extra extra extra Flashcards

1
Q

definition of ascites

A

accumulation of fluid within abdominal cavity

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2
Q

cause of ascites

A

portal hypertension and hypoproteinemia

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3
Q

who does ascites affect

A

rarely in pigs most in dogs

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4
Q

signs of ascites

A

lower distended abdomen
abomdinal pain
lethary
decreased appetites

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5
Q

mechanism of ascites

A

all pressure within the capillaries are sometimes imbalanced, this imbalance causes edema

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6
Q

definition of cirrhossi

A

end stage liver failure accompanied with diffuse fibrosis and loss of regular structure

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7
Q

mechanism of cirrhosis

A
  1. Sinusoidal hypertension
    * Causes increased fluid leakage into Space of Disse with increased lymph formation
    * Makes it difficult for lymph to drain, so there’s overflow into peritoneal cavity = ascites
    * Transudate has high protein content and due to osmosis there’s fluid leakage = ascites
    * Also leads to portal hypertension causes increased capillary pressure in abdominal area and plasma leakage into peritoneal cavity = ascites
  2. Leads to hypoalbuminemia
    * Decreased albumin synthesis in liver, protein leakage from sinusoids = hypoalbuminemia
    * Decreasing blood osmotic pressure, plasma leaks into interstitium and abdominal cavity = ascites
  3. Causes plasma leakage from blood vessels
    * Causes noradrenaline release, causing vasoconstriction and increasing blood volume
    * RAAS is activated and ADH is excreted all causing edema and ascites
  4. Decreased liver blood flow
    * Portosystemic circulation is unable to metabolise noxious compounds
    * Peripheral vasodilation occurs causing edema and ascites
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8
Q

complications of cirrhosis

A

hepatorenal syndrome
HE
hepatic hydrothorax

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9
Q

definition of hepatorenal syndrome

A

precursor of kidney failure

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10
Q

mechanism of hepatorenal syndrome

A

Renal vasoconstriction due to peripheral vasodilation and intravascular volume depletion, causes decreased GFR, oliguria and uraemia

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11
Q

define HE

A

Decline in brain function that occurs as a result of severe liver disease. Liver cannot remove toxins from the blood, leading to build-up of toxins in blood stream, causing brain damage

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12
Q

mechanism of HE

A
  • Toxins (NH3) bypass liver and have toxic action on the brain
  • Ammonia is a waste product of AA metabolism and urea is formed by AA deamination and urea degradation
  • S.I digest protein, deaminates AA and produces ammonia, bacteria in large intestine degrade urea producing ammonia. Through portal circulation, ammonia enters urea cycle and is bio transformed into urea and kidney excretes. Can also be converted to glutamine in the liver
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13
Q

signs of HE

A

depression, tremor, stupor/coma

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14
Q

hepatic hydrothorax/pleural effusion definition

A

excessive accumulation of transudate in pleural cavity

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15
Q

mechanism of Hepatic hydrothorax

A

ascitic fluid effuses through diaphragmatic defects

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16
Q

signs of hepatic hydrothorax

A

animal can cough, dyspnoea, hypoxia or respiratory failure

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17
Q

what can hepatic hydrothorax result in?

A

hypoalbuminemia
portal hypertension
peripheral dilation
ascites and edema

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18
Q

fatty liver disease def

A

accumulation of triglycerides in the cytosol of the hepatocytes

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19
Q

mechanism of fatty liver

A
  1. Increased lipid influx to the liver from feed by chylomicrons
    a. Increased FA within hepatocytes, increased esterification, increased VLDL formation and triglyceride deposition in hepatocytes
  2. Increased lipid influx to the liver from adipose tissue
    a. Due to energy deficit, increased lipid mobilisation, increased FA oxidation, increased FA esterification and insufficient VLDL formation due to apolipoprotein deficit, triglycerides deposited
  3. Increased fatty acid and triglyceride synthesis from CHO
    a. Increase in FA and triglyceride synthesis, when increased carb content (due to high insulin concentration), increased FA esterification, triglyceride deposition
  4. Decreased VLDL formation and excretion
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20
Q

4 grades of fatty liver

A

1 - healthy liver and reversible
2 fatty infiltration
3 fatty degeneration and irreversible
4 cirrhosis

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21
Q

causes of fatty liver

A

energy deficit in ruminants (late pregnancy, early lactation), hormonal disorders (diabetes, hypothyroidism, hyperadrenocorticism), idiopathic fatty liver syndrome

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22
Q

biotransformation definition

A

conversion of endogenous and exogenous compounds into soluble compounds that are easily excreted

