Animal Reproduction Extension beyond the Textbook Original Power Point Created by Casey Osksa Modified by Georgia Agricultural Education Curriculum Office June 2002

Conditions for Fertilization n Anatomy of Male & Female must be compatible n Female must be in Heat n Egg must be mature

What is the function of the Male? n produce large numbers of live sex cells (spermatozoa) n contribute 1/2 chromosomes

What are the Male Reproductive Organs? n Testicles - produce spermatozoa & male hormone Testosterone n Scrotom - sack which carries testicles –functions as a heat regulator n Monorchid - one fertile testicle n Cryptorchid - both testes remain in body cavity (sterile) n Castration - removal of testicles –lack sex drive –gain weight quicker

What are the Male Reproductive Organs? n Epididymis - tube connects to testes n storage of spermatozoa (200 billion at a time) n spermatozoa mature as they migrate through n Vas Deferens - tube connects to epididymus –if removed, can't reproduce = vasectomy

What are the Male Reproductive Organs? n Urethra - begins at bladder and continues through penis n Sigmoid Flexure - "S" shape in urethra allows for extension of penis outside of body for reproduction

Accessory Sex Glands n prostate n two seminal vesicles n two cowpers glands

What is the function of the Accessory Sex Glands? n provide medium for transporting sperm n adds volume n provides nutrients n cleans & flushes urinary tract

Reproduction in Males n After sexual maturity, sperm production is continuous n Testosterone is responsible for: –growth, development & activity of accessory glands –survival of spermatozoa –secondary sex characteristics:male voice, sex drive

Reproduction in Males n Semen - collective term for all fluid ejaculated n sperm and fluid from accessory glands

Artificial Insemination

What is the function of the female? n contribute 1/2 chromosomes n care for young in uterus and after birth until weaning

What are the Female Reproductive Organs? n Vulva - exterior portion of reproductive tract n provides visual signs of heat n Vagina - between vulva & cervix –Cows & Ewes: semen is deposited here –Mares & Sows: semen is deposited in the cervix

What are the Female Reproductive Organs? n Cervix - "Mouth of the womb" n opening into uterus n at birth cervix stretches to allowbaby to pass (most painful part) n during pregnancy cervix becomes blocked with a mucous plug to prevent infection

What are the Female Reproductive Organs? n Uterine Horns - two branches of uterus n Fallopian Tube - uterine horn becomes a small tube –lined with cilia which aid in egg migration

Ovaries n located at end of fallopian tubes n possesses large number of eggs in all stages of development n this is all the eggs she will ever have, unlike the male n very few eggs reach maturity n if not fertilized, the egg is reabsorbed by the body

Reproduction in Females n Farm animals reach sexual maturity at 4 months (sow) to 24 months (mare), then ¶ Female comes in heat (estrus) · Egg released by ovary ¸ Egg travels down tube until fertilized by sperm n Estrogen - female hormone which regulates estrus

What does "in heat" mean? n Heat is the time when a female is receptive to the male and will allow breeding to take place n Heat is actually divided into 4 phases of the cycle.

Estrous Cycle: ¶ Proestrus: ovary is about to release an egg · Estrus: female receptivity ¸ Metestrus: uterus prepares for pregnancy –fertilized egg attaches to uterus ¹ Diestrus: longest period of cycle –inactive n Estrous Cycles stop after conception, and begin soon after Parturition (birth)

Females also show external signs of "Heat" n aggressive behavior n swelling and/or color change of vulva

Gestation Period for Animals AnimalLength of gestation Human266 to 274 days Rabbit31 days Cattle284 days Mouse/Rat21 days Pig114 days Dog61 to 74 days Horse366 days

n Beef Terms n A Mature Male is called a: Bull Bull n A Mature Female is called a: Cow Cow n The act of Giving Birth is called: Calving Calving n Gestation = 283 days 283 days n A Castrated Male is called a: Steer Steer n An Immature Female is called a: Heifer Heifer

n What do you call a mature male hog? Boar Boar n What do you call a mature female hog? Sow Sow n What do you call the act of giving birth? Farrowing Farrowing n What do you call a castrated male hog? Barrow Barrow n What do you call an young female hog? Gilt Gilt n What is the gestation for hogs? 114 days or 3 months, 3 weeks, & 3 days 114 days or 3 months, 3 weeks, & 3 days

n Poultry Terms n What do you call a mature male? Rooster Rooster n What do you call a mature female? Hen Hen n What do you call a young female? Pullet Pullet n What do you call a castrated male? Capon Capon n Chickens Hatch n What is the incubation period? 21 days 21 days

n What do you call a mature male horse? Stallion Stallion n What do you call a mature female horse? Mare Mare n What do you call a castrated male horse? Gelding Gelding n What do you call a young horse? foal or colt foal or colt

n What do you call an immature female horse? Filly Filly n What do you call the act of giving birth for horses? Foaling Foaling n What is the gestation for a horse? 330 days 330 days