Final Exam - FA Hepatobiliary Disease

Question 1

what animals don’t have gallbladders?

Answer 1

horses & camelids

Question 2

if you have an increase in unconjugated bilirubin, what does that indicate?

Answer 2

decreased hepatic function

Question 3

T/F: increased liver enzymes don’t equate to liver failure

Answer 3

true - liver failure can exist with normal enzyme levels especially if you only have cellular enzymes on chemistry

Question 4

T/F: early liver disease is easy to detect & diagnose in food animals

Answer 4

false - often inapparent to owner & vet

Question 5

what are some clinical signs of liver disease in production animals?

Answer 5

lethargy, anorexia, weight loss, ‘poor doer’

jaundice, photosensitivity, hepatic encephalopathy (abnormal mentation, vocalization, circling, head pressing), coagulopathies, & hemolysis

Question 6

what is your biggest diagnostic test for liver disease in production animals?

Answer 6

chemistry panel

Question 7

what are the benefits of using an ultrasound for suspected liver disease in production animals?

Answer 7

structural disease especially on the right - tumors or abscesses & it is non-invasive

not great for toxic/metabolic/infectious causes

Question 8

what are the benefits of a liver biopsy for liver disease in production animals?

Answer 8

definitive diagnosis & prognostic capabilities, sample of choice for most assessments, & ruminants are relatively easy/safe to biopsy

Question 9

what vaccine should you give prior to a liver biopsy in a ruminant?

Answer 9

clostridial +/- penicillin

Question 10

what are the most common agents involved in liver abscesses?

Answer 10

fusobacterium necrophorum & truepurella pyogenes

Question 11

other than the most common agents, what can be another cause of liver abscess?

Answer 11

traumatic reticuloperitonitis - especially in dairy cows

Question 12

liver abscesses are most common in what animals?

Answer 12

cattle on a high grain diet - dairy cattle, feedlot cattle, & show cattle

Question 13

what is the pathogenesis of liver abscesses in production animals on a high grain diet?

Answer 13

chronic rumen acidosis damages the rumen mucosa - bacterial translocation into portal circulation - infiltration into the liver

Question 14

what is the best antemortem diagnostic for liver abscesses?

Answer 14

ultrasound

Question 15

what is the treatment for liver abscesses in food animals?

Answer 15

prolonged antimicrobials (macrolide or penicillin) for valuable animals or cull

Question 16

how can we prevent liver abscesses?

Answer 16

gradual adaptation to diet to prevent acidosis, feed additives (tylosin), increase roughage

Question 17

what are the clinical signs of liver abscesses in production animals?

Answer 17

generally subclinical with normal lab values - may have elevated globulins from long standing inflammation

Question 18

what is a major complication associated with liver abscesses? what is the pathogenesis of it?

Answer 18

vena cava thrombosis syndrome

liver abscess erodes into vena cava & it seeds the lungs (embolic/metastatic pneumonia) - animal may present as respiratory disease

foci in pulmonary vasculature can erode through vessel walls causing hemorrhage into lumen of alveoli/smaller air passages - death

Question 19

what animals are more susceptible to flukes than cattle?

Answer 19

sheep, goats, camelids

Question 20

where do flukes thrive?

Answer 20

warm, wet conditions

Question 21

what is the intermediate host of flukes?

Answer 21

snails

Question 22

what is the most common liver fluke in this region?

Answer 22

fasciola hepatica - flukes mature & become encapsulated in the liver

Question 23

what are the clinical signs of flukes dependent on?

Answer 23

worm burden

Question 24

what are some effects of flukes on production?

Answer 24

negligible at < 10 flukes per animal

possible at 10-40 flukes per animal

probable at > 40 flukes per animal

clinical disease at > 200 flukes

Question 25

what are some clinical signs associated with fascioliasis?

Answer 25

decreased productivity, weight loss, ill-thrift, anemia, bottle jaw/edema, hypoproteinemia exacerbated by periods of nutritional stress

Question 26

what is the clinical pathology associated with liver flukes?

Answer 26

increased GGT, ALP due to biliary obstruction or changes hypoproteinemia, anemia, +/- mild eosinophilia

Question 27

how are liver flukes diagnosed?

Answer 27

fecal sediment, clinical signs, necropsy selecting 10-15 random animals from a herd is a decent diagnostic

Question 28

what is the treatment for liver flukes?

Answer 28

albendazole for adults & clorsulon for immature flukes

Question 29

how can liver flukes be prevented?