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23
Q

endotoxins

A

products of metabolism

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24
Q

exotoxins

A

drugs, potions from feed, products of microorganisms

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25
where does biotransformation occur?
in ER involving cytochrome P450 and UDP
26
detoxification
conversion to nontoxic metabolites
27
bioactivation
increased toxicity after biotransformation CCL4 causes oxidative damage to hepatocytes, halothane causes hepatitis
28
mechanism of biotransformation
stage 1 - no synthesis, increase polarity slightly by oxidation, reduction or hydrolysis stage 2 - synthesis of new compounds to increase polarity via conjugation, methylation and acetylation
29
disorder of biotransformation
causes decreased inactivation and excretion of endogenous metabolites, so they accumulate = liver cirrhosis
30
definition of jaundice
yellow pigmentation of skin and MM, clinical signs for hyperbilirubinemia
31
physiological mechanism of bilirubin
1. Prehepatic stage: spleen a. RBC enter spleen, phagocytosed by macrophages b. Globin is broken down into AA, which is reused for other protein synthesis c. Heme broken to biliverdin by hemoxidase d. Biliverdin broken down to bilirubin by biliverdin reductase e. Macrophage releases bilirubin, bilirubin binds to albumin and goes to portal circulation as unconjugated bilirubin 2. Hepatic stage: liver a. Bilirubin and albumin separate within sinusoid and bilirubin enters the hepatocyte b. Bilirubin reaches ER where it’s broken to glucuronic acid = conjugated bilirubin c. Conjugated bilirubin, exits hepatocyte by passing through biliary system into S.I 3. Post-hepatic stage: intestines and kidney a. Conjugated bilirubin transforms to urobilinogen and then stercobilinogen b. Stercobilinogen is excreted via faeces and is brown c. Urobilinogen goes through enterohepatic circulation
32
cause of haemolytic jaundice
babesia canis - directly invade and infected RBC causing lysis other microorganisms immune mediated haemolytic anamiea
33
mechanism of haemolytic jaundice
1. increased haemolysis > increased bilirubin production in spleen 2. increased unconjugated bilirubin into liver 3. Liver to intestine is increased conjugated bilirubin -> converted to stercobilin 4. increased absorption of urobilinogen 5. increased urobilin in urine
34
hepatocellular jaundice cause
decreased bilirubin uptake by hepatocytes, decreased bilirubin conjugation and impaired bilirubin excretion • Infectious hepatitis, toxic hepatitis, hepatic lipidosis, liver fibrosis and cirrhosis
35
mechanism of hepatocellular jaundice
1. decreased bilirubin uptake by hepatocytes and conjugation 2. Impaired bilirubin excretion into bile canaliculi 3. Urobilinogen decreased, stercobilin decreased and results in pale faeces 4. increased urobilin, dark urine and increasedbilirubin
36
obstructive jaundice cause
impaired bile flow by extrahepatic ducts (biliary obstruction). Intraluminal obstruction (gallstones, parasites, inflammation), extraluminal obstruction (tumours)
37
mechanism of obstructive jaundice
1. Conjugated bilirubin stays in liver and returns to systemic circulation 2. Urobilinogen and stercobilin decreased = pale, fatty stool 3. Conjugated bilirubin increased in blood, in kidney decreased in urobilin and increased bilirubin = greenish urine
38
definition of hypoventilation
* Alveolar spaces aren’t filled with an adequate amount of fresh air so oxygenation of the blood in the lung capillaries is disturbed  hypercapnia (increased CO2, hypoxemia and hypoxia)
39
compensatory mechanism of hypoventilation
1. Reflex tachypnoea and increased depth of breathing 2. Decreased affinity of Hb to oxygen 3. Stimulation of vasomotor centre leading to tachycardia and hypertension 4. Increased erythropoietin
40
hyperventilation
Causes compensatory metabolic acidosis, hypoxemia and hypoxia. There is stimulation of the respiratory centre during hyperthermia, encephalitis and meningitis
41
definition of asthma
periodic episodes of severe and reversible bronchial obstruction in hypersensitive or hyperresponsive airways
42
cause of asthma
hypoxia (decrease of air flow with increased need for air), hypoxemia (vasoconstriction of lung blood vessels leading to right heart overload)
43
seize and signs of asthma
acute seizure: bronchoconstriciton, inflammation, swelling and mucus secretion in the lumen signs: cough, severe dyspnoea, mucus expectoration, tachycardia, respiratory acidosis
44
extrinsic/intrinsic asthma
extrinsic = more common in young animals, partial/total obstruction of airways and severe hyoxia intrinsic = more common in adults, non-specific stimuli target on hyper responsive mucosa
45
status asthmaticus
severe asthma seizure, not responding to therapy
46
chronic obstructive bronchitis cause
hypersecretion, diffuse obstruction and chronic productive cough
47
chronic obstructive bronchitis caused
by inflammation as a result of prolonged inhalation of various irritant mucosal gland hypertrophy and hyperplasia fibrosis and induration of bronchial wall
48
signs of chronic obstructive bronchitis
progressive productive cough, sputum, weight loss, tachypnoea and cyanosis
49
lung emphysema definiton
destruction of alveolar walls and septa with big and permanently enlarged alveolar spaced
50
theory of lung emphysema
Mechanistic theory: * Bronchiolitis causes histamine release and swelling leading to luminal obstruction * Laboured inspiration and expiration occur * Alveolar walls and capillary networks distend * Causes capillary atrophy and redirection of circulation in healthy regions in the lung * Increased pressure in pulmonary artery leads to right heart hypertrophy (cor pulmonale) * Polycytemia as a compensatory mechanism occurs * No longer works due to increased blood viscosity and a weak heart Biochemical- enzymatic theory: * Alpha 1 antitrypsin in an atnielastase deficiency * Elastin function lost, so alveoli cannot retract
51
consequence of lung emphysema
decreased areas of gas exchange loss of capillary networ loss of elastic fibre pneumothorax, lung hypertension
52
restrictive respiratory system disease defintion
decreased lung movement and decrease of total lung capacity
53
pleural disease
pleuritis: wet, cause pain and atelectasis hydrothorax= increased hydrostatic pressure / decreased oncotic pressure pneumothorax = closed, open or ventile (can result in cardiac shock)
54
atelectasis definition
aeration failure and lung collapse - alveolar collapse disturbs lung circulation and can lead to necrosis, epithelial destruction and fibrosis of the lungs
55
types of atelectasis
obstructive = foreign body, inflammation, paraistes compressive = pneumothorax, hydrothoax post-op
56
neonatal respiratory distress syndrome
Occurs: in premature piglets and puppies Caused: insufficient amount of surfactant During exhalation, the residual volume is exhaled and lungs collapse
57
lobar pneumonia
localised on one or more lobule, in affected areas, no healthy tissue exists
58
stages of lobar pneumonia
Congestive stage: vascular congestion of alveolar walls and exudate accumulation in alveoli * Lowest blood oxygenation Hepatisation stage (consolidation): N, RBC and fibrin accumulation forming firm mass in lobuli * Red: due to hyperaemia * Grey: due to leukocytes and fibrin accumulation * Yellow: tissue becomes softer and wet
59
symptoms of lobar pneumonia
fever, hyperventilation, dehydration, dyspnoea tachypnoea and productive cough
60
symptoms of lobar pneumonia
fever, hyperventilation, dehydration, dyspnoea tachypnoea and productive cough
61
bronchopneumonia
* is characterised by small foci of inflammation which can merge * Usually on ventral parts and caused by bacteria * Spreads from bronchioles to alveoli * Exudate in alveoli prevents oxygen diffusion, bronchioloi are filled with mucus and alveoli with exudate * Alveolar walls become thick * Hypostatic pneumonia
62
aspiration pneumonia
Def: entrance of foreign bodies or fluids in trachea and lungs, causing obstruction, inflammation and swelling * Airways are obstructed and lungs cannot move correctly, which compromises gas exchange * Leads to possibility of infection and pulmonary abscesses * Can progress to non-cardiogenic lung edema
63
cystic fibrosis definition
genetic disease which causes abnormally thick mucus production in the mucus glands
64
cystic fibrosis others (what's more affected and causes)
* Lungs and pancreas mostly affected * More prone to infection Causes: airway obstruction, atelectasis and infection, cor pulmonale and respiratory distress
65
cardiogenic lung edema
* Is haemodynamic * Capillary pressure increases causing congestive heart failure and pressure increase in left atrium, occluding lung veins * The fluid that accumulates in interstitial spaces, is low in proteins and decrease oncotic pressure in interstitium * Pulmonary volumes and air circulation are decreased and respiratory work increased * Managed by diuretics and vein dilators
66
non cardiogenic lung edeam
* Is an Angio-mural edema * Occurs after the latent period, following acute lung injury or systemic conditions: shock, MOD or pancreatitis * Capillaries are damaged, which causes neutrophil aggregation and ROS production * Proteases are released in the lung tissue leads to inflammation * Damage to alveolar pneumocytes type II causes decreased surfactant production, leading to atelectasis, allows for penetration of plasma and erythrocytes into interstitial space and alveoli
67
signs of non-cariogenic lung edema
cough, dyspnoea, restlessness, rapid and shallow breathing, tachycardia, stridor, foamy sputum
68
lung hypertension
* Caused by lung diseases with vasoconstriction or structural changes in the blood vessels * Left heart failure causes secondary lung hypertension as it increases pressure in the veins of the lungs * Can also be a result of congenital heart malformations * Hypoxia occurs due to pulmonary artery vasoconstriction * Cor pulmonale is hypertrophy and dilation of the heart, as well as right heart failure. Causing acute cardiogenic shock or can be chronic with polycytemia and increased blood viscosity
69
hormonal regulation of renal function
RAAS aldosterone ADH ANP
70
RAAS
* Renin is released from juxtaglomerular cells as response to decreased BP * Renin converts angiotensinogen into angiotensin I * Angiotensin I then converted to angiotensin II * Angiotensin II stimulates vasoconstriction
71
aldosterone
* Released from adrenal cortex * Stimulates the Na/K ATPase in the distal tubule and collecting duct leading to Na+ and Cl-
72
ADH
* Produced and released from posterior pituitary gland * Water and sodium reabsorption in distal tubule and collecting ducts
73
ANP
* Secreted from cardiac atria in response to increased BP, which is caused by an increase in extravascular fluid * causes vasodilation of the afferent arteriole * decreases salt and water reabsorption in the distal tubule and collecting duct * decreases renin, aldosterone and ADH secretion
74
cause of pre renal disorders
Caused: decreased renal blood flow due to systemic circulatory disorders * reduced arterial blood pressure (severe hypovolemia, shock, heart failure) * venous pathology (thrombosis, increased venous pressure) * increased intraabdominal pressure (liver cirrhosis with ascites) All decrease the renal perfusion, which leads to: * deceased GFR, renal ischemia, decreased energy metabolism, disorders of tubular reabsorption and secretion and renal failure
75
1st stage of pre renal disorder
COMPENSATORY PHASE * maintain the normal kidney function (GFR, tubular functions) * afferent arteriole dilatation and efferent arteriole constriction in order to increase the glomerular filtration pressure and readily increase the GFR * there’s increased water and sodium reabsorption in response to angiotensin II, aldosterone and ADH * sympathetic nervous system causes systemic and renal vasoconstriction leading to increased volume and BP
76
2nd stage of pre renal dirosrder
* no more possibility of afferent arteriole dilation and efferent arteriole constriction * decrease in GFR * strong sympathetic and RAAS activation  renal vasoconstriction, additional decrease in GFR  oliguria * also leads to failure of the liver (hepatorenal syndrome) o liver cirrhosis, portal hypertension, ascites, edema, uraemia and azotaemia…
77
definition of glomerulonephritis
inflammation of the glomeruli
78
cause of glomerulonephritis
accumulation of microorganisms within glomeruli, antibody binding to basement membrane and deposition of antigen-antibody complexes within the glomeruli * upon immune complex deposition, inflammation develops. Immune complexes are deposited into the subendothelial, subepithelial or mesangial part of the basement membrane, causing leukocyte infiltration and mesangial cell proliferation causing inflammation
79
mechanism of glomerulonephritis
