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Unformatted text preview: mass occurs. Pregnancy - 5 months
Pregnancy High levels of progesterone cause the lobules to
grow big enough so that they can make milk
The lobules crowd out the fat Mouse Mammary Development is Similar to Humans Mice can be used as a model for breast development Developmental Blocks of P and Prolactin (Prl)
Receptor) Hormonal Regulation of Lactation
Also, at least five other hormones are
needed for normal development and milk
(1) Growth hormone or somatotropin
(2) ACTH (adrenocorticotropin hormone)
(3) TSH (thyroid stimulating hormone)
(5) Thyroxine Hormonal
Lactation Ho rm o na l R e g ula tio n o f Milk Ho
R e le a s e (e) Milk release or let‑down Dependent on a “suckling reflex” under
neurohormonal control Suckling stimulates a nerve reflex within
the nerve cells of the teat . Ho rm o na l R e g ula tio n
Posterior Pituitary (brain):
Releases o xyto c in into blood Causes contraction of the m yo e p ith e lia l c e lls lining the alveoli and ducts Results in m ilk re le a s e o r le t‑d o wn This suckling reflex can be conditioned for ex. baby crying in humans. Mini review
What happens during Pro, Estrus, Metestrus,
Parts of female repro tract.
Ovary, infundibulum, oviduct, uterus, cervix,
Parts of the male reproductive tract
Testes, scrotum, epididymis, vas deferens,
urethra, sex glands, penis A.I. – advantages Effects of males on reproduction Genetic improvement, many offspring, no
STDs, no injuries Functions of placenta respiration, nutrition, excretion, hormone
production Gestation, Parturition Oxytocin...
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This note was uploaded on 10/21/2013 for the course ANIMAL SCI 101 taught by Professor Dr.sharma during the Fall '12 term at Rutgers.
- Fall '12