Reproduction

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Reproduction

• MOST ECONOMICALLY IMPORTANT TRAIT IN FARM ANIMAL
  PRODUCTION
• determines number of saleable animals
• determines number of replacement females
• initiates lactation
• determines number of eggs sold

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Reproduction

• reproductive efficiency
• animals born/100 breeding females
• pigs per litter lambs/ewe eggs/hen

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Reproduction terminology
See table 11-1, page 215
COW
HEIFER
EWE
EWE LAMB
SOW
GILT
FILLY
MARE
PULLET POULTCHICK
HEN
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Reproduction terminology
See table 11-1, page 215
BULL
STEER
WETHER
RAM
BOAR
BARROW
STALLION
GELDING
Rooster/cock/tom
CAPON
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Figure 114  Female reproductive tract. Source
(a) Bearden and Fuquay, 1997 (b) Texas AM
University. Used with permission.
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Cow reproductive tract see Figure 11-4a in text
University of Kentucky AgriPedia
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Sow reproductive tract
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Reproductive Organs

• Oviduct
• Transport egg sperm
• Site of fertilization
• Uterus
• Transport of spermatozoa from cervix to uterus
• Site of embryo attachment nourishment
• produces hormone prostaglandin
• lyses (kills) a corpus luteum restarts estrous
  cycle

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Reproductive Organs

• Cervix
• Passageway for sperm fetus
• Barrier between uterus vagina protects uterus
• Vagina
• Copulatory (sexual union) organ
• Semen deposition (all livestock species?)
• Birth canal

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Ovaries
Follicles contain eggs (oocyte/ova) -produce
estrogen, induces heat/estrus Corpus Luteum (CL)
forms from follicle -produce progesterone
maintains pregnancy
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Estradiol and Progesterone during the Estrous
Cycle
CL Progesterone
Ovulation
Ovulation
Hormone Concentration
5
10
15
Estrus
Estrus
Days Relative to Estrus
See Figure 11-2 page 217
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Estrous Cycle

• Estrus period of time when female is sexually
  receptive to male (aka. heat)
• Due to increased concentrations of estradiol
• Signals approaching ovulation
• Estrous cycle period of time from one estrus to
  the next

ESTRUS NOUN ESTROUSADJECTIVE
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Reproductive characteristics of female animals

See table 11-1, page 208
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Hormones of female reproduction

• Hormone Source Function
• estrogen follicle estrus mating behavior
• uterine growth, mucus
• progesterone corpus luteum maintain pregnancy
• prostaglandin uterus kills corpus luteum
• FSH pituitary follicle development
• LH pituitary ovulation
• formation of CL

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LH and FSH During the Estrous Cycle
LH
Progesterone
Hormone Concentration
FSH
5
10
15
Estrus
Estrus
Days Relative to Estrus
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The Estrous Cycle in Cattle
LH
2nd
1st
Progesterone
Wave
Wave
Hormone Concentration
Estradiol
FSH
5
10
15
Estrus
Estrus
Days Relative to Estrus