* deposition of immune complexes in the glomeruli, causes infiltration by immune cells and platelets * then release of cytokines, serotonin, histamine, proteases leading to inflammation and damage of glomerular filtration barrier  increased permeability and proteinuria * damage cells for platelet binding, activation of coagulation and fibrin deposition * fibrin decreases capillary lumen and the GFR * fibrin enters the bowman’s space and makes nodules that press on capillaries  decreasing GFR
80
decreased GFR from glomerulonephritis
* decreased area of glomerular filtration barrier * decreased glomerular blood flow and filtration pressure * oliguria * tubular compensatory mechanism: increased Na+ and water reabsorption  hypovolemia  hypertension  nephritic edema
81
increased glomerular membrane permeability. - glomerulonepritis
* proteinuria causes hypoalbuminemia and decreased osmotic pressure: o edema, decreased blood volume, decreased CO  heart failure, decreased renal blood flow  kidney failure  nephrotic syndrome * haematuria, lipiduria, pyuria
82
nephritic syndrome
* Immune complexes in glomerulus * Decreased glomerular filtration, oliguria, azotaemia , mild proteinuria, hypertension due to decreased GFR  edema
83
nephrotic syndrome
* Increased glomerular permeability, massive proteinuria  edema * Loss of antithrombin III  thrombin * Decreased cardiac output * Decreased renal blood flow
84
renal artery stenosis
* Occur due to progressive development throughout life, or in older animals due to atherosclerosis * Stenosis is the narrowing of a vessel, so when the renal artery is narrowed, there’s decreased renal perfusion * Renal artery stenosis can be compensated for by the autoregulation of GFR, but eventually kidneys will be exposed to chronic ischemia which decreases GFR * Then RAAS activation, ADH and sympatheticus  vasoconstriction  renovascular hypertension  fibrosis of tubules and glomeruli  chronic renal failure
85
thromboembolic renal disease
* Occur due to thrombi in arterial or venous blood stream * Renal artery thrombus comes from the heart  cause partial or total obstruction * Partial obstruction  reduced GFR and tubular reabsorption * Total obstruction  infarction of the parenchyma  irreversible necrosis * Renal vein thrombus comes from increased tendency to clot
86
definition of TI renal disease
impaired structure and function of tubules and the surrounding interstitium, 3 main diseases: TI nephritis, pyelonephritis and ATN
87
cause of TI renal disease
Primary cause: toxins, drugs, ischemia and infection Secondary cause: glomerulonephritis, vascular renal disease and urinary tract obstruction
88
mechanism of TI renal disease
Early stage (1): normal glomerular function * Tubular function is damaged  mild/moderate proteinuria * Reduced reabsorption of albumins and smaller proteins  polyuria * Reduced reabsorption of sodium with reduced secretion of H+  metabolic acidosis Late stage (2): secondary glomerular injury * Damaged tubular cells end obstructing the tubular lumen, leading to secondary glomerular damage * Increases proteinuria, free tubular cells, urine casts and haematuria and leukocytes in the urine
89
TI nephritis def
inflammatory process of renal tubules and intersititum
90
TI nephritis infectious/non infectious
Infectious: viral or bacterial septicaemia, where pathogens localise in the capillaries of the interstitium leading to inflammation. There’s subsequent degeneration of tubular cells and leakage into the interstitium  interstitial edema * Results in tubular function damage due to the edema Non-infectious: caused by drugs and toxins that directly cause degeneration and necrosis of tubular cells. Allows for fluid to leak into the interstitium  interstitial edema
91
def pyelonephritis
Def: inflammation of renal pelvis associated with ureter infection
92
cause of pyeloneprhtisi
ascending infection from the urinary tract via contaminated urine reflux into the renal pelvis * Expansion of infection to tubules and interstitium  tubulointerstitial nephritis * Pathogens: E.coli, klebsiella, staph and strep
93
acute/chronic pyelonephritis
Acute: occurs rapidly with systemic signs of infection, pain and stranguria with pollakiuria. Urine changes include leukocyte, bacteria and urine casts Chronic: severe disease with the destruction of renal parenchyma due to reduced tubular function. Kidneys cannot concentrate urine, reabsorb sodium or excrete H+ sufficiently anymore
94
def ATN
Def: degenerative disease of renal tubules without inflammation with acute degeneration and necrosis of tubular epithelium * Most common cause of acute renal failure
95
cause of ATN
nephroxotins (atb, analgesics, anaesthetics, heavy metals) ischema
96
mechanism of ATN
* RAAS activation and vasoconstriction leading to decrease in GFR and oliguria - because of damage, there’s tubular obstruction, increase in tubular pressure, decreasing gGFR > oliguria * Increase in intratubular pressure causes tubular back leak  interstitial edema * Tubular cell damage also leads to decrease sodium reabsorption  further RAAS activation and vasoconstriction, decreasing GFR even further
97
acute renal failure def
sudden loss of kidney functions
98
acute renal failure
* First, there’s a reduced Na+ reabsorption and K+ secretion * Causes: hyponatremia and hyperkalaemia in the body * Reduced H+ excretion, leading to metabolic acidosis * Decreased calcitriol leads to hypocalcaemia * Leads to reduced GFR, causing hyperphosphatemia, oliguria, anuria and azotaemia Prerenal: systemic circulatory disorders, low renal perfusion, ischemia Renal: acute glomerulonephritis, acute tubulointerstitial nephritis, nephrotoxic injury leading to ATN Postrenal: urinary tract obstruction
99
chronic renal failure def
progressive and irreversible nephron damage and loss of kidney function
100
stages of chronic renal filuare
Stage 1: * Reduced GFR to 30% * Other functions are preserved Stage 2: * Further decrease of GFR to 15% * Reduced excretion leading to azotaemia * Reduced urine concentration * Anaemia due to reduced erythropoietin * Hypertriglyceridemia due to reduced lipoprotein lipase activity Stage 3: * Severe anaemia * Severe arterial hypertension * Disorders of cardiovascular, digestive and nervous system Stage 4: * Significantly reduced GFR to <5% * Terminal uraemia leading to uremic syndrome
101
ureic syndrome def
clinical syndrome in 4th stage of chronic renal failure. Characterised by increased concentration of uremic toxins in the blood including urea, creatinine, guanidine, uric acid
102
disorders of ureic syndrome
Carb metabolism (hyperglycaemia), acid-base imbalance (reduced H+ excretion), anaemia and hypocalcaemia (decreased production of erythropoietin and calcitriol), gastrointestinal disorders (stomatitis), heart and respiratory disorders, atherosclerosis, skin disorders and disorders of CNS
103
insulin
* decreases blood glucose levels, enhances the entrance of glucose in cells, glucose phosphorylation, glycogen synthesis, lipogenesis and protein synthesis in muscles
104
glucagon
* increases blood glucose levels. Increases glycogenolysis, gluconeogenesis and lipolysis
105
catecholamine
* Increases blood glucose levels. Enhance glycogenolysis in the liver and muscles, as well as lipolysis and glucagon secretion. Adrenaline also stimulates adrenocorticotropic hormone secretion
106
GH
* Increases blood glucose. GH directly damages beta cells and insulin production. Also, inhibits glucose entrance and oxidation in cells
107
glucocorticoids
* Increase blood glucose by enhancing gluconeogenesis. Decreases glucose consumption in all tissues except the brain. Increases glycogenolysis
108
thyroid hormone
* Stimulate glycogenolysis, stimulates intestinal glucose absorption
109
acetic acid
main source for lipid syntehsis
110
butyric acid
substrate for ketogenesis
111
propionic acid
glucoplastic and substrate for gluconeogensis
112
def of hypoglycaemia
decrease in blood glucose concentration * Cells cannot receive energy and ROS production is increased  further damage of cells * Stimulates the glucoreceptors in the hypothalamus and through neural endings, activates the adrenal medulla and releases: adrenaline, which increases glycogenolysis in the liver. When glycogen stores are spent, precursors of liver glucose synthesis become glycerol from fatty tissue, lactate and pyruvate as well as AA in muscles
113
induce hypoglycaemia
* Induced with hypoglycaemic drugs * Xylitol (in chewing gum) causing severe hypoglycaemia in dogs can cause hypoglycaemic shock and death * Postabsorptional reactive hypoglycaemia occurs after abundant CHO intake, when insulin is released in high conc but too late, so BG drop beneath physiological range * Leucine
114
spontaneous hypoglycaemia
* Deficiency of contraregulative hormones * Caused by endocrinological disturbances like hypoadrenocorticism and hypopituitarism * Causes a decrease in concentration of insulin antagonists * In hypoadrenocorticism, decreased cortisol levels induce decreased gluconeogenesis and increased sensitivity of target cells on insulin  hypoglycaemia * Also occurs when there’s a deficiency of enzymes participating in gluconeogenesis or glycogenolysis
115
hunter dog hypoglycaemia
* Occurs in dog that are hyperactive * Don’t eat before hunting, active during hunting  drop in BG levels * Symptoms: disorientation, weakness, tremors, coma, death and collapse * Disturbance is treated by glucose, or rub gums with honey or fruit juice
116
hypoglycaemia of new born pigletms
* Occurs in first days of life (up till day 3) * Symptoms: apathy, weakness, convulsions, coma and death * Predisposed because gluconeogenetic enzymes aren’t developed in 1st days after birth * In order for it to develop, food must be present in the digestive system * If they receive food during the 1st 10 days of life, piglets can starve up until 3 weeks without developing hypoglycaemia * Depends on: sow, piglet and environment * All conditions (mastitis, metritis, stress) can be indirectly responsible for hypoglycaemia in piglets * Piglets which are born weak and cannot gain access to the sow are also in danger, along with anaemic and infected piglets * High bedding which prevents piglets to move toward the sow
117
gravidity toxemia in sheep (mechanism, signs, treatment)
* Occurs at end of gravidity, particularly in sheep carrying two or more foetuses * Occurs when parturition is close, since glucose is needed for fetal growth * Ovine placenta can extract glucose from blood even when its concentration is low * Ovine foetuses have relatively low blood glucose, the transplacental gradient of glucose – helps transport of glucose from mother to foetus * Decreased food intake predisposes the disease * Hypoglycaemia leads to gluconeogenesis and lipolysis and acetyl CoA accumulation and KB synthesis Signs: apathy and weakness, followed by neurological symptoms Treatment: glucose and corticosteroid application or oral application of glucose precursor
118
def dairy cow ketosis
* Disturbance in carb and fat metabolism. In affected animals there’s a decrease in BG levels and increase KB concentration in blood, urine and milk * Biggest need for glucose occurs at the end of gravidity and beginning of lactation * Glucose is needed for fetal growth and milk production * Dairy cows can be ketotic without hypoglycaemia usually when sub clinic ketosis exists
119
signs of dairy cow ketosis
anorexia, depression, ketonemia, ketolactia, ketonuria, hypoglycaemia and decreased milk production
120
type 1 dairy cow ketosis
- Starvation or skinny cow disease * Insufficient amount of calories needed for lactation, can be primary or secondary * Primary = animal has normal appetite but doesn’t receive sufficient amount of food * Secondary = along with diseases accompanied with appetite loss, most frequent two months after calving
121
type 2 dairy cow ketosis
spontaneous or fat cow disease * Develops at peak of production, in healthy and well-fed animals * Affected animals can spontaneously heal, but production is decreased and susceptibility remains * Repeated ketosis leads to liver damage * Obese cows tend to develop this type, since they have decreased appetite in the critical period, causing NEB due to decreased food intake
122
type 3 dairy cow ketosis
alimentary ketosis * Feeding on rancid silage, abundant with butyric acid, due to clostridial bacteria contamination * Ruminal epithelial has high capacity of activating butyric acid to acetoacetic and beta-hydroxybutyric acid * High conc of butyric acid on ruminal epithelia absorb in bloodstream and ketosis develops as the consequence of toxicity of beta-hydroxybutyric acid
123
pathogenesis dairy cow ketosis
* Hypoglycaemia  glycogenolysis and gluconeogenesis  lipolysis  NEFA go to liver and undergo beta oxidation to ketone, sometimes stored * Net product of B oxidation = acetic acid  activated to acetyl CoA Krebs * Oxaloacetate to end of Krebs – gluconeogenic so when decreased, 2x acetyl CoA fuse  acetoacetyl CoA  HMG-CoA  acetoacetate formed  reduced to B-hydroxybutyrate * Ketones enter brain and muscle  energy * Acidosis, coma and death
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parenterally applied glucose for dairy cow ketosis
