Scour (Cram Set)

Question 1

Why the weak pulse in hypovolaemia?

Answer 1

Calf in shock

Less blood volume = less blood pumped around body

Question 2

How do baroreceptors respond to low blood pressure?

Answer 2

Decreased firing to medulla oblongata
Reduced vagal tone
Increased heart rate and force, peripheral vasoconstriction,
Heart increases stroke volume

Question 3

Why vaccinate cows and not calves?

Answer 3

Calves’ immune system not fully developed
Maternal antibodies may be present
Long length of time between exposure and immune response

Question 4

Types of viral infection?

Answer 4

Cytosidal ? morphological changes to cell (CPE), inhibition of protein and DNA and RNA synthesis
Persistant non?cytosidal (productive) ? no CPE, some loss of function?
Persistant non?cytosidal (non?productive) ? no effects
Transformation ? immortalised cells

Question 5

How are viruses recognised by interferons?

Answer 5

Certain viral proteins recognised e.g. flagellum, double stranded RNA, viral glycoproteins, endotoxins ? infected cell produces interferons which go to uninfected cells ? pathogen recognition receptors

Question 6

How do viruses evade IFN response?

Answer 6

Inhibit IFN?induced enzymes

Inhibit IFN?IFN receptor interaction

Question 7

Why hyperkalaemia with diarrhoea?

Answer 7

Loss of K in diarrhoea

Because of acidosis, H ions in blood, body exchanges K for H using antiporter, so K in blood to raise pH

Question 8

fluids?

Answer 8

NaCl, water, HCO3