
The pampiniform plexus is a vascular structure consisting of an intimately intertwined artery and vein and this structure is important for proper temperature control of the testis

36. Spermatic Cord - Functions
Suspends testis in scrotum
Pathway to blood vessels, lymphatics, & nerves
Thermoregulation mechanism
Pampiniform plexus
Cremaster muscle
Pulse pressure eliminator

37. Spermatic Cord

39. Accessory Sex Glands Vesicular glands (seminal vesicles)
Prostate gland
Bulbourethral glands (Cowper’s gland)
Ampulla of ductus deference

41. Vesicular Glands Paired glands
Located at junction of urethra & vas deferens
Rough structure
Contribute large amount of fluid
Fructose & sorbitol: energy sources
Phosphate & bicarbonate: buffers

42. Seminal vesicle Absent in camel, dog and cat.
Lobulated type in ox and pig
Vesicular type in horse.
Shape:
Pyramidal in pig
Elongated and lobulated in ox, sheep and goat
Elongated sac in horse

46. Prostate Gland
Located caudal to seminal vesicles and close proximity to pelvic urethra
Bilobed in bull
Diffuse in ram
Surrounds urethra in dogs & humans
Function = cleanse & lubricate and secretes just prior during ejaculation
Only accessory gland in dog

47. Prostate Gland
The prostate gland of the dog is spherical, smooth and divided into right and left lobes which completely surrounded the urethra.
In the cat the prostate gland has an uneven surface and covers the urethra dorsally and laterally only.

50. Bulbourethral Glands Paired glands Buried under bulbospongiosus muscle
Function:
Cleanse urethra prior to ejaculation
Produce gel fraction
Adds considerable volume

52. Colliculus Seminalis Region of urethra where sperm mixes with
seminal vesicle secretions
Mixing incomplete in stallion
Sperm-free fraction & Sperm-rich fraction

54. Comparative of accessory sex gland
Ampulla
Bulbourethral
Int. prostate
Ext. prostate
Seminal vesicle
Animals + -
Horse Ox
Sheep&goat
Camel
Dog
Cat
Pig

55. Penis
Male copulatory organ
Consists of
Base
Shaft
Glans penis

56. Penis
Cavernous bodies:
Corpus spongiosum
Corpus cavernosum

58. Penis Sigmoid flexure Ram, buck, bull
Allows penis to be retracted inside body until erection occurs

61. Penis Retractor penis muscle Pair of smooth muscle
Dorsally attached to tail vertebrae
Holds penis inside sheath
Glans
Distal end of penis, contains sensory nerves
Sheath
Covers penis

64. Penis Two Types 1. Fibroelastic Bull, buck, ram, dog 2. Vasomuscular
Stallion, human