* relieve symptoms promptly, as well as oral application of glycerol and propionic acid * GH application decreases ketosis in next lactation, since cows accumulate less fat tissue and more muscles * In NEB more proteins than fat are mobilised as gluconeogenetic substrate * Glucocorticoids can be used as they stimulate gluconeogenesis, glycogenolysis and utilisation of glucose in tissues * Insulin can be used, since lipid mobilisation is decreased and glycolysis is increased
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define hyperglycemia
increase in glucose concentration * Can be physiological (after a meal of easily digestible CHOs, also known as postprandial) or alimentary * After ingestion of CHO rich food, glucose is absorbed through the intestinal epithelia and transported to the liver. If extraction of glucose from the liver is incomplete, glucose enters the bloodstream and hyperglycaemia occurs * Pathological hyperglycaemia can be consequence of insulin deficiency or insulin resistance * Can be induced by some drugs o Ketamine – increases adrenaline secretion o Xylazine and detomidine – inhibits insulin secretion o Progestines increase BG through promotion of gluconeogenesis and stimulation of GH release
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insulin deficiency
* Occurs when there’s damage to the beta cells of the islets of Langerhans in the pancreas * Compromises the mechanisms of synthesis, storage and secretion of insulin * Insulin deficiency occurs in type I diabetes
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insulin resistance
* Condition in which insulins effects are decreased due to decreased sensitivity or decreased response of insulin * Decreased sensitivity to insulin is a condition where a higher conc of insulin is needed for max effect * Resistance occurs when conc of insulin antagonists in the blood are increased, or when receptors for insulin in the target cells are damaged. Both cases, hyperglycaemia occurs
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consequences of hyperglycemia
* Oxidative damage of cells. Kidney threshold for glucose is surpassed, glycosuria occurs and its osmotic activity causes a loss of water  glycosuria is accompanied with polyuria * Glucose is an excellent medium for microorganism growth, prolonged glycosuria is often accompanies with bacterial and fungi infections * Ocular lens, erythrocytes, neurones, digestive system cells, renal cells and beta cells of the pancreas don’t need insulin for glucose transportation, so it enters those cells in an excessive amount and uncontrolled o Enhances sorbitol pathway in cells so that fructose and sorbitol are accumulated o Those substances have a high osmotic activity so water enters these cells, causing swelling, dysfunction and irreversible damage * Prolonged hyperglycaemia results in insulin suppression and pancreatic amyloidosis due to the oxidation of amyloid * Can cause blindness, diabetic ketoacidosis, neuropathies, dehydration, pancreatic amyloidosis, insulin resistance and UTI
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hyperosolar coma (def, mech, treatment)
Def: Life threatening complication of severe hyperglycaemia, occurring in type II diabetics * Insulin action is completely lost due to the cessation of production of insulin or complete insulin resistance o Seen in older patients with acute gastrointestinal diseases with vomiting and diarrhoea, along with polyuria causing dehydration o Dehydration  hypovolemia and decreased glomerular filtration o Decreased glomerular filtration and excretion of glucose in urine  accumulation of glucose in the blood * Neurological symptoms appear as the consequence of dehydration of the brain cells due to hypertonicity of extracellular fluid Treated * Liquid and insulin application
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def DM
metabolic disease characterised with hyperglycaemia as consequence of disturbed insulin secretion, disturbed biological action of insulin or a combination of both disturbances
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type 1 DM
* Insulin dependent * Dogs (older) * Characteristics: hypoinsulinemia and hyperglycaemia * Genetics: immune mediated destruction of pancreatic islets after lymphocytic inflammation and lymphocyte infiltration * Net effect Is insufficiency of beta cells with consequence of hypoinsulinemia, disturbed glucose uptake into cells, increase glycogenolysis and gluconeogenesis and hyperglycaemia with glycosuria
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type 2 DM
* Beginning of the disease with hyperglycaemia and hyperinsulinemia * Advanced stages, hypoinsulinemia occurs as a consequence of beta cell depletion, more common in cats * Obesity is the leading cause, males are more prone too * Treated with oral hypoglycaemic drugs to prevent complications caused by hyperglycaemia
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pathogenesis DM
* Deficiency or dysfunction of insulin in the development * Persistent hyperglycaemia is main diagnostic criterium * Healthy animals, homeostasis is maintained. In diabetic animals - hyperglycaemia * Utilisation of glucose in peripheral tissues is decreased and production in the liver through gluconeogenesis is increased * Glucose is absorbed from the GI tract or synthesised through gluconeogenesis or released through glycogenolysis and accumulates in the blood * Utilisation of glucose in the tissues is decreased, therefore glucose remains in the blood * Deficiency/dysfunction of insulin progresses, balance of glucose in the blood is taken to a higher level and finally exceeds the renal threshold * Glycosuria begins, glucose has osmotic activity so polyuria develops * Animal compensates by drinking more water or polydipsia * Since glucose cannot enter cells and utilisation is decreased, there’s energy disbalance. Catabolism of lipids and proteins begins. Lipomobilisation occurs, depending on the insulin deficiency, since insulin stops the activity of lipoprotein lipase. Due to high lipoprotein concentration in the blood, plasma become turbid and levels of total triglycerides and cholesterol increases * Protein catabolism begins and AA are used as gluconeogenic substrate which leads to muscular weakness and weight loss * Since glucose cannot be transported into neurons sensitive to glucose in the hypothalamus due to lack of central insulin action on appetite regulation, although hyperglycaemic, animals are hungry and polyphagia develops
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acute complications of DM
* severe hyperglycaemia and severe hypoglycaemia * type 1 have glycosuria, increased fat catabolism, severe ketogenesis which can lead to diabetic ketoacidosis, coma and death * diabetes type II, stress, infection or corticosteroid application can induce severe hyperglycaemia, dehydration and hyperosmolarity which can progress to hyperosmolar coma, usually in older patients.
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chronic complications
* connected to vascular damage, present as micro or macrovascular damage * diabetes enhances large BV atherosclerosis which then causes coronary diseases, stroke and extremity diseases which are a consequence of poor circulation diabetic retinopathy diabetic neuropathy diabetic nephropathy
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diabetic retinopathy
o small BV in back of the eye release proteins and blood into the retina, along with microaneurysms and neovascularisation o spontaneous bleeding from young BV can lead to scar formation on the retina and retinal ablation o cataracts and glaucoma
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diabetic nephropathy
o in the beginning, small renal BV walls become more permeable, therefore proteins and urine leakage begins o later stage, filtration is decreased and lost o toxins accumulate in blood which leads to azotaemia and patients need dialysis o can be controlled through BP control
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diabetic neuropathy
o consequence of decreased circulation and ischemic damage of the nerves as well as sorbitol pathway activation and swelling of neurones o symptoms include insensitivity, burning sensation or pain in the feet or legs
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obesity
* Body mass of an organism exceed the ideal by 20% it’s a consequence of increased food intake and decreased energy consumption, particularly early age, while GH is secreted * Fat tissue formed in young animals is hard or impossible to lose since fat cells can only undergo atrophy * If fat tissue is accumulated after the growth is accomplished, it’s easier to lose it * It can occur when satiety centre is disturbed (Prader Wili’s syndrome) * Expression of insulin sensitive GLUT4 in muscles and fat cells of obese cats is significantly lower compared to cats with normal body weight * In liver and muscle cells of obese cats, there’s lower expression of insulin signalling genes * Fat tissue is endocrinologically active and secretes numerous bio mediators o Secretes: adipokines (leptin, resistin, adiponectin) and proinflammatory cytokines (TNFa, interleukins 1,6,9) * Levels of adiponectin produced only in fat tissues is decreased in obese and diabetic cats  insulin resistance and chronic inflammatory processes in the organism * Adiponectin increases insulin sensitivity in cells and has anti-inflammatory effects * Leptin levels are higher than in healthy cats and leptin action is decreased * Leptin is also involved in insulin sensitivity * Insulin resistance as a consequence of obesity is reversible  progress to diabetes
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diabetic ketoacidosis def and treatment
: life threatening complication of diabetes when there’s an accumulation of KB in blood, causes metabolic acidosis and disturbances in electrolyte concentration treatment: liquid electrolytes and insulin application
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pathogenesis of DKA
* Clinically presented with PUPD, vomiting, diarrhoea, anorexia, dehydration, ketonuria and later stages with lethargy, weakness, epileptic seizures and coma * Increased FA mobilisation due to the lack of liporotective effects of insulin causes increased beta oxidation of FA in the liver and decreased synthesis * The conc of AcCoA increases and ketogenesis with abundant synthesis of acetoacetic acid, beta hydroxybutyric acid and acetone begin * Peripheral tissues of diabetic animals have a lower capacity of ketone utilisation * Acetoacetic acid and beta hydroxybutyrate are acidic anions and their increase leads to the decrease of other anions like bicarbonates, sodium and chloride ions in the blood * Decreased levels of bicarbonates in the blood stimulate the respiratory centre and cause hyperventilation with deep and laboured breathing in order to correct the metabolic acidosis * When respiratory compensation fails, acidosis develops * Renal threshold for ketones is low and they are lost in urine, along with water and bicarbonates * Acidic ketones are buffered with ammonia ions from glutamine in the renal tubules and so large amounts of ketones are lost along with sodium and potassium * Water and electrolyte lost due to polyuria can cause hypovolemic shock. Increased plasmatic osmolarity due to hyperglycaemia in renal failure can cause transition of water from the cells to the blood and intracellular dehydration of cerebral neurones and hyperosmolar coma
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causes of fat malabsorption
* Can be deficiency of biliary acid salts, insufficiency of exocrine pancreas and disturbances in fat transportation * Deficiency of biliary acid salts occurs during obstruction of bile ducts with stones, parasites, tumours, during catarrhal enteritis when Odie’s orifice is closed and bile cannot be transported to duodenum * Can be a consequence of decreased bile synthesis during liver disease * Bile acid salt deficiency decreases fat emulsification, lipase action and absorption, therefore undigested fat is present in faeces (steatorrhea) * Decreased lipase secretion or its deficiency in degenerative and necrotic processes in pancreas or due to obstruction of duct
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hyperlipoproteinemia (primary rare), secondary
* Are symptoms of other diseases, such as acute pancreatitis, liver diseases, DM, hypothyroidosis and hyperadrenocorticism in dogs * Acute pancreatitis: hypercholesterolemia or hypertriglyceridemia occur but mechanisms isn’t clear. Hyperlipoproteinemia induced by other disorders can predispose the animal to pancreatitis, can be due to obstructive cholestasis. Decreased intravascular lipolysis or processing of plasmatic lipoproteins leads to increased concentration of VLDL or chylomicrones * Hypercholesterolemia is frequent found in cholestasis along with hypertriglyceridemia. It’s considered to be due to increased cholesterol production in liver, decreased secretion in bile and disturbed intake of LDL In hepatocytes
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hypolipoprotenami
