liver 1-3

Question 1

The liver is unusual in that it has 2 sources of blood supply: the hepatic artery (which supplies about 25% of the blood flow to the liver) and the portal vein (which supplies the remaining 75%). Which of these sources has the highest oxygen content?
a. Hepatic artery
b. Portal vein

Answer 1

a. Hepatic artery - this brings freshly oxygenated blood from a branch of the aorta

Question 2

which of these sources has the highest nutrient content?
a. Hepatic artery
b. Portal vein

Answer 2

b. Portal vein

Question 3

hepatic lobule diagram - which is the central vein, portal triad, and tube of hepatocytes?

Answer 3

The basic functional unit of the liver is the hepatic lobule, a cylindrical tube of hepatocytes surrounding a central vein. The edges of each hepatic lobule are marked by portal triads, which consist of a tiny bile duct, a venule that is a branch of the portal vein, and an arteriole that is a branch of the hepatic artery

Question 4

which out of mice and rats don’t have a gallbladder?

Answer 4

rats - don’t have a gallbladder
mice - do

Question 5

horse, rabbit, deer, alpaca, rat, cow - which ones have a gallbladder?

Answer 5

only the cow - common species (cat, dog, ruminants (sheep/cows) all do)

Question 6

bile duct system - find the:
- Common bile duct
- Duodenum
- Gallbladder
- Liver
- Pancreas
- Pancreatic duct

Answer 6

Question 7

what is liver disease?

Answer 7

Question 8

what is liver failure (hepatic insufficiency)?

Answer 8

more than 70/80 percent of liver is poked

Question 9

is it acute, chronic, or cirrhosis (end stage) liver failure?
- develops rapidly, without pre-existing liver failure
- can be treated, may return to normal
- seen with some toxicities and infectious diseases

Answer 9

acute liver failure :)

Question 10

is it acute, chronic, or cirrhosis (end stage) liver failure?
- develops slowly over months or years
- will not resolve, will progress to end stage liver failure
- common, large number of possible causes

Answer 10

chronic liver failure

Question 11

is it acute, chronic, or cirrhosis (end stage) liver failure?
- irreversible, result of progressive chronic liver disease
- results in diffuse hepatic fibrosis (small, pale, firm liver, interspersed with nodules of regenerating tissue)
- results in hepatic insufficiency and associated clinical signs/blood changes

Answer 11

cirrhosis (end stage) liver

Question 12

what does cholestasis mean?
a. inflammation of the liver parenchyma
b. inflammation of the biliary tract (mainly bile ducts)
c. inflammation of the gallbladder
d. inflammation centred on the biliary tract which extends to involve the adjacent liver tissue
e. reduced bile secretion and flow

Answer 12

e. reduced bile secretion and flow - cholestasis

Question 13

what is hepatitis?
a. inflammation of the liver parenchyma
b. inflammation of the biliary tract (mainly bile ducts)
c. inflammation of the gallbladder
d. inflammation centred on the biliary tract which extends to involve the adjacent liver tissue
e. reduced bile secretion and flow

Answer 13

a. inflammation of the liver parenchyma = hepatitis (suffix -itis means inflammation)

Question 14

what does cholangitis mean?
a. inflammation of the liver parenchyma
b. inflammation of the biliary tract (mainly bile ducts)
c. inflammation of the gallbladder
d. inflammation centred on the biliary tract which extends to involve the adjacent liver tissue
e. reduced bile secretion and flow

Answer 14

b. inflammation of the biliary tract (mainly bile ducts) = cholangitis (prefix chole- means relating to bile)

Question 15

what does cholangiohepatitis mean?
a. inflammation of the liver parenchyma
b. inflammation of the biliary tract (mainly bile ducts)
c. inflammation of the gallbladder
d. inflammation centred on the biliary tract which extends to involve the adjacent liver tissue
e. reduced bile secretion and flow

Answer 15

d. inflammation centred on the biliary tract which extends to involve the adjacent liver tissue (like cholangitis, but with liver involvement)

Question 16

what does cholecystitis mean?
a. inflammation of the liver parenchyma
b. inflammation of the biliary tract (mainly bile ducts)
c. inflammation of the gallbladder
d. inflammation centred on the biliary tract which extends to involve the adjacent liver tissue
e. reduced bile secretion and flow

Answer 16

c. inflammation of the gallbladder

Question 17

what does acute liver response to injury normally look like?

Answer 17

• degeneration or necrosis (same as other cells)
• appears paler than normal, swollen, more friable and with rounded edges instead of tapered

Question 18

what does a normal liver look like?

Answer 18

• dark red brown tissue (parenchyma) divided into lobes with well defined edges that taper to a point (not rounded)
• in species with a gallbladder, this is normally on the right

Question 19

in what species is it normal for the edges of the liver lobe to be fimbriated?

