x exam 2 urinary system development II Flashcards
Urinary system intermediate mesoderm
kidneys and ureters
urinary system primitive hindgut
urinary bladder and urethra
what are the 3 series of kidneys
pronephros
mesonephros
metanephros
what become the definite kidney
metanephros
nephric tubules, each more ____ than predecessor
complex and efficient
pronephros arises from
cranial urogenital ridge (cervical region of embryo)
pronephric tubules
cluster of cells in a tubular arrangement; does not connect to pronephric duct when functional (lower vertebrates, sheep) they connect
pronephric duct from
distal end of pronephric tubules; grows caudally along dorsolateral body wall, lateral to urogenital ridge to cloaca
mesonephros
urogenital ridge
genital (gonadal) ridge
ventromedially located
urinary ridge
dorsolaterally located
pronephric duct induces urinary ridge to form
mesonephric tubules (thoracolumbar region of embryo)
arteries from dorsal aorta
tufts of capillaries= glomeruli
mesonephric tubule epithelium becomes
bowmans capsule
establishes functional ____
filtration unit (renal corpuscle)
when mesonephric tubules connect to the pronephric duct, the pronephric duct becomes
mesonephric duct
when does the mesonephros become the primary functional kidney of the embryo and fetus
2nd tirmiester of precocious speceis
3rd tirmester of non-precocious species
when does pronephros degenerate
once mesonephros established and functional
metanephros forms
2 primordia (metanephric diverticulum and metanephric mesoderm)
metanephric diverticulum
ureteric bud (outgrowth of mesonephric tubule)
metanephric mesoderm
metanephric blastema (mesoderm of urinary ridge in sacral region)
metanephric diverticulum grows toward
metanephric blastema
metanephric mesoderm forms
cap around ureteric bud
metanephric diverticulum dilated ends
renal pelvis and collecting ducts
metanephric mesoderm vesicles in mesoderm
metanephric tubules to glomeruli and tubules of nephron
remainng metanephric duct becomes
ureter
metanephros of domestic animals are
multilobular in structure
final shape of kidney
varies
ureteric bud _____
divides and subdivides
dilated ends
calyces
collecting ducts surrounded by metanephric blastema
region of glomeruli (cortex)
region of collecting ducts (medulla)
multilobular bovine kidneys maintains
calyx arrangment
unilobular appearing kidneys
fusion of adjacent cortices, adjacent melludas and calyces also fuse with some species variation
location of kidneys initially
forms in sacral/pelvic region
ascends to
cranial lumbar region
primary
differential growth of lumbar musculoskeletal structures
migration of developing kidney structures
right kidney migrates further cranial thanleft
mesonephros contributes to
reproductive system development; reaminder degenerates
mesonephric duct enters
pelvic urogenital sinus
metanephric duct (ureteric bud) begins as
diverticulum of mesonphric duct near urogenital sinus
expansion of urogenital sinus
caudal most mesonephric duct incorporated into urinary bladder
initial metanephric duct incorporated into urinary bladder
mesonephric duct becomes ____ located
caudally
mesonphric openings at
urethra
mesonphric becomes
ductus deferens in male
degenerates in
female
metanephric duct remains mroe ___ located
cranially
metanephric openings at
neck of uirnary bladder; ureter
metanephros actively produces
urine
urine excreted to
amniotic cavity via urogenital orifice; allantoic cavity via urachus and allantoic stalk
fetal fluids within amnionic and allantoic cavities _____ as gesetation progresses
increase
amnionic fluid volume generally ______ mid-gestation
stabilizes
allantoic fluid volume _____ throughout
increases
volume and contents regulated
form allantoic cavity
forma amniotic cavity
allantoic cavity formed by
absorption where allantois attaches to chorion (placental capillares)
late gestation additionally (amniotic cavity)
amniotic cavity formed by
swallowing; absorbed GI tract; circulation (fetus); placental capillaries
fetal fluids lubricate ____
birth canal
when you rupture chorioallantois and amnion, you get
allantoic and amnionic fluid
chorionattached to uterus, not passed with
neonate
in horse, cat, dog, allantois surrrounds _____ of amnion
all of amnion; amnion floats freely, ruptures and passes out with fetus
in ruminants and pigs, allantois ____ amnion
partly surrounds; some amnion contacts chorion;
amnion not free, ruptures, passes out with placenta
hydrops
excessive fetal fluids
hydrops primarily affects
cattle
what is more common in hydrops
allantois (hydrallantois)
hydrallantois
10-40x normal volume
primairily due to pathology of placenta
hydramnion
up to 10x normal volume
usually obstruction/atresia of fetal foregut (esophageal or duodenum)
hydrops may cause
restricted fetal growth or death/abortion
delivery of hyrops offspring via
calving or c-secion
BOLO
twinning, hypovolemic shock, retained placenta
congenital fetal anasarca
walrus or water puppy
anasarca
generalized, severe subcutaneous edema (and other body tissues)
variety of causes of anasarca
affect ablity of kidneys to regulate fetal fluids
lungs in anasarca
distressed/failure
increased fluid volume within
fetus
renal agenesis
absence of kidneys (unilateral or bilateral)
renal agenesis caused by
failure of one or both ureteric buds
metanephric mass is not
induced to form tubules
oligohydramnios
reduced amnionic fluid in renal agenesis
bilateral
prenatal development ok, dies postnatally
mesonephros can get by on
fluid volume regulation
placenta takes care of
waste exchange prenatally
congenital urorectal fistula
common cloaca that perists
congenital urorectal caused by
failure of urorectal septum to divide anorectal canal and urogenital sinus
clinical concern of congenital urorectal fistula
fecal material in urogenital tract
ectopic ureters
ureters attached in abnormal location (urethra, vagina, vestible)
diverticulum
ureteric bud arises in wrong locale
if distal to sphincters,
urinary incontinence
ectopic kidneys
kidney in an abnormal location (unilateral or bilateral)
metenephric kindeys fail to
migrate/relocate
metenphric kidneys remain in
sacral region
ectopic kidney function
normal, incidental finding
horseshoe kidney
abnormal kidney shape (right and left metanehric masses fuse across midline)
typically ____ pole
caudal
often located in a more ____ postion
caudal (caudal mesenteric artery)
function of horseshoe kidney
normal
congenital cystic kidney disease
polycystic kidney disease inherited
congenital cystic kidney disease common in
persian cats (reported in scottish folds, himalayans)
anormality is congential
fialure of tubules to connect with colelcting ducts
formation of cysts wtihin nephrons
kidneys become progressively more ____ over time
cystic
as cysts grow, displaces/destorys
normal kidney tissue
results in
renal insufficiency or failure
symptoms appear
3 to 10 years of age