* Occur due to decreased cholesterol production and hypoadrenocorticism * Hypocholesterolemia during protein loss enteropathies includes decreased lipoprotein production due to catabolic state, if lymphangiectasis occur, loss of lipids produced by enterocytes occurs
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definition of atherosclerosis (who affects and consequences)
Def: chronic progressive arterial disease characterised with deposition of some lipid metabolism products in arterial walls and deformations of arterial walls * Middle and old age, herbivorous and omnivorous * Consequences: stroke and cerebrovascular insult, could less seriously cause ischemia or necrosis
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risk factor of atherosclerosis
* Hypercholesterolemia, increased hydrostatic pressure and presence of glycolyzed proteins, increasing ROS production
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pathogenesis of atherosclerosis
* Response to endothelial damage * Occurs when elevated blood pressure * Damaged endothelium allows LDL to enter, monocytes eat LDL and cholesterol, dies and forms foam cells * Release cytokines  foam cells build up, forming fatty streak which is thrombogenic * Platelets enter, release PDGF  encourage smooth muscle growth, secretes collagen, proteoglycan and elastin = fibrotic cap * Fibrous cap + fatty streak = plaque
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equine metabolic syndrome
* Obesity caused by excessive eating and changes in lifestyles in horses * Along with insulin resistance, manifestation of laminitis * Insulin resistance means disturbances in insulin signalisation, including decreased activit of tyrosine kinase insulin receptor and decreased postreceptive phosphorylation with changes in metabolic and vascular insulin effects * In horses with insulin resistance significantly lower expression of GLUT4 at the surface of muscular and fat cells is noted * Compensated insulin resistance is a condition in which pancreas produces more insulin, in combination with decreased insulin clearins it leads to hyperinsulinemia * Decompensated insulin resistance characterises pancreatic insufficiency, hypoinsulinemia and type II (rare in horses)
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equine metabolic syndrome symptoms
* Obesity, particularly in the neck region * Laminitis = inflammation of lamellar structures of the hoof, characterised by sudden lameness without visible mechanical cause and increased hoof temperature (condition is painful) * Polyuria and lethargy
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cause of laminits
Cause: indigestion due to large amount of easily digestible carbohydrates consumptions, increased physical activity and stress * Abundant amounts of easily digestible carbs results in increased fermentation of undigested carbs in caeca and accumulation of lactic acid
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pathogenesis of laminitis
* Increased lactic acid concentration, endotoxins and exotoxins concentration leads to circulatory disturbances, particularly in legs and consequent laminitis * Early stages in acute laminitis are ischemia of laminar arteriolas and venulas * Arterial blood is shunted to venous return through numerous BV anastomoses in hoof and bypasses corium * Laminitis during equine metabolic syndrome is a result of vascular dysfunction o Primary insult is related to changes in BV function due to hyperinsulinemia, which decreases circulation in hoof o Insulin can cause vasoconstriction through sympaticus stimulation and by activation of nitrogen activated protein-kinase pathway
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protein deficiency
due to" - decreased production - decreased AA utilisation - immobilisation - due to ancrease loss of proteins
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protein deficiency due to decreased production
* Can be due to a decreased intake of AA from the diet or incomplete absorption in the intestinal mucosa during some GI disease * Dietary deficiency occurs in starvation, when are nutrients are deficient, or starvation with mainly protein deficits * Due to CHO deficiency, insulin secretion is decreased and its anabolic effect on proteins is absent, therefore protein catabolism increases * AA are used as substrates for gluconeogenesis or plasma protein production * During general starvation, hypoproteinaemia will appear after a quarter of total muscle mass is lost * If starvation is mainly due to protein deficiency, insulin is released preserving muscular mass from degradation * Few AA for plasma protein synthesis is available and hypoproteinaemia will appear * Young animals are particularly sensitive, during growth and development since the need for protein is huge
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protein deficiency due to decreased AA utilisation
* After absorption, AA are transported ot the liver * Liver supplies the body with AA and plasma proteins * During liver insufficiency, disturbances in AA and proteins metabolism impact the whole animal * It’s particularly visible as swelling which is due to hypolbuminaemia and oncotic pressure decrease, and increased prone to bleeding due to decreased production of coagulation factors
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protein immobilisation
* During immobilisation, muscles become atrophic and bones osteoporotic due to metabolic loss of proteins as a consequence of decreased synthesis and increased catabolism
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increased loss of protein
* Proteins can be directly lost during severe bleeding, plasma loss, proteinuria, through the digestive system or effusions into body cavities * Indirect loss happens during increased catabolism
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consequence of protein loss
* Due to metabolic adaption of the tissues, proteins are not equally lost from all tissues * Loss of muscle mass and strength, bones become visible * Albumins maintain oncotic pressure and extracellular fluid distribution, therefore during hypoalbuminemia, edema occurs * Decreased calcium binding during hypoalbuminemia leads to hypocalcaemia but concentration of ionised calcium remains normal and tetany will not occur * Hypoalbuminemia increases toxic effects on unconjugated bilirubin since there’s a lack of albumin transporter for unconjugated bilirubin transport * During protein deficiency, globin synthesis and erythrocyte production is decreased and anaemia occurs, due to decreased immunoglobin production, there’s an increased risk of infections
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equine paralytic myoglobinuria
* Acute disease manifested with sudden paralysis of striated muscles and in severe cases with myoglobinuria * clinical signs are appearing after 15-30 minutes after exercise * animals are straining whilst trying to urinate, don’t want to move and in severe cases = colic * pain, distress, clenched muscles of the hindlimbs is also visible * diagnosis is confirmed after lab tests on blood and urine: increased creatine kinase, AST, LH * chronic = due to inherited dysfunction triggered by the environment
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pathogenesis of equine paralytic myoglobinuria
* due to myofibril destruction, myoglobin enters the blood and myoglobinemia occurs * since the renal threshold for myoglobin is low, myoglobinuria soon manifests * clinical signs affects horses include lameness and stiff hindlegs, painful muscles when palpated and usually recumbent * pectorals may also be impaired * pathological changes vary from severe necrosis to signs of regeneration
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therapy of eqine paralytic myoglobinuria
* based on pain relief, correction of electrolytes and acid-base balance, prevention of renal damage caused by myoglobinuria and dehydration as well as NSAID
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sporadic paralytic myoglobinuria
* Overwhelming physical activity * Electrolyte balance caused by inadequate diet or loss in sweat * Selenium and Vit E deficiency * Excessive CHO intake that are easily digestible * Hormonal disbalance due to oestrus * Lactic acidosis * Environmental factors are important
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chronic paralytic myoglobinuria
* Caused by a glycogen storage disturbance (polysaccharide storage myopathy)
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undernourishment
* Condition in which the intake of essential nutrients is inadequate * Can be primary (acute or chronic, depending on nutrient insufficiency) or secondary
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during acute starvation
* Depends on quality and quantity of ingested food and if it persists it causes chronic starvation. First phase :irritability, depression and stupor. Glycogen is the first energy source used, then lipid and protein catabolism follow, so body mass is reduced. Lipomobilisation and increased ketogenesis can result in metabolic acidosis * Animal adapt to low energy intake by decreasing BMR through decreased secretion of thyroid hormones and other hormones * Insulin secretion is decreased and glucose entrance in all the tissues except the brain is reduced. * Free FA and AA levels in the sera increase * Substrates are used in gluconeogenesis in the liver * Secretion of glucocorticoids, glucagon and GH increases resulting in gluconeogenesis and decreased glucose utilisation in tissues
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during chrinic starvation/general undernourishment
* primary or secondary to other disease, gluconeogenesis is activated and lipid catabolism is increased * brain tissue utilises ketones in a larger extent * if proteins are unavailable, especially albumins, hypoproteinaemia with consequent oncotic pressure decrease can occur resulting in edema and ascites * decreased glomerular filtration contributes to water accumulation in the organism * intestinal villi undergo atrophy, which can lead to additional protein loss, disturbances in digestion and absorption * secretions of the pituitary gland, thyroid gland, pancreas and sexual organs is disturbed
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acute rumen acidosis
* Occurs when there’s feed rich in carbohydrates which increases the amyloltic bacteria population and increases the production of lactic acid * Lactic acid build-up causes a drop in pH * Compensatory mechanisms by the rumimant = loss of appetite to reduce feed intake = increase of saliva which has bicarbonate and phosphate as buffers, =better absorption of VFAs and the proliferation of bacteria which converts lactate to VFAs o Lactic acid is absorbed into the blood and causes metabolic acidosis o Lactic acid fermentation increases osmotic pressure, inhibits water absorption from the rumen into the blood, causes dehydration, haemoconcentration, intoxication and osmotic diarrhoea o Endotoxins increase the concentration of VFAs and lactates, further decrease the pH and cause high osmotic pressure leading to ruminitis
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clinical signs of acute rumen acidosis
* Loss of appetite and inhibited rumination * Rumen hypomotility with retention of content * Ruminitis = inflammation and ulceration of the mucous membranes of the rumen. Bacteria enter the blood, cause liver abscesses, changes in the lungs, heart, kidneys and joints * Dehydration * Metabolic acidosis and intoxication * Loss of coordination, general weakness, shock and death
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chronic rumen acidosis
* Occurs after increased production of VFAs in the rumen 2-3 hours after a meal rich in easily digestivle carbohydrates * Decreases the pH and limits the absorption of VFAs and pH return to physiological limits * Continuous administration of poorly balanced meals leads to permanent production of larger amounts of VFAs and the onset of clinical signs
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clinical signs of chronic rumen acidosis
* Ruminitis = fibrous thickening of ruminal mucosa and loss of papilla * Ruminal parakeratosis = papillae are enlarged and hardened, several can adhere together to form bundles, reducing the absorption of nutrients * Low milk fat due to inhibition of fatty acid synthesis in the mammary gland * Laminitis = histamines and endotoxin damage of endothelium of BV underneath the hoof wall leads to ischemia and necrosis of the lamina * Demineralisation of bone = degradation of the bone in order to release bicarbonate ions
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rumen alkalosis
