Histologia de sistema urinário de veterinária

Prévia do material em texto

http://cal.vet.upenn.edu/projects/histo/Laburinary.htm
http://www.vetmansoura.com/Histology/Urinary/Urinary1.htm
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http://www.biology-pages.info/V/VertebrateKidneys.html
URINOGENITAL 
SYSTEM
PRESENTED BY:FATIMA KHARBE
URINOGENITAL SYSTEM
o URINARY SYSTEM OF VERTEBRATES INCLUDE KIDNEYS AND THEIR 
DUCTS.
o REPRODUCTIVE SYSTEM INCLUDES MALE AND FEMALE GONADS 
AND THEIR DUCTS.
o THE 2 SYSTEMS ARE INTIMATELY RELATED MORPHOLOGICALLY IN 
VERTEBRATES HENCE THE TWO SYSTEM ARE AS DESCRIBED AS 
UROGENITAL OR URINOGENITAL SYSTEM 
BASIC STRUCTURE OF EMBRYONIC 
KIDNEY
Pair of compact organs lying on 
either side of dorsal aorta.
Each kidney is composed of large 
no of units called as
URINIFEROUS TUBULES OR 
NEPHRONS.
Kidney tubules arise in the embryo 
in a linear series from mesoderm.
Each uriniferous tubule is 
differentiated into 3 parts.
1.PERITONEAL FUNNEL
2.MALPIGHIAN BODY
3.TUBULE
Urinary System -
Kidneys
Kidneys are pair of compact 
organs lying on either
Side of dorsal aorta.
Evolution of kidney takes place 
as:
ARCHINEPHROS
PRONEPHROS
MESONEPHROS
METANEPHROS
ARCHINEPHROS
Excretory organ of ancestral vertebrates.
Also called as HOLONEPHROS 0r complete kidney 
as it runs throughout the entire length of coelom.
Composed of pair of archinephric ducts.
Each duct has a pair of tubules to a segment.
Each tubule is opened by a nephrostome in coelom.
Near each nephrostome there is an external 
glomerulus.
All tubules are drained into duct 
Which opens in cloaca.
Archinephros
• Larvae of caecilians and Hagfish 
have this type of excretory system.
•Tissue fluid discharge from 
glomerulus<<coelom<<
•Nephrostome<<tubules<<
•Archinepric ducts<<cloaca.
PRONEPHROS
• 1 Embryonic tubule to appear hence called as 
pronephros.
• Also called as head kidney.
• Composed of pronephric ducts.
• Consist of 3 to 15 tubules segmentally arranged,
• Each tubules open into coelom by nephrostome.
• Also projecting into coelom there is an external 
glomerulus.
• In some cases glomeruli unite to form glomus.
PRONEPHROS
• All tubules of pronephros open into the pronephric
duct.
• Which opens into cloaca..
• Pronephros is functional only in embryonic or larval 
stage,and it is soon replaced by mesonephros.
• Pronephros is retained throughout life in adult 
cyclostomes and teleost fishes.
• Filtrate of blood through 
glomerulus<<coelom<<nephr
ostome<<
• Tubule<<pronephric
duct<<cloaca.
MESONEPHROS
• Develops from middle part of 
intermediate mesoderm.
• Form soon after degradation of 
pronephros.
• Mesonephros is functionally 
better than pronephros
• bcoz mesonephric tubules are 
numerous in number.
• They develop internal glomeruli.
MESONEPHROS
• They are also termed as 
wolffian body.
• Mesonephros is functional only 
in embryos in amniotes.
• In sharks n caecilians tubules 
extend posteriorly
• Throughout coelom such 
kidney is called as 
OPISTHONEPHROS.
Mesonephros • Soon with the degradation of 
pronephros the pronephric duct forms 
the wolfian or mesonephric duct.
• In amniotes mesonephros is functional 
only in the embryos and replaced by 
metanephros in adults
• Nephrpstomes are generally lacking in 
embryonic amniotes.
