Brisket oedema

Question 1

what does oedema mean

Answer 1

reduced venous return
loss of protein
leaky capillaries

Question 2

List 9 differentials for oedema in cattle

Answer 2

High altitude disease
Malignant oedema
Liver fluke
Johnes disease
PGE
Other clostridial disease - e.g. struck
heart disease
reduced udder oedema- udder oedema
non-parasitic liver disease

Question 3

where is high altitude disease seen

Answer 3

Seen above 5,000ft altitude
Not in UK

Question 4

describe the pathogenesis of high altitude disease

Answer 4

Low oxygen saturation in the air
Pulmonary hypertension- increase hydrostatic tissue
–> Oedema in ventral tissues of chest and abdomen (ascites)

Question 5

Describe how to treat high altitude disease

Answer 5

move to lower altitude area- but slowly
diuretics
appetite stimulants (B vitamins)
thoracocentesis

Question 6

Describe how to prevent high altitude disease

Answer 6

breed for more resistant stock- don’t breen from affect animals

Question 7

what causes malignant oedema

Answer 7

Clostridium (different types)
often introduced by injection or some other deep wound

Question 8

What are the clinical signs of malignant oedema

Answer 8

Rapid multiplication deep in tissues so clinical signs in <48hrs
anorexia
depression
fever
death
may have local swelling

Question 9

what do we see on PM with malignant oedema

Answer 9

Affected muscles are dry and friable
red/black
emphysematous
Pericardium similarly affected

Question 10

Describe how to prevent malignant oedema

Answer 10

clostridial vaccines
not that expensive

Question 11

Describe how to treat malignant oedema

Answer 11

straight penicillin - needs to be for a long time
there are some surgical approaches

Question 12

Describe the aetiology of udder oedema

Answer 12

unclear
correlation with reduced dry matter intake- poss transient liver dysfunction
occurs before calving

Question 13

Describe how to prevent udder oedema

Answer 13

Diet during the dry period is most effective form of prevention

Question 14

describe how to treat udder oedema

Answer 14

Treatment may be split into nursing care and medication
Massage and hot compresses to stimulate circulation
Diuretics- if very severe - needs to be given IV
corticosteroids once calved- if inflammation very severe

Question 15

List 8 non-parasitic causes to liver disease

Answer 15

copper toxicity
neoplasia
liver abcess
hepatic necrosis
cholecystitis
chirrosis
tuberculosis
fatty liver syndrome

Question 16

what is the most common cause of hepatic necrosis in cattle

Answer 16

Fusobacterium invasion (foot-rot)
is the end stage

Question 17

what is seen with copper toxicity

Answer 17

jaundice- sclera and skin
urine- black
anorexic
depressed
D+
abdominal pain
weakness found dead

Question 18

what is seen on PM with copper toxicity

Answer 18

liver bronzed colour
kidneys - gun-metal appearance

Question 19

when do chronic copper toxicity occur

Answer 19

slow build up
Only ‘spills over’ to hypercupraemia when the storage capacity of the liver is exceeded
Will then present as acute toxicity

Question 20

when is acute copper toxicity seen

Answer 20

Acute copper toxicity is seen after inadvertent over-administration
Usually found recumbent or dead

Question 21

what is cirrhosis

Answer 21

basically chronic effects of subacute liver fluke infestation

Question 22

when do we see signs of cirrhosis

Answer 22

in early lactation when metabolic demands highest

Question 23

what do we tend to see with cirrhosis

Answer 23

constipation
Can also see other clinical syndromes associated with the damage caused by the fluke including endocarditis, salmonellosis

Question 24

What is the toxin in ragwort

Answer 24

Pyrrolizidine alkaloids

Question 25

how does ragwort poisoning occur

Answer 25

Usually cattle are not attracted to graze on it, but this should not be counted upon
Major problem if gathered up with hay

Question 26

describe the pathogenesis of ragwort poisoning

Answer 26

Direct hepatocellular damage by the alkaloids
slow, chronic ingestion is common
ACUTE poisoning rare

Question 27

describe the clinical signs of ragwort poisoning

Answer 27

weight loss
mild to moderate jaundice
photosensitisation
diarrhoea and low grade colic
Possible hepatic encephalopathy as ammonia levels rise around the brain

Question 28

what do we see with hepatic encephalopathy

Answer 28

head pressing
stupor - crazy behaviour
blindness
staggering

Question 29

Describe how to prevent ragwort poisoning

Answer 29

pull plants before they flower
do not make hay from affected fields
Sheep can be less susceptible, so may even be able to tolerate ragwort at pasture in low doses

Question 30

describe how to treat ragwort poisoning

Answer 30

adjust diet
treatment often unrewarding - because chronic and they have overcome their hepatic threshold

Question 31

Describe the pathogenesis of liver abscess in cattle

Answer 31

damage to rumen through grain overload (acidosis)
Inflammation of rumen lining —> bacteria go through rumen wall and into blood stream–> go to liver

Question 32

List some possible complications of liver abscess

Answer 32

Rupture into the abdominal cavity causing massive peritonitis
Rupture into a major vessel causing major haemorrhage, shock and sudden death
Vena cava thrombosis

But all depends on the abscess - may not see any signs of them

Question 33

describe how to treat liver abscess

Answer 33

unrewarding

Question 34

describe how to prevent liver abscesses

Answer 34

avoid acidotic ruminal conditions- feed enough roughage, do not over-feed grain