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  3 
45  9 
Motile   Sperm %
70 
65 
75 
60 
Morphologically normal sperm %
80 
90  pH        

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 2. Cowper’s 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

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

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