This assignment is all about urinary system of animals.
It covers overview of urinary system with perfect pictures of different animal's kidney.
General histology of each part of system and each part of nephron.
At last a brief overview of important congenital diseases with pics....
4. OVERVIEW OF URINARY SYSTEM
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Urinary system Consist of
1. 2 kidneys
2. 2 ureter
3. 1 urinary bladder and
4. 1 urethra
The functional unit of the kidney is
called the nephron.
About a million in each kidney
“The Urinary System is a group of organs in the body concerned with filtering
out excess fluid and other substances from the bloodstream.”
https://geoface.info/eafb/e557814b9dca/the-urinary-system-of-horses-
horse-owners-47698d
6. OVERVIEW OF URINARY SYSTEM
The kidneys of pigs and sheep are oval in shape while the kidneys of
cattle are each divided into approximately 20 lobules.
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7. FUNCTION OF THE URINARY SYSTEM
KIDNEY
1. Regulate blood volume and
composition
2. Regulate pH
3. Produce 2 hormones and
4. Excrete waste
URETERS-
1. Transport urine from kidney to urinary
bladder
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Sheep Kidney Dissection
8. FUNCTION OF THE URINARY SYSTEM
URINARY
BLADDER
• Store urine and expels
through urethra
URETHRA
• Dischargeurinefrom
the body
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Kidney of Equine(Left)
9. STRUCTURE OF KIDNEY
E a c h kidney is enclosedin a renal
capsule, which is surrounded by
adipose tissue.
Internally, the kidneys consist of a
1. Renal cortex
2. Renal medulla
3. Renal pyramids
4. Renal columns
5. Major calyces
6. Minor calyces and
7. Renal pelvis.
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12. Two Types of Nephrons
• Shorter
• Mostly in cortex of kidney
• Produce "standard“ urine
Cortical
nephrons (85%)
• Nephrons at border of cortex
and medulla
• Responsive to ADH
• Can concentrate urine
Juxtamedullary
Nephrons (15%)
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13. FUNCTION OF NEPHRON
Nephrons perform three basic tasks:
1. Glomerular filtration
2. Tubular reabsorption, and
3. Tubular secretion.
Blood cells and most plasma proteins remain in the blood because they are too
large to pass through the filtration membrane.
The pressure that causes filtration is the blood pressure in the glomerular
capillaries.
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16. URINARY BLADDER
The urinary bladder is posterior to the pubic
symphysis
The shape of urinary bladder depends on how
much urine is contain. when empty, it look like a
deflated balloon
Capacity varies in different species
Smaller in female because uterus occupies
the space superior to the urinary bladder
Toward the base of urinary bladder, the ureter
drains into the urinary bladder via the ureteral
opening.
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17. URETHRA
The terminal portion of the urinary bladder
to the exterior of the body.
In both male and female, the urethra is the
passageway for discharging urine from the
body.
The male urethra also serves as the duct
through which semen is ejaculated.
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19. Capsule
The surface of kidney is covered by a
fibrous capsule.
Capsule is mainly comprised of
1. collagen fibers, but also contain
2. Smooth muscles and
3. Blood vessels
Outer layer – fibroblasts and collagen
fibers
Inner layer – myofibroblasts
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22. Juxtaglomerular Apparatus
Following three things make up the
apparatus
1. Macula densa
2. Juxtaglomerular cells
3. extraglomerular mesangial cells
It maintains necessary Blood
Pressure in kidney for glomerular
filtration.
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https://www.memorangapp.com/flashcards/67534/Kidney+Histology+Wee
k+9/
23. Bowman’s capsule
“It is a cup-like sack at the beginning of the tubular
component of a nephron in the mammalian kidney
that performs the first step in the filtration of blood
to form urine.”
Bowman’s Capsule has 2 layers:
1. Visceral Layer-Inner
Contains podocytes
2. Parietal Layer-Contains parietal epithelial
cells.
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24. GLOMERULAR CAPILLARIES
Glomerular endothelium has numerous fenestrations.
1. Fenestrations – larger
2. more numerous
3. more irregular
Endothelial cells in glomerular capillaries has large number of aquaporin-
1 water channels that allows fast movement of water through epithelium.
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25. Proximal convoluted tubule
Longer and are more numerous in cortex.
Have small and uneven lumen.
Contains single layer of cuboidal cells with
eosinophilic granular cytoplasm.
Cells have microvilli on their luminal surface.
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26. Distal convoluted tubule
Shorter in length, therefore are few in
number in cortex.
Have larger lumen.
Lined by small, cuboidal cells.
Cytoplasm stains less intensely.
Cells lack microvilli.
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28. Loop of Henle
1. Thin limbs – simple squamous epithelium.
Descends into medulla.
