ANSC 431 EXAM 4 QUESTIONS AND
ANSWERS
why is lactation tied to reproduction? - Answer-many of the endocrine events that drive
lactation after parturition are initiated during gestation by hormones secreted by the
placenta
-synchronicity between initiation of lactation and the point parturition occurs
mammogenesis - Answer-development of the mammary gland
-starts in fetal development
what tissues does the mammary gland have? - Answer-stomal, ductal and secretory
mammary gland development - Answer-1. mammary ridges
2. primary mammary buds
3. secondary buds
4. canalization
mammary ridges - Answer-thickened epidermal tissue that gives rise to the mammary
gland
-positioning is species dependent
-tissue begins to invade and penetrate the dermis
primary mammary buds - Answer-epidermal tissue invades into dermis to
secondary mammary buds - Answer-protrusions form away from primary bud and
branch further into dermis
canalization - Answer-secondary buds branch and lengthen and develop into canals for
future duct system
-myoepithelial cells surround terminal ends
-allows passage of milk
what are the 2 types of mammary gland positioning and species that go with them? -
Answer-thoracic = primates
inguinal = cow, ewe, goat, mare, sow, dog, cat (domestic species)
-changes how many ducts/canals per teat
isometric growth - Answer-mammary growth between brith and puberty
-not noticeable
allometric growth - Answer-growth between puberty and pregnancy
-growth rate faster than body
, what happens to mammary growth during puberty? - Answer-duct and alveolar
framework is constructed in mammary gland
how does estrogen and progesterone influence mammogenesis? - Answer-estrogen=
duct size and number
progesterone= alveoli development
how can overfeeding cattle in the prebutal period affect mammary development? -
Answer--increase fat deposition in mammary gland
-decrease secretory tissue decrease future milk production
pregnancy mammogenesis - Answer-complete alveolar development (ducts are 90%
mammary tissue)
-occur in last 1/3 of pregnancy
-alveoli = milk producing units
lobes - Answer-bunches of alveoli at ends of the terminal ducts
-myoeptihelial cells contract to squeeze alveoli to push the milk down into the ducts for
ejection through the teat
what hormones in late gestation promote milk production? - Answer-prolactin, adrenal
hormones, and placental lactogen
hormones in milk - Answer--all steroid hormones in milk
-protein hormones have no neonatal affect physiologically (they are hydrolyzed into AA
and lose biologic activity)
how many active peptides are in milk proteins? - Answer-15 active peptides
-control blood pressure, prevent clots, active immune system
pressure atrophy - Answer-build up of pressure causes secretory cells to become less
functional
-prolactin, adrenal cortical hormones, and placental lactogen restimulate alveolar cells
colostrum - Answer-first milk which contains lots of immunoglobulins (2-3 days)
-passive immunologic protection
are immunoglobulins only in colostrum? - Answer-yes, they are not in milk produced
later in lactation
how does colostrum or regular milk differ in compostiton? - Answer-colostrum is higher
in total solids, total protein, casein, fat, and immunoglobulins
what are the consequences of decreased antibody transfer? - Answer-negative long
term health problems
-fetus is immuno-compromised
ANSWERS
why is lactation tied to reproduction? - Answer-many of the endocrine events that drive
lactation after parturition are initiated during gestation by hormones secreted by the
placenta
-synchronicity between initiation of lactation and the point parturition occurs
mammogenesis - Answer-development of the mammary gland
-starts in fetal development
what tissues does the mammary gland have? - Answer-stomal, ductal and secretory
mammary gland development - Answer-1. mammary ridges
2. primary mammary buds
3. secondary buds
4. canalization
mammary ridges - Answer-thickened epidermal tissue that gives rise to the mammary
gland
-positioning is species dependent
-tissue begins to invade and penetrate the dermis
primary mammary buds - Answer-epidermal tissue invades into dermis to
secondary mammary buds - Answer-protrusions form away from primary bud and
branch further into dermis
canalization - Answer-secondary buds branch and lengthen and develop into canals for
future duct system
-myoepithelial cells surround terminal ends
-allows passage of milk
what are the 2 types of mammary gland positioning and species that go with them? -
Answer-thoracic = primates
inguinal = cow, ewe, goat, mare, sow, dog, cat (domestic species)
-changes how many ducts/canals per teat
isometric growth - Answer-mammary growth between brith and puberty
-not noticeable
allometric growth - Answer-growth between puberty and pregnancy
-growth rate faster than body
, what happens to mammary growth during puberty? - Answer-duct and alveolar
framework is constructed in mammary gland
how does estrogen and progesterone influence mammogenesis? - Answer-estrogen=
duct size and number
progesterone= alveoli development
how can overfeeding cattle in the prebutal period affect mammary development? -
Answer--increase fat deposition in mammary gland
-decrease secretory tissue decrease future milk production
pregnancy mammogenesis - Answer-complete alveolar development (ducts are 90%
mammary tissue)
-occur in last 1/3 of pregnancy
-alveoli = milk producing units
lobes - Answer-bunches of alveoli at ends of the terminal ducts
-myoeptihelial cells contract to squeeze alveoli to push the milk down into the ducts for
ejection through the teat
what hormones in late gestation promote milk production? - Answer-prolactin, adrenal
hormones, and placental lactogen
hormones in milk - Answer--all steroid hormones in milk
-protein hormones have no neonatal affect physiologically (they are hydrolyzed into AA
and lose biologic activity)
how many active peptides are in milk proteins? - Answer-15 active peptides
-control blood pressure, prevent clots, active immune system
pressure atrophy - Answer-build up of pressure causes secretory cells to become less
functional
-prolactin, adrenal cortical hormones, and placental lactogen restimulate alveolar cells
colostrum - Answer-first milk which contains lots of immunoglobulins (2-3 days)
-passive immunologic protection
are immunoglobulins only in colostrum? - Answer-yes, they are not in milk produced
later in lactation
how does colostrum or regular milk differ in compostiton? - Answer-colostrum is higher
in total solids, total protein, casein, fat, and immunoglobulins
what are the consequences of decreased antibody transfer? - Answer-negative long
term health problems
-fetus is immuno-compromised