METANEPHROS
• Arise posterior to the mesonephros.
• It’s the functional kidney of higher vertebrates or 
amniotes.
• it is formed from the posterior end of the nephrogenic
mesoderm.
• When all metanephric tubules develop all mesonephric
ducts disappear except those
• Associated with testis in male forming vasa efferentia.
• It shows greater multiplication and concentration of 
nephrons.
• It s functional unit is nephron.
METANEPHROS
Renal Cortex:
Renal corpuscle
Convoluted tubules
Renal Medulla:
Collecting ducts
Loop of Henle
Each Minor calyx drains a tree of 
collecting ducts
within a renal pyramid
Pyramids are separated by 
columns of cortical tissues
called renal columns
The Renal pyramids
Nephron • The tubules differentiates into the
• 1) Bowman’s capsule
• 2) Proximal convoluted tubule
• 3) Loop of Henle
• 4) Distal convoluted tubule
• The distal convuluted tubule fuses with the collecting duct 
Renal corpuscle = Bowman’s capsule/glomerulus. The 
nephron is
• the metanephric excretory unit.
• The origin of the Renal corpuscle and tubules is distinct from 
the
• collecting duct (Metanephric duct)
• Duct systems merge
• Renal duct – sequence of differentiation
• renal corpuscle 􀃆 proximal tubule 􀃆 distal tubule
• Loop of Henle elongates into the medulla
URINARY BLADDER
Urinary bladder
Most vertebrates have urinary bladder to store urine before it is 
discharged.
FISHES: enlargement of mesonephric ducts called
TUBAL BLADDER.
AMPHIBIANS: termed as CLOACAL BLADDER.
AMNIOTES: ATLONTOC BLADDER
Mammals lack cloaca hence the kidney ducts or ureter lead directly 
into the urinary bladder which opens into URETHRA
GENITAL SYSTEM
• Vertebrates exhibit sexual reproduction.
• Sexes are separate with exception of few hagfishes and few bony 
fishes.
• Male gonads…..Testes ….. produces sperms
• Female gonads …..Ovaries ….produces ova 
• Gonads originate as a pair of genital ridges.
• Generally 1 pair of gonad are present but some vertebrates have 
single gonad.
TESTES AND MALE 
GENITAL DUCTS.• TESTES: Seminiferous tubules: 
sperm factory 
• Produces sperm 
• Mature spermatozoa will move to 
rete testis
• Then to efferent 
dutules<<epididymis<<vas 
deferens<<urethra.
• Testes also act as an endocrine 
gland produces teststerone.
OVARIES
Ovaries are found in pairs except in 
some cyclostomes and teleosts.
Ovary shows layer of germinal 
epithelium showing ova in various 
stages of development.
Mature eggs are releasesd in the 
oviduct .
This process is termed as 
OVULATION.
In the absence of testosterone:
The mesonephric duct degenerates
The Mullerian duct develops uninhibited
Mullerian duct - cranial funnel-shaped opening to the
coelom forms the fimbriare of the infundibulum
The cranial Mullerian duct forms the uterine tubes
The caudal end of the Mullerian ducts fuse to form 
the
uterovaginal canal that later forms the uterus and
the superior vagina
Intromittant organs:
• useful when fertilization is internal; introduce 
sperm into female reproductive tract
• found in some fish, some birds, reptiles, & 
mammals
• cartilaginous fish - appendages of pelvic 
fins called claspers direct sperm into female 
reproductive tract
• snakes & lizards - have pair of 
HEMIPENES 
• turtles, crocodilians, a few birds, & 
mammals - exhibit an unpaired erectile 
penis
• penis - usually a thickening of floor of 
cloaca consisting of spongy erectile 
tissue (corpus spongiosum) with 
grooves to direct sperm & ending in a 
glans penis (sensory endings that 
reflexly stimulate ejaculation)
GOT BORE??