1. Thick limbs – cuboidal epithelium.
Ascends through medulla into cortex.
No brush border
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http://www.siumed.edu/~dking2/crr/RN015b.html
29. Collecting Tubule and Duct
Drain urine from nephron to renal pelvis.
Lie on medullary ray within cortex.
Progressively increase in diameter
towards medulla.
Simple epithelium - Squamous to
cuboidal.
Cell boundaries are seen
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34. congenital disease
A sate of abnormality that is present at or before
birth.
Congenital diseases of urinary system:
Mainly comprise of anatomical disease
May have serious functional consequences.
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36. Aplasia:
Absence of one or both kidneys.
1. Unilateral aplasia:
Absence of one kidney is called
Unilateral aplasia.
2. Bilateral aplasia:
Absence of both kidneys is called
bilateral aplasia
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http://slideplayer.com/slide/7464
570/
37. 37
X-ray of aplasia in cat one
kidney is missing
http://www.dvm360.com/tumkur-
narasimhan-dvm-ms-phd
38. Hypoplasia
The size of kidneys remain small as they
don’t grow properly due to defect in
recessive autosomal gene.
Usually associated with hyperplasia of
opposite kidney.
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pathologia.instagram
39. Hypoplasia
Etiology:
• May due to due to problem in sensitive
stage of metanephrogenesis.
Diagnosis:
• X-ray
• CT-scan
• Ultrasound
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http://radiopaedia.org/images/1391
705
40. Cyst in Kidney
Single or multiple cysts in
pig and dog kidney are
reported.
Presence of multiple cysts
is termed as congenital
polycystic kidney.
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www.epainassist.com/abdomina
l-pain/kidney/renal-cysts
41. Cyst in kidney
1. Type-I cysts are formed due to dilation
and hyperplasia of collecting tubules.
2. Type-II polycystic kidney is formed. Cysts
are thick walled with dense connective
tissue.
may involve one or both kidneys.
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https://library.med.utah.edu/
WebPath/RENAHTML/REN
AL124.htm
42. Cyst in kidney
3. Type-Ill cysts:
cysts in kidneys develop from tubules or Bowmen's capsule
with part of glomeruli in cyst.
• This condition is bilateral and causes considerable enlargement of kidney.
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43. Other diseases
• The patient's kidneys fuse together to form a
horseshoe-shape.Horseshoe kidney
• A condition where the ureter rather than
terminating at the correct position in urinary
bladder, terminates at other site
Ectopic Ureter
• Bladder duplication, dysplasia, hypoplasia,
agenesis, and exstrophy (congenital eversion)are
seen.
Miscellaneous
Bladder Anomalies
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47. Reference
Wheater’s functional histology
Textbook by Barbara Young, Geraldine O'Dowd, H. Burkitt, James Lowe, John W. Heath, Paul Wheater, and Phillip Woodford
Illustrate veterinary pathology Prof. R.S. Chauhan MVSc., PhD.
Merck veterinary manual By Scott D. Fitzgerald, DVM, PhD, DACVP, DACPV
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The renal column is a medullary extension of the renal cortex in between the renal pyramids. It allows the cortex to be better anchored.
The renal pelvis or pelvis of the kidney is the basin-like or funnel-like dilated proximal part of the ureter in the kidney.
The renal cortex is the outer portion of the kidney between the renal capsule and the renal medulla.
The renal medulla is the innermost part of the kidney. The renal medulla is split up into a number of sections, known as the renal pyramids.
The pyramids consist mainly of tubules that transport urine from the cortical, or outer, part of the kidney, where urine is produced, to the calyces, or cup-shaped cavities in which urine collects before it passes through the ureter to the bladder. The point of each pyramid, called the papilla, projects into a calyx.
The minor calyces surround the apex of the renal pyramids. Urine formed in the kidney passes through a renal papilla at the apex into the minor calyx; two or three minor calyces converge to form a major calyx, through which urine passes before continuing through the renal pelvis into the ureter
Renal corpuscle, also called malpighian body, filtration unit of vertebrate nephrons, functional units of the kidney. It consists of a knot of capillaries (glomerulus) surrounded by a double-walled capsule (Bowman's capsule) that opens into a tubule. It consists of a glomerulus - a tuft of capillaries composed of endothelial cells, and a glomerular capsule known as Bowman's capsule
The renal tubule is the portion of the nephron containing the tubular fluid filtered through the glomerulus.[4] After passing through the renal tubule, the filtrate continues to the collecting duct system.
Metanephrongenetic blatema is a embryological structure that is converted to the kidney.
Cyst :a thin-walled hollow cavity containing a liquid secretion
occurs when the skin over the lower abdominal wall does not form properly. The bladder is exposed on the outside of the abdomen.
