Male Reproductive Tract

1. Male Reproductive Tract Information comes from IMS 8405

2. Objectives • Students will discover parts of all male livestock animals • Students will learn vocabulary relating to male reproduction • Students will learn the functions of all the parts of male livestock

3. Introduction • Animal repro is a complex but interesting topic • It requires a basic knowledge of reproductive anatomy and physiology?. • Reproduction is the process of producing offspring for the purpose of continuing a species

4. The Process (summed up for now) • 1. Begins with copulation • 2. Sperm meets the ovum and forms an embryo • 3. Embryo attaches in uterus and stays until parturition

5. Bovine Male Reproductive Tract

6. Equine Male Reproductive Tract

7. Porcine Male Reproductive Tract

8. 4 Major Functions • 1. Production, storage, deposition of sperm • 2. Production of certain male hormones • 3. Excrete urine from the bladder • 4. Serves as passageway

9. Testes

10. Testicle Functions • 1. Produces the male sex hormone testosterone • Testosterone causes the development of secondary male characteristics and libido

11. Testicle Function • 2. Produce sperm • Below is bovine sperm

12. Types of Sperm

13. Sperm Anatomy To the right is a dissected sperm cell.

14. Semen and ejaculation characteristics of farm species Cattle Dairy  Beef  Sheep  Swine  Horses  Volume (ml) 6  4  1-2  225* - 400  60* - 100  Sperm concentration (billion/ml) 1.2  1.0  3.0  0.2  0.15  Total sperm (billion) 7  4  3  45  9  Motile Sperm % 70  65  75  60  70  Morphologically normal sperm % 80  80  90  60  70  pH 6.5-7.0  6.5-7.0  5.9-7.3  6.8-7.3  6.2-7.8 

15. Testicle Tumor

16. Crypt Orchid • Definitely a problem – a testicle does not make the trip down through the inguinal canal and becomes trapped with the body of the animal. Sometimes the testicle still produces sperm make the animal viable in reproduction. If the testicle does not make it, it looks like the one on the left.

17. Scrotum Functions • Houses testes and protect them • Helps regulates the temperature of the testes with help from the cremaster muscle

18. Scrotum • Testicular temperature is approximately five degrees below the body temperature because sperm must develop under conditions cooler than body temperature.

19. Epididymis • A long, greatly coiled tube connected to each testicle • Responsible for the maturation, storage, and transportation of sperm cells.

20. Deferent Duct • Known as the vas deferens • Originates from the epididymus and serves as a passageway for sperm to the urethra • Includes the spermatic cord, a protective fibrous sheath consisting of smooth muscles, blood vessels, and nerves.

21. Vas Deferens

22. Vas Deferens Cross Section

23. Seminal Vesicles • Paired accessory glands which secrete seminal fluid • It provides two functions as a protections and transportation medium for the sperm upon ejaculation

25. Glands of the Tract • 1. Prostate Gland • Secretes a thick, milky fluid that mixes with the seminal fluid and provides nutrition and substance to the ejaculate • 2. Cowper’s Gland • Just prior to ejaculation, it secretes a fluid similar to seminal fluid to cleanse and neutralize the urethra from urine residue which can kill sperm cells. • 3. Retractor Penis Muscle

27. Accessory Sex Glands • http://www.ansi.okstate.edu/course/3443/study/video/bulant3.mov

28. Pelvic Urethra • The urethra is the passageway or tube which extends from the bladder to the end of the penis • Serves as the transportation route for the semen and urine • Semen is sperm + added accessory fluids.

30. Penis

31. Penis • The organ that allows copulation • When the penis is in the relaxed state, the rear portion penis forms an S-Shaped curve called the Sigmoid Flexure in certain livestock species.

32. Sigmoid Flexure • http://www.ansi.okstate.edu/course/3443/study/video/bulerec.mov

33. Sigmoid Flexure • This curve allows for the retraction and protection of the front portion of the penis • The bull, ram, and boar are termed fibroelastic because they are composed of more connective tissue and depend on less blood for erections • The stallions penis differs in that it is termed vascular and forms no SF when relaxed.

34. Penis • The sheath is the external portion of the male reproductive tract which serves to protect the penis from injury and infection. • Prepuce is the excess skin around the head of the penis

35. Penis Fibropapilloma • Often, VD’s can cause major problems in herds!

36. Back to Sperm • The development of sperm is called spermatogenesis is a process of cell division and maturation that begins with STATIONARY cells called spermatogonium and ends with motile cells called spermatozoa. • The process takes place in the seminiferous tubules of the testes.

37. Sperm • Sperm cells carry one-half the chromosomes normally found in that species • BACK TO TESTOSTERONE > > > > > > > > >

38. Testosterone • Made in the interstitial cells • It is produced in a response to an interstitial cell stimulating hormone which is produced in the anterior pituitary gland in the brain and transported in the blood. • Testosterone is an androgen hormone • Secondary male traits from testosterone: • Coarse hair, horns that are long and large at base, a deep voice, and pronounced muscle development.

39. This is for the Birds!

40. The End Get it in your hard head by studying!