Answer 29

deworm in the fall after the infection period & optional spring deworming for heavily affected herds

Question 30

what agent causes redwater disease?

Answer 30

clostridium haemolyticum - clostridium novyi type D

Question 31

what is the pathogenesis of redwater disease?

Answer 31

liver damage (caused by fluke migration) creates anaerobic environment for clostridial spores - spores produce beta toxin causing hepatocyte necrosis, intravascular hemolysis, & damage to the endothelium systemically - hemolytic anemia leads to hemoglobinuria

Question 32

when are redwater outbreaks seen?

Answer 32

occur after flooding or otherwise seasonal following fluke migration

Question 33

what is another name for redwater?

Answer 33

bacillary hemoglobinuria

Question 34

what are the clinical signs associated with redwater?

Answer 34

sudden death most common - hemoglobinuria, icterus, weakness, ataxia, anemia

Question 35

how is redwater diagnosed?

Answer 35

necropsy - liver infarct with hyperemic zone bordering normal liver, gram stain, fluorescent antibody test, & pcr for organism

Question 36

what is the treatment & prevention of redwater?

Answer 36

treatment is unrewarding - maybe high doses of penicillin fluke prevention & vaccination for clostridium novyi type D

Question 37

what is another name for black disease?

Answer 37

infectious necrotic hepatitis

Question 38

what is the agent that causes black disease?

Answer 38

clostridium novyi type B

Question 39

what animals are most commonly affected by black disease?

Answer 39

sheep - other ruminants & horses

Question 40

what exotoxins are produced in black disease?

Answer 40

alpha & beta toxin

Question 41

what is the pathogenesis of black disease?

Answer 41

same as red water - flukes cause damage & allow for proliferation

Question 42

what are the clinical signs of black disease?

Answer 42

sudden death - may see fever, lethargy

Question 43

how is black disease diagnosed?

Answer 43

clinical signs & necropsy - skin blackened from venous congestion/capillary rupture, pale areas of coagulative hepatic necrosis need combo of history, clinical signs, necropsy findings, & pathogen isolation from liver

Question 44

what is the treatment & prevent for black disease?

Answer 44

treatment is unrewarding - vaccinate for clostridials & have good fluke control

Question 45

what plant is this? what does it cause?

Answer 45

fiddleneck (pyrrolizidine alkaloid) - photosensitization

Question 46

what are the clinical signs associated with pyrrolizidine alkaloid toxicosis?

Answer 46

delayed signs - usually in liver failure at time of presentation

Question 47

how is pyrrolizidine alkaloid toxicosis diagnosed?

Answer 47

liver biopsy & necropsy

Question 48

what 3 major changes are seen on necropsy of an animal with pyrrolizidine alkaloid toxicosis?

Answer 48

megalocytosis, bridging fibrosis, & biliary hyperplasia

Question 49

what is the toxin produced from blue-green algae?

Answer 49

cyanobacteria that produces hepatotoxic microcystins

Question 50

when is blue-green algae usually a problem?

Answer 50

warm months when water temperatures are higher & the water is stagnant

Question 51

what clinical signs are associated with blue-green algae toxicosis?

Answer 51

acute mortality event in herds - severe hepatocellular damage leading to hypovolemia & shock due to blood loss nervousness, reluctance to move, recumbency, diarrhea, & pale mucus membranes

Question 52

what may be seen on diagnostics for an animal with suspected blue green algae toxicosis?

Answer 52

increased GGT, AST, bile acids, & ALP with hypoglycemia & hyperkalemia

Question 53

what is the treatment for blue green algae toxicosis?

Answer 53

unrewarding

Question 54

what is hepatic lipidosis?

Answer 54

fat animal that abruptly experiences a negative energy balance - body mobilizes fat stores which go to the liver & overwhelm its capacity to the point of compromising function lactation - fat dairy cows gestation - fat beef heifer fat goats with pregnancy toxemia

Question 55

what are some clinical signs of hepatic lipidosis?

Answer 55

anorexia, lethargy, decreased milk production

Question 56

how is hepatic lipidosis diagnosed in production animals?

Answer 56

ultrasound, biopsy, FNA

Question 57

how do you treat hepatic lipidosis in production animals?

Answer 57

get them out of a negative energy balance - palatable foods, IV dextrose

Question 58

how is hepatic lipidosis prevented?

Answer 58

don't let animals become overconditioned prior to calving identify & treat/prevent comorbidities

Question 59

what disease causes this appearance?

Answer 59

red water disease