1. Livestock Reproduction
Animal Science I
Livestock Reproduction

2. Reproductive Terms Parturition Gestation Estrus Castration
The process of giving birth
Gestation
The time an animal is pregnant
Estrus
The time a female animal is receptive to breeding
Castration
The process of removing a male animal’s testicles

3. Parturition The signs of approaching parturition can be observed.
Females begin to exhibit nesting behavior
They becomes restless and attempt to separate from the herd or flock.

4. 1st stage 2nd stage 3rd stage
Dilation of cervix and entry of fetus into the cervix
2nd stage
Completes the birth of an animal through strong uterine contractions
3rd stage
Expulsion of afterbirth (placenta) from the uterus.
If the placenta is retained in can interfere with future reproduction.

5. Gestation Length varies from 174 days for a sow to 337 days for a mare
The new animal is known as an embryo while the organs are forming.
After differentiation and until birth the young animal is a fetus.

6. Estrus Period of heat or estrus are triggered by the hormone estrogen.
Ovulation takes place during estrus for ewe, sow, mare and some companion animals.
The cat only ovulates after mating.
The number of eggs ovulated varies.
Cows and mares typically ovulates one egg.
Dogs, horses, and cats may ovulates several eggs (15 or more)

7. Castration Makes the male animals easier to handle Methods: Elastrator
Stretches a specially made rubber band over the scrotum which will cut off circulation.
Knife or scalpel
With this method bleeding must be stopped and flies controlled
Budizzo clamps
No Bleeding
Clamp crushes and severs the cords and blood vessels going to the testicles.

9. Reproductive System of a Cow

10. Parts of the Female Reproductive System
Ovaries
Two organs located near the end of the reproductive tract inside the body cavity
Produce ova called eggs

11. Oviducts
Two tubes that carry the eggs from the ovaries to the uterus and are also called the fallopian tubes
Carries eggs from ovaries to uterus

12. Oviduct of a Hen Infundidbulum Magnum Isthmus Uterus
Vagina with egg inside

13. Infundibulum Funnel shaped end of each oviduct near the ovary
Picks up eggs at ovulation and directs eggs into oviduct

14. Uterus
Also called the womb
Place where the fetus grows

16. Cervix Neck of uterus Separates the uterus from the vagina
Serves as a passageway from sperm to travel from the vagina to the uterus and also seals the uterus during pregnancy

17. Vagina Connects the vulva to the cervix
Receives the male penis and sperm at breeding
Serves as a passageway fro urine to be expelled

18. Vulva
External opening to female reproductive and urinary systems

20. Livestock and Poultry Male Reproductive Parts

21. Scrotum Sheath Saclike part outside livestock
Holds and protects the testicles
Sheath
Protects the penis from injury

22. Testes or testicles
Two oval structures inside the scrotum in livestock and inside the body cavity of poultry on each side of the backbone
Produce sperm and male sex hormones

24. Epididymis Long coiled tube connected to each testicle
Stores sperm while they mature

25. Vas deferens Seminal vesicles Prostrate gland Cowper’s gland
Tube that connect the epididymis to urethra
Seminal vesicles
Open to urethra
Prostrate gland
Near the urethra and bladder
Cowper’s gland
Near urethra

26. Penis Covered by the sheath
Part that penetrates the female at breeding
Deposits semen in female livestock
Papilla serve this function in poultry

27. Accessory male reproductive glands
Produce fluids to protect and carry the sperm
Cowper’s gland
Prostrate gland
Seminal vesicles

29. Testicles are removed by castration to keep males from breeding

31. Papilla is the organ in male poultry’s cloaca wall that puts the sperm in the hen’s reproductive tract.

32. Poultry Reproductive System
The major difference between livestock and poultry reproductive systems is that the embryo of livestock develops inside the female’s body and the poultry embryo develops outside the body.

35. Chickens (domestic birds) have only the left ovary and oviduct functional at maturity.
This is what produces the eggs
The right ovary and oviduct do not function

36. The ovary produces the ova (eggs) and hormones

37. In poultry eggs the yolk is the ovum.

38. The poultry oviduct has five parts
Vagina
Uterus
Isthmus
Magnum
Infundidbulum

40. The vent is the outside opening to the poultry reproductive tract.

41. The uterus and vagina are part of the egg production and egg laying process.

44. Functions of Poultry Reproductive System
Ovary
Produces ova or yolks and hormones
Infundidbulum
The place where fertilization takes place
Magnum
Secretes the thick egg white or albumen
Isthmus
Adds the two shell membrane

45. Uterus
Secretes the thin white, the shell, and the shell pigment
Vagina
Holds the egg until it is laid
Oviduct
Serves several functions because it is made up of several parts
Infundidbulum
Magnum
Isthmus

46. Incubation time for chickens is 21 days
Cloaca
Egg passes through
Semen is deposited here during breeding
Vent
Place where eggs pass out of the hen’s body
The outside opening
Egg
Function is reproduction but is eaten as food by humans and wild animals
Incubation time for chickens is 21 days
Incubation time for ducks and turkeys is 28 days

47. Types of Breeding Systems
Purebred Breeding
Mating a registered purebred male and female of the same breed
Angus X Angus

49. Crossbreeding Mating a male and female of different breeds
Angus X Hereford= Crossbred Calf
Crossbred X Purebred= Crossbred
Crossbred X Crossbred= Crossbred

51. Inbreeding Mating closely related animals Brother X Sister
Son X Mother
Father X Daughter

53. Linebreeding Breeding more distant relatives than inbreeding
Can be traced back to one common ancestor such as a grandparent
Cousin X Cousin

55. Grading up
Mating a purebred male (sire) to grade or unregistered or crossbred female (dam) to improve the herd
Yorkshire boar X Yorkshire/Hampshire sow

56. Hybrid vigor
The superior traits that come from crossbreeding causing the offspring to have traits better than either parent