Answer 19

camelids - fucking weird things

Question 20

Hypoxic liver damage (due to a lack of oxygen) has a specific microscopic pattern that can be seen on histology. Using your knowledge of the direction of blood flow in the liver, predict which part of the hepatic lobule on the right would be most affected by hypoxia (hint: which area receives blood last?)
a. Periportal
b. Mid-zonal
c. Centrilobular
d. All would be affected equally (diffuse)

Answer 20

look at the diagram my boi

Question 21

what are the three ways the liver typically responds to chronic injury, which often occur together?

Answer 21

• regeneration
• fibrosis
• biliary hyperplasia (microscopic)

Question 22

the pale colour of this sheep liver overall is due to:
a. regeneration
b. fibrosis
c. biliary hyperplasia

Answer 22

b. fibrosis

Question 23

The nodules of brown tissue of varying sizes seen in the right image are nodules of:
a. Regeneration
b. Fibrosis
c. Biliary hyperplasia

Answer 23

a. Regeneration

Question 24

which livers are consistent with acute liver disease vs chronic liver disease?

Answer 24

acute - flossie
chronic - fencepost and fern

Question 25

which five metabolic processes is the liver very involved in?

Answer 25

1. bile and bilirubin formation/secretion 2. carbohydrate, lipid, vitamin metabolism (including glucose) 3. protein synthesis and secretion (albumin, coagulation factors) 4. detoxification (safe storage, excretion) 5. immunity

Question 26

why is bile important?

Answer 26

for fat digestion and waste toxin excretion

Question 27

true or false - milder liver disease is often clinically silent or produces non specific signs such as anorexia, weight loss, lethargy, vomiting or diarrhoea?

Answer 27

true - this is because the liver has a large functional reserve, signs only become obvious when the damage is severe enough or if there's bile drainage blockages (cholestasis). long story short, take bloods xx

Question 28

do all animals with liver disease have jaundice? a. yes b. no

Answer 28

b. no - serum bilirubin needs to be at >45-50umol/L to cause jaundice, and not all animals with liver disease have increased bilirubin lol

Question 29

advanced liver failure (generally >70-80% loss of liver function) signs - why does oedema happen?

Answer 29

the liver doesn't produce enough albumin

Question 30

advanced liver failure (generally >70-80% loss of liver function) signs - why do haemostatic defects /increased bleeding happen?

Answer 30

liver not producing enough various coagulation factors (liver also involved in vit K synthesis, also needed for some clotting factors).

Question 31

What type of anaemia would you expect to see with a coagulopathy due to liver failure? a. Pre-regenerative b. Regenerative c. Non-regenerative

Answer 31

b. Regenerative

Question 32

which tests of homeostasis would you expect to be abnormal in an animal with coagulopathy due to liver failure? a. buccal mucosal bleeding time (BMBT) b. protrombin time (PT) c. activated partial prothromboplastin time (APTT) d. platelet count

Answer 32

normal: a. buccal mucosal bleeding time (BMBT) d. platelet count abnormal: b. protrombin time (PT) c. activated partial prothromboplastin time (APTT)

Question 33

why does liver failure sometimes lead to photosensitisation in herbivores?

Answer 33

- liver is meant to excrete phytoporphyrins (plant breakdown) - too many build up in blood then skin, get activated by sunlight = crispy

Question 34

why does liver failure sometimes lead to neurological signs (eg hepatic encephalopathy?)

Answer 34

- liver is meant to convert a bunch of toxic stuff eg ammonia to non toxic versions eg urea - these toxins stay in the blood in concentrated volumes - cross BBB and damage neurons :(

Question 35

would the following be low or high with liver failure? - albumin - bilirubin - ammonia - urea - anaemia - erythrocytosis

Answer 35

- albumin: low (not enough made) - bilirubin: high (not removed) - ammonia: high (not removed) - urea: low (not made) - anaemia: high (lack of clotting factors made)

Question 36

What colour vacutainer would you use for haematology testing (a complete blood count)? a. Purple top (EDTA) b. Red top (no additive) c. Blue top (citrate) d. Green top (heparin)

Answer 36

a. Purple top (EDTA) - this is the preferred anticoagulant for haematology

Question 37

What colour vacutainer would you use for serum biochemistry testing, which includes things like enzymes, electrolytes, proteins and hormones? a. Purple top (EDTA) b. Red top (no additive) c. Blue top (citrate) d. Green top (heparin)

Answer 37

b. Red top (no additive) - because this tube has no additives, blood will clot in it, separating the clot of RBCs from the plasma

Question 38

why bother with serum analysis?

Answer 38

different organs contain different enzymes, if one is increased in the blood of a sick animal you can localise the damage or disease to the organ

Question 39

Enzymes are measured in serum based on.. a. their concentration b. their activity

Answer 39

b. their activity - to test it they add substrates to a sample and the enzyme catalyses it, which means they can measure either the product or the amount of substrate used (this is done photometrically)

Question 40

why are enzyme analysis tests done at 37 degrees?

Answer 40

enzymatic reactions are temperature dependant