* Excessive production of ammonia in the rumen * Can be due to an unbalanced meal (rich in protein, poor in CHO), improper application of urea, taking larger amounts of food where E.coli and vulgaris outgrow normal flora of rumen and generate a large amount of ammonia * Foods rich in proteins increases proteolytic activity in the rumen, increase ammonia concentration and increase pH above 7 * Ammonia is then absorbed into the blood and given to the liver for detoxification * Ammonia is also used to create glutamic acid along with alpha-ketoglutarate from the citric acid cycle, which then converted to GABA * An increase in GABA causes hypoenergosis of the brain, leading to excitation and spams Clinical signs (10 mins after a meal rich in urea) * Polyuria, disorder of rumen motility, strong abdominal movements, cyanosis, foam on the nose and mouth, hypersensitivity to sound, muscle tremors, heavy breathing and paralysis  death Subclinical form: * Decreased appetite, hypotony and atony of the rumen, recurrent bloat, decrease in milk production, diarrhoea, paresis and possible development of metabolic alkalosis
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frothy bloat
* Caused by abnormal fermentation of carbs and proteins * There’s some sudden production of a large amount of gas, which is trapped in little bubbles within the rumen * Stable foam layer is formed in the rumen so eructation cannot occur, there’s rapid expansion of the rumen and reticulum * Soluble leaf proteins form monomolecular layers around the gas bubbles * Salivary mucin is antifoaming, but production of saliva is reduced at this point * Bloat producing pastures are more rapidly digested and may release a greater amount of small chloroplast particles that trap gas bubbles and prevent their coalesce * Frothy bloat occurs most commonly in animals grazing legumes like alfalfa * In feedlot cattle, less commonly in dairy cattle, frothy bloat occurs on high grain diets * There’s no separation of gas and a foam layer is formed, so there’s no eructation and there’s increased pressure in the rumen, this increases rumen motility * The increased pressure and stretching of the wall slows down the contraction of the rumen causing hypotonia and finally atony of the rumen * Increased intraruminal pressure increases intraabdominal pressure, putting pressure on vena cava caudalis lumen, reducing blood flow back to the heart, decreasing minute volume and reduced perfusion to vital organs, like the lungs, leading to dyspnoea and hypoxia * Increased intraruminal pressure causes the production of a large amount of CO2 in the rumen, leading to hypercapnia, and stimulates the respiration centre, causing dyspnoea and hypoxia * Increased intraruminal pressure increases intrathoracic pressure, reducing breathing capacity and leading to dyspnoea and hypoxia * Death from frothy bloat occurs due to suffocation
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free gas bloat
* Caused by some obstruction of eructation * Eosophagel obstruction due to foreign body * Stenosis or pressure from some enlargement outside of the oesophaus * Damage of the vagus nerve and nerve pathwyas involvedin the eructation reflex * Diaphragmatic hernia * Tetanus * Leisons of the reticular wall * Ruminal atony that occurs in anaphylaxis and in grain overload, causing a decrease in rumen pH and possibly esophagitis and ruminitis that can interfere with eructation Acute bloat is the complete inability to remove gases, Chronic bloat is the partial inability to remove gases and the bloat develops progressively
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traumatic reticuloperitoniitis
* Perforation of the reticulum with a sharp foreign body like a wire or nail * Ruminant swallows some metal object which falls directly into the reticulum or passes into the rumen and is carried into the reticulum by ruminal contractions * Reticulo-omasal orifice is elevated, which tends to retain heavy objects in the reticulum * Honeycomb-like reticular mucosa traps sharp objects * Contractions of the reticulum causes the penetration of the wall by the foreign object * There’s then leakage of ingesta and bacteria contaminates the peritoneal cavity leading to peritonitis and adhesions * Can penetrate the diaphragm and enter the thoracic cavity and pericardial sac * Liver or spleen may be pierced and infected resulting in abscessation or septicaemia
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clinical signs of traumatic reticuloperitonitis
* Sudden onset of ruminoreticular atony and sharp fall in milk production * Decreased faecal output * Rectal temperature is often mildly increased * Cow has arched bac, anxious and unwilling to move * Forced sudden movements as well as defecating, urinating, lying down, getting up and stepping over barriers may be accompanied chronic cases * Feed intake and faecal output are reduced and milk production remains low * Signs of cranial abdominal pain become less apparent and the rectal temperature returns to normal * Some cattle develop vagal indigestion syndrome because of the adhesion that forms after foreign body perforation
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signs of pleuritis and pericarditis
* Depression, tachycardia * Pleuritis is manifested by fast, shallow, respiration, muffed lung sounds and pleuritic friction * Traumatic pericarditis is most commonly characterised by muffled heart sounds * Jugular vein distension and congestive heart failure with submandibular edema * Penetration through the pericardium into the myocardium usually results in extensive haemorrhage into the pericardial sac or ventricular arrhythmia and sudden death
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regenerative anaemia def
* Means that the bone marrow is responding to the lack of RBCs in the blood * Can be seen as increased reticulocytes * Polychromatophils are usually not seen in horses, cattle, sheep and goats, more in dogs and pigs * Polychromatophils are never seen in horses * Higher MCV
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hemolytic regernative anaemia causes
* Immune mediated haemolytic anaemia * Erythroparasites * Other infectious agents * Oxidation injury * Fragmentation injury * Histiocytic disorders * Inherited RBC defects * Metabolic conditions
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hemorrhagi regenerative anaemia causes
* Trauma * GI bleeding from neoplasia, NSAIDs, renal disease * Urogenital bleeding * Coagulopathies from liver disease, rodenticides toxicity * Chronic external blood loss leads to poorly regenerative, or nonregenerative iron deficiency anaemia
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non regenerative anaemia
Decreased production of bone marrow due to systemic disease (2) * Inflammatory disease, nutritional deficiency, chronic kidney disease, metabolic/endocrine disease, anaemia’s associated with FIV and FeLV Decreased production of bone marrow from primary bone marrow disease: (3) * Pure RBC aplasia, aplastic anaemia due to retrovirus, myelodysplastic syndrome Nonregen anaemia due to decreased production has several mechanisms: * Insufficiency production or activity of erythropoietic substances due to chronic kidney disease * Erythropoiesis suppression due to drugs, cytokines and tumours * Nutritional deficiency, especially in Fe and Cu * Defective Hb synthesis usually secondary to Fe deficiency * Defective DNA synthesis * Destruction of bone marrow haematopoietic cells * Replacement of haemopoiesis due to neoplasia
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hemolytic anaemia def
* Intrinsic anaemia: hereditary Stomatocytes, pyruvate kinase deficiency * Extrinsic anaemia: primary autoimmune haemolytic anaemia, secondary immune mediated, alloimmune (neonatal erythrolysis) fragmented haemolytic anaemia, infection * Destruction or removal of RBC from the bloodstream. Can be intravascular or extravascular * Can cause haemolytic icterus
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extravascular hemolytic anaemia
* Phagocytosis of RBCs with the destruction inside macrophages * Occurs within the bone marrow, spleen or liver * Hb cannot escape into the circulation and common symptom is splenomegaly o Antibody coated or irregular RBC, phagocytosis by macrophage, degradation In lysosome, intracellular haemoglobin, biliverdin leaves macrophage to hepatocytes and bilirubin biliary clearance
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intravascular hemolytic anaemia
* There’s destruction of RBCs within the blood vessels leading to haemoglobinemia, haemoglobinuria and decreased haptoglobin * 1. RBC in circulation * 2. Direct lysis by stress, toxins or compliment activation * 3. Intravascular free Hb * 4. Bounds to haptoglobin for hepatic clearance * 5. If too much Hb for haptoglobin, renal excretion leading to haemoglobinuria
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neonatal isoertyhrolysis
* If parents have different blood types and the neonate inherits the blood group of the sitre * The colostrum then will contain antibodies against the baby’s RBC and it occurs in horse, cat, dogs, cattle and pigs * In foals born to mares of different blood type to the stallion, the mare is sensitised to the stallion\s blood group most often through previos preganncies or at delivery causing retroplcental bleeding, where the foal’s blood comes into contact with the mare’s circulation during the last weeks of pregnancy * In kittens type B queens mate with type A or AB toms, so the kittens have anti A antibodies causing haemolysis after ingestion of colostrum causing fading kitten syndrome * Noticeable sign is ear and tail tip necrosis, most signs occur within 24-36 hours after birth, after the suckling of colostrum * Neonates are weak, have pale mucous membranes, tachycardia, tachypnoea, haemoglobinuria and hemoglobinemia
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oxidant - induced haemolytic aanemia
* Onions (dogs, cat), brassica species (rum), nitrate containing plants (rum) * Minerals = zinc (dogs), copper (sheep, dog) * Chemical = skunk musk * Drug = acetaminophen (cats), Vit K (dogs)
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sideropeni anaemia
* Occurs when iron is too limited for erythropoiesis * Occurs in the absence of iron, so Hb cannot be produced in sufficient quantities * Causes microcytic hypochromic anaemia * Immature RBCs in the bone marrow stop dividing once a critical concentration of Hb is reached within the cell, so iron deficiency ends up causing more divisions of the progenitor RBCs resulting in smaller mature RBCS * RBCs are shrunken and have membrane blebbing, which are features of apoptosis. Increased mechanical fragility is seen as keratocytes, acanthocytes and schistocytes Regenerative * When there’s sufficiency iron absorbed or there’s blood loss in the upper GI tract, since some iron and blood can be absorbed by the intestines Non-regenerative * With concurrent nutritional iron deficiency and other diseases that suppresses regeneration of RBCs
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causes of sideropneic aanemia
* Decreased intake of iron (in new-born animals, like puppies and piglets) * Decreased absorption of iron (insufficient HCl secretion and IBD) * Blood loss * Increased demand of iron
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iron deficiency anameia in piglets
Sows * Have a low permeability of the transplacental barrier * Milk contains small amount of iron Piglets * Born with very low iron stores, sufficient for only 4 days Environment * Pigs raised in confinement without access to soil or faeces containing iron will lead to iron def Pathophysiology * Rapid expansion of plasma volume due to colostrum * Insufficient iron supply = microcytic hypochromic anaemia * Tissue hypoxia * Underdeveloped glucostatic regulation (hypoglycaemia) * Fe is a coenzyme of gluconeogenic enzymes * Hypothermia * GI inflammation or parasites interfere with absorption Clinical signs: * Decreased appetite, inadequate efficiency of food utilisation, stunted growth, tremors, anaemia, pulmonary edema, dilation of the hart and drop in blood pressure and death
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anaemia of chornic disease
* Inflammatory diseases can cause mild to moderate normocytic normochromic anaemia that’s usually nonregenerative * TNF alpha, IFN gamma, IL1 and IL6 are mediators of this anaemia * Mechanism: 1. Decreased RBC lifespan and 2. Decreased RBC production * Toxins, inflammatory cytokines, compliments and free radicals induce direct RBC damage by binding to the surface of the RBX leading to extravascular haemolysis * Decreased RBC production occurs due to the suppression of erythropoiesis by inflammatory cytokines * Iron homeostasis becomes disturbed as there’s decreased absorption of iron and iron sequestration within macrophages * Hepcidin causes a decrease in iron concentration * Cytokines also inhibit the release or production of erythropoietin from the kidneys * Hyperglobinemia, hypoalbuminemia decreased iron, increased APP * Causes nonregenerative anaemia with echinocytes * As kidneys go through some disease, there’s decreased erythropoietin production. Meanwhile, inflammatory cytokines cause the increased activation of hepcidin which further suppresses erythropoiesis by using up Fe stores. Toxins from uraemia during chronic kidney disease as well as cytokines also directly suppresses erythropoiesis * Uremic toxins promote extravascular haemolysis, so RBCs are dying earlier on
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aplastic anaemai
* Characterised by pancytopenia, leukocytopenia and thrombocytopenia * Most common mechanism of aplastic anaemia is autoimmune destruction of the hematopoietic stem cell * Causes are mostly idiopathic but can become induced by infection, drug therapy, toxin ingestion, genetic disorders, radiation or immune mediated
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pure red cell aplasia
* Total absence of identifiable erythroid precursors in marrow * Only the erythroid line is affected * Causes severe nonregenerative normocytic normochromic anaemia
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thrombocytopenia
1. Decrease bone marrow production = diseases, infections, drugs 2. Increased platelet consumption = extensive bleeding, DIC 3. Increased platelet destruction = immune mediated Pseudo-thrombocytopenia * Platelet clumping in vitro (cats – venipuncture)
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von willebran dsiease
* Inherited disease * Disorders of primary haemostasis * Spontaneous mucosal bleeding * Slow wound healing * vWF def = decreased platelet plug formation * class; o type 1 = deficiency in amount of vWF o type 2 = more severe o type 3 = complete absence and most severe
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sinus tachycardia (+ cause)
* Increased rate of the SA node pace * Production of impulses is faster, but regular * Increases CO * Extreme heart rates can reduce SV and CO, SV becomes reduced because of decrease ventricular filling time * Excessive shortening of certain phases of cardiac revolution decreases cardiac output, causes ischemia of the heart and causes heart failure Causes: * Increased body temperature (increases metabolic speed and oxygen consumption) * Physical exercise or stress (increases concentration of catecholamines in the blood) * Hyperthyroidism * Anaemia and pregnancy
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sinus bradycardia
* Slow production of impulses by SA node Can indicate a pathology of the heart of pathology of the system that controls its rate: * Reduced irritability of the sinus node (beta blockers and the cold) * Hypothermia * Hypofunction of the thyroid gland * Increased intracranial pressure * Jaundice
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respiratory sinus arrhythmia
* Change of the rate of spontaneous depolarisation in the SA node related to respiration * Increased respiratory volume during inspiration causes inhibition of vagal neurones and sympathetic system becomes dominant during inspiration * Reflux influences from slowly adapting stretch receptors in the lungs – during inspiration they inhibit activity of the cardioinhibitory centre and it leads to the dominance of cardioexcitatory centre * Helps to stabilise CO by allowing the heart rate to increase during inspiration when the left ventricular SV decreases Brainbridge’s reflex * Distension of the right atrium by increased venous return in inspiration leads to the acceleration of the heart rate by local and reflex mechanisms * Negative pressure in the chest during inspiration leads to the augmentation of the venous return from lower parts of the body
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sinus arrest
* Medical condition where the SA node of the heart transiently ceases to generate electrical impulses * Since the heart contains multiple pacemakers, the interruption of the cardiac cycle generally lasts only a few seconds before another part of the heart with lower automacy begins pacing and restores the heart action * Manifestation of the sinus arrest on an ECG is a brief period of irregular length with no electrical activity before either the SA node resumes normal pacing or another pacemaker begins pacing * If no other pacemaker begins pacing during an episode of sinus arrest, it becomes a cardiac arrest Common causes: * Strong activation of the vagus nerve or increased sensitivity of the SA node to acetylcholine * Damage of the SA node by disease: ischemia, inflammation, degenerative changes and toxic influences
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passive hetertophy
* When sinus node fails in its role as a pacemaker, latent pacemakers can drive the heart and an escape beat is arising from an ectopic focus in the atria, the AV junction or in the ventricles * Ectopic impulse in this instance is always late appearing only after the next anticipated sinus beat fails to materialise * If sinus node failure is only brief, the ectopic focus may generate only a single escape beat * If the sinus node failure is prolonged, the ectopic focus produces a rhythm of escape beats to assume full pacing function * This escape mechanism offers protection against total cardiac standstill in the event of sinus node failure * Reduced heart rate: slower firing rate of latent pacemakers * Preuatomatic pause: ECG will show passive heterotopic activity from latent pacemaker with a delay
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active heterotopy
* Impulses depolarising heart muscles are produced outside of the SA node and they are produced faster than is the normal rate of the SA node * Consequences of lack of ATP and membrane dysfunction lead to the reduction of the resting membrane potential. Types of arrhythmia caused by active heterotrophy depends on the site of origin: supraventricular vs ventricular Causes and mechanism: * Reduction of the resting membrane potential * Change of automaticity * Change of refractory phase
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supraventriuclar arrhythmia
* Atrial extrasystole or premature atrial depolarisation * Supraventricular tachycardia * Atrial flutter * Atrial fibrillation * Production of extra beats in the atria or AV junction zone. They differ only by the number of produced impulses. Isolated impulses lead to premature atrial depolarisation while permanent pacing will lead to supraventricular tachycardia. They can be produced by one ectopic focus of beats or more than one ectopic foci. More than one ectopic focus may indicate that the damage of the atria and AV zone is more serious
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atrial flutter
* Disturbance of the electrical activity of the heart caused by ectopic focus with even higher activity than is typical for common tachycardia * Depolarisation spreads across the muscle, which is not optimally repolarised after previous depolarisation, which is why the ECG shows specific type of the P waves with a saw tooth shape * If AV zone loses its filtering ability, all the impulses will go to the ventricles with serious reduction of the CO due to extremely short, diastolic phase and may lead to heart failure and even cardiogenic shock
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trial fibrillation
* Arrythmia caused by irregular production of impulses in multiple foci in the atria independently and these foci are producing impulses during systole and diastole * Irregular contraction of the ventricle * Ventricular filling is limited with passive inflow of blood leading to a decrease in CO as well as a drop in BP
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ventricular flutter
* Caused by high rate of one ectopic focus in the ventricles * Activation of ventricles with such a high rate doesn’t allow an effective contraction nor relaxation of the muscle and also limits diastolic filling * CO is reduced to nearly 0, there’s considerable hypoperfusion in the systemic circulation
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ventricular fibrillation
* Fatal arrhythmia caused by the uncoordinated activity of multiple foci of extra activity of the ventricles * Result is chaotic activation of small fields of musculature around the foci, ventricle fails to produce any effective contraction and pressure – zero CO = circulation stops
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mechanism leading to imparied condutons
* Decrease in resting membrane potential towards zero * Presence of inflammatory infiltrate * Accumulation of amyloid * Excessive fibrosis in the heart * Hypertrophy and dilation * Change of ion channel function
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sinbus block
* Disturbance in which the impulses are generated in the sinus node, but for some reason they cannot be conducted to atrial muscle 1st degree * Delayed conduction from SA node to atrial muscle * No haemodynamic effect * ECG may show sinus rhythm or sinus bradycardia 2nd degree * Inability to conduct some of the SA node generated impulses to the atria * There’s occasional lack of conduction which is seen as a lack of the P QRS and T on the ECG * Haemodynamic impact depends on how many times the impulses are not conducts 3rd degree * None of the electrical impulses are conducted to the atria * There’s activation of the secondary pacemaker in the AV zone with junctional rhythm * Clinical manifestation can be cardiogenic syncope, a transient loss of consciousness caused by reduced cerebral blood flow with a tendency to spontaneously recover mainly after secondary rhythm
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AV block
* AV block is the partial or incomplete interruption of the impulse transmission from the atria to ventricle 1st degree * Delay of atrioventricular conduction * This is seen as a prolonged P-Q interval 2nd degree * Some impulses that reach the AV zone are not conducted to the ventricle * Some of the P wave are not followed by QRS complexes Mobitz type 1 * Progressive slowing of the conduction in the AV zone from beat to beat until the conduction of impulse fails * This repeats periodically in cycles * There’s progressive prolongation of the PQ intervals, until there’s no QRS complex following the P wave Mobitz type 2: * Presence of prolonged PQ intervals, all equal but some of the P waves aren’t followed by QRS complex * There’s a high risk that this block can become a complete AV block 3rd degree: * Completely inability of the AV zone to conduct impulses * Impulses are normally produced in the SA node, but cannot be conducted to the ventricles * Complete AV block, if not followed by activation of alternative pacemaker, will lead to asystole and stokes Adam syndrome * The ventricular rhythm usually begins after several seconds and this interval is = Preuatomatic pause * Atria are depolarised by the impulse from the SA node in a normal pacing process, but ventricles are depolarised from the ventricular conductive system * There’s no relationship between atrial and ventricular depolarisation = atrioventricular dissociation
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valvular stenossi
* Occurs when the tissue forming the valve leaflets become stiffer, narrowing the valve opening and reducing the amount of blood that can flow through it * Can cause obstruction of blood flow and as a result the chamber behind the effected valve must build up more pressure to overcome resistance (leads to valvular insufficiency)
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valvular insuffieicny
* Occurs when the leaflets don’t close completely letting blood leak backwards across the valve * Backward flow is referred to as regurgitant flow * Causes blood flow to flow retrograde, the heart chamber which received the additional retrograde flow is then forced to pump the added regurgitant volume together with the volume being received
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mitral stenosis
* Decreased mitral valve area * Impairment of blood flow to the left ventricle * Left atrial hypertrophy as compensation * Increased pressure and volume in the left atrium * Increased pressure in the pulmonary veins and capillary bed leading to pulmonary edema * Hypertrophy and dilation of the right ventricle * Relative insufficiency of the tricuspid valve * Regurgitation of blood into the right atrium * Systemic venous congestion leading to edema
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mitral insufficiency
* Mitral valve fails to close properly * Regurgitation of blood into the left atrium * Hypertrophy and dilation of the left atrium and ventricular wall for compensation * Increase of blood in left atrium * Elevation of pulmonary capillary pressure leading to pulmonary edema * Hypertrophy and dilation of the right ventricle for compensation * Relative insufficiency of the tricuspid and mitral valve * Decompensation of the left and right side of the heart * Congestive heart failure and edema
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aortic insufficiency
* Semilunar valves fail to close properly * Blood flows in reverse direction during ventricular diastole * Left ventricular eccentric hypertrophy for compensation * Diastolic murmur * Relative insufficiency of mitral valve * Dilation of the left atrium * Elevation of pulmonary capillary pressure leading to pulmonary edema * Hypertrophy and dilation of the right ventricle * Relative insufficiency of the tricuspid valve causing edema
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aortic stenosis
* Obstruction of blood flow across the aortic valve * Left ventricular pressure overload * Left ventricular concentric hypertrophy leading to compensation * Atrial contribution for compensation * Systolic murmur * Decompensation due to inadequate supply of the heart muscle with oxygen and nutrients leading to coronary insufficiency
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hypertrophic cardiomyopathy
* Most common of the cat * There’s higher incidence in males, especially of the Persian breed * Believed to be an inherited disorder in most cases * Dogs, it’s less frequent but also more in males, like in the GSD * Left ventricular concentric hypertrophy and interventricular septal thickness. Inner diameter of the left chamber is reduced, with impaired diastolic filling and higher than normal blood volume in the left atrium causing atrial dilation and increased pulmonary pressure * Stagnation of blood in the left atrium predisposes the formation of thrombus of the caudal abdominal aorta, causing paresis of the hind leg
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DCM<
* Most common cause of congestive heart failure in boxers, Dobermans, pinshcers, danes… * More often in middle ages males than females, even in cats * Causes reduced contractility and impaired systolic function with consequent ventricular congestion and atrial and ventricular dilation * Hearts ability to pump blood is diminished because the left ventricle is large and weak * Various degrees and forms of myocardial degeneration occur
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restrictive cardiomyopathy
* Rarely occurs, but happens in male cats * There’s two main endocardial lesions that disrupt ventricular filling: o Severe focal or diffuse endocardial fibrosis causing adhesion of the papillary muscles’, thickening and shortening of the mitral leaflets and fusion of the chordae tendinea o Occasionally there’s adhesion of the entire endocardium and significantly diminished ventricular cavity * Endocardium is extremely thickened by the presence of hyaline and fibrous and granulation tissue * In myocardium, there’s frequently detected hypertrophy of the muscle cells and interstitial fibroplasia with disorganisation of the cardiac muscle cells
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L heart failure
* Occurs when the output of the LV is less than the total volume of blood received from the right side of the heart from pulmonary circulation * As a result the pulmonary circuit becomes congested with blood that cannot be moved forward, and systemic blood pressure falls Symptoms: * Edema of the lungs and pleural effusion due to elevated hydrostatic pressure in the blood vessels of the lungs * Cough due to pressure of the enlarged left atrium to the left bronchus leading to the stimulation of cough receptors and lung edema * Tachypnoea and dyspnoea: reduced elasticity and reduction of ventilated parts of parenchyma leading to decreased oxygen saturation * Syncope: loss of consciousness caused by lack of blood or oxygen to the brain * General weakness and exercise intolerance because of reduced perfusion and tissue oxygenation and reductio of muscle mass * Compensatory tachycardia * Pallor or cyanosis * Drop In blood pressure
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R heart failure
* Occurs when output of RV is less than the input from the systemic venous circuit * Result, the systemic circuit becomes congested with blood and output of blood to the lungs decreases Symptoms: * Generalised edema due to increased venous hydrostatic pressure  cardiac edema * Passive hepatic congestion resulting in atrophy, degeneration, necrosis and fibrosis of polygonal liver cells  cardiac cirrhosis * Ascites due to elevated pressure in the portal vein and increased permeability of the capillary endothelium * Hydrothorax due to increased venous hydrostatic pressure along with increased capillary endothelial permeability * Dilation of the jugular vein
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myocardial infarction
* irreversible necrosis of heart muscle secondary to prolonged ischemia which occurs when a portion of the heart is deprived of oxygen due to blockage of the coronary artery * main pathological processes leading to the changes of electrical and mechanical functions is reduced oxygen deliver to myocardium and lack of oxygen leads to the complex metabolic and adaptation processes resulting in: o changes of intra and extra cellular homeostasis of ions (K, Na, Ca, Mg) o accumulation of anaerobic metabolic end products, mainly lactic acid o reduced production of energy o increased production of ROS o activation of local autonomic reflexes o increased release of neurotransmitters
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zones of damage in myocardial infarction
* 1. Zone of infarction o Area of necrosis, it’s irreversible but can be stopped from increasing in size * 2. Zone of injury o Still some recovery possible, access to blood and possibility to be viable * 3. Zone of ischemia o Full recovery is possible
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consequence of myocardial infarction
* Metabolic (anaerobic metabolism leads to lactic acid, hypoenergosis and pain) * Mechanical (loss of contractile muscle mass, decreased contractility, cardiogenic shock) * Electrophysiological (blocks, ectopic centres, bradyarrhythmia, tachyarrhythmia, ventricular fibrillation
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vomiting
* Reflexive, forceful expansion of content * Pig, dog and cat = easily, herbivores = rarely * Horses don’t vomit = underdeveloped and non-sensitive vom centre, powerful sphincter and diagonal oesophagus * Direct stimulation = neoplasm, inflammation, hypoxia * Indirect stimulation = pain, stress * Consequence: tooth damage, stomach rupture, malnutrition, hypovolemia, dehydration
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GDV
* Sudden excessive expansion of stomach due to impaired digestion * Breed, genetics, stress, activity after meal * Rotation 90-360o * Consequence = cardio, renal and GI problems * Can result in endotoxemic shock Mechanism: * 1. Increased quantity of gas and pressure * 2. Mucous ischemia (or lead to gastric tachyarrhythmia) * 3. Edema, haemorrhage, infarct and ulcer Phases * 1. Accumulation of gas in stomach, light discomfort, restless, salivation increased, trying to vomit and stomach bloated * 2. Decreased blood flow, mucosa damaged, development of hypovolemic shock, restless, whining, panting, legs apart, lowered head and dark red mucous * 3. Necrosis of stomach, spleen etc. Endotoxic shock, heart failure, death, can’t get up, white/blue mm
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dirrahoea
* Increased volume/frequency of stool Secretory * Constant secretion of water and electrolytes into lumen * Causes: hormones, drugs * Electrolyte deficiency * Doesn’t stop by fasting * E.coli.. prolonged opening of chloride ions * Secretion exceeds absorption Osmotic * Indigestion problem * Nutrients reach lumen and act osmotically active substance  cause  osmotic gradient  influx of water into lumen * Malabsorption due to pancreatic insufficiency
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hypersecretion of gastric juice
* Increased gastric juice secretion * 1. Increased conc of gastrin = gastritis, decreased catabolism of gastrin/hypertrophy and tumour of G cells * 2. Increased conc of corticosteroid = acute/chronic stress * 3. Histamine = Mastocytoma Consequence: * Peptic ulceration, deposition of bile salts, diarrhoea, steatorrhea
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hyposecretion of gastric juice
* Decreased secretion * Chronic gastritis * Diffuse atrophy of mucosa Consequence * Decreased HCl secretion, helicobacter and insuff food production
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intestinal motility disorder
Hypermotility = rough, rotten, mouldy, toxic substance, decreased food utility and absorption Hypomotility = concentrate feed, constipation, increased water absorption Intestinal spasm = inappropriate diet Intestinal atony = complete loss, distension of intestine and final stage of ileus
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IBD
* Unknown aetiology * No sex predisposition, but breed * GALT, genetic, biochem, ischemic disorder * Signs: chronic vomiting and diarrhoea, edema, ascites and anorexia * Differential diagnosis = pancreatitis, tumour, parasitic, kidney and liver failure
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gastric ulcer
= necrosis of mucosa 1. Mucosal barrier injury 2. Back diffusion of luminal acid into mucosa 3. Degranulation of mast cells releasing histamine 4. Increased secretion of pepsin and HCl 5. Mucosal erosion and damage of BV 6. Ulcer Cause: Drug, helicobacter, stress (ACTH + adrenaline), neoplasm Signs: Anaemia, weakens, weight loss, vomiting
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gastritis
* Inflammation of gastric mucosa * Irritant in food, allergies, drugs, poisons, virus Acute * Protective mucosal layer is altered, mucosal reddening, edema, superficial surface erosion * Leads to: increased motility, pain and vomit Chronic * Progressive thinning of mucosa and degeneration * Leads to superficial/atrophic gastritis
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lleus
* Intestinal obstruction * 1. Function  spastic (Pb/insecitide poisoning), paralysis * 2. Mechanical o Obstructive = closing from side (foreign body) o Compressive = closing from outside (tumour/abscess) o Strangulation = torsio intestine, invag Consequence: * Retention of feed, overgrowth of bacteria, intestinal distension and hypovolemic shock
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pancreatitis
* Acute = activation of digestive enzymes * Trypsin = activation of other enzymes * Elastase = degrades elastin * Lipase = fatty necrosis
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pancreatic insufficiency
* Undigested protein, fat and starch * Steatorrhea * Loss of body mass * LACK OF ENZYMES
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constipation
* Faeces stretches rectum * Stimulates stretch receptors, transmits signals to spinal cord * Causes contractions and relaxing of internal anal sphincter and keeps open external sphincter * Cause = lack of fibrous tissue, neoplasm, scars * Consequence = colic, vomit, intoxication
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gastric dilation In horses
* Overeating fermentable feedstuff * Lactobacillus  large production of acidic comp and gas * Spasm of cardiac sphincter * Lactate and bacterial toxin  colic * Swelling and trembling * Rupture of stomach and diaphragm * Distension pain, haemoconc, dehydration and alkalosis  death
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DIC
* Multiple clot formation and diffuse bleeding * Cause = sepsis, neoplasm, snake venom toxicities * 2 pathways  intrinsic and extrinsic which both activate thrombin *  fibrin  fibrinolysis * Results in ischemia  organ dysfunction  haemorrhage and haemodynamic
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cardiogenic shocks
* Occurs in conditions of sudden decline in cardiac work, producing insufficient arteriovenous pressure gradient * Alterations in myocardium, cardiac valves, pericardium and big blood vessels * Due to insufficient production of pressure arteriovenous gradient in cardiogenic shock adaptive mechanism are less efficient, accelerating towards MODs * Type of shock is by sudden drop of minute volume and increased venal pressure * Myocardial infarction, pulmonary embolism, trauma, heart tamponade can cause it
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distrivbutibe shock
* Irregular vascular adaption to the containing volume, causing arteriovenous pressure, gradient loss, despite normal cardiac function and maintained blood volume * Neurogenic, septic and anaphylactic shock are included * Sepsis – bacterial sepsis releases endotoxins, stimulating NO production * Anaphylaxis – immunocomplex formation causes degranulation of mast cells and basophils, released vasoactive substances systematically decrease BV tone leading to loss of arteriovenal pressure gradient * Neuropathogenic – consequence of vasomotor centre dysfunction during trauma, meningitis, intoxication or peripheral nerve disease, causes tone loss
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hypvolemic shock
* Sudden drop in circulating blood volume which exceeds 35% when venal pressure is below normal * Caused by external or internal bleeding, loss of plasma or water and electrolytes from extracellular space * External bleeding – trauma, peptic ulcer, etc * Internal bleeding – haemothorax, hemoperitoneum, etc * Plasma is lost during severe skin burns, peritonitis, ascites and hydrothorax * Water and electrolytes are lost during dehydration due to diarrhoea, vomiting, polyuria, endocrine loss of sodium and due to increased water perspiration during severe skin burns