Anaemia in sheep Flashcards
List 5 causes of sudden death in sheep
is anthrax until proven otherwise
clostridia
lightening
parasite- haemonchus contortus, nematodirus battus, fasciola hepatica, coccidiosis
HYpomagnesium- staggers
why do we not rely on FEC results to identify when to treat sheep for nematodirus battus
as soon as it hits 10 degrees (warm enough for them to mature and become infectious)- huge numbers are taken in and animals will die before they start to excrete eggs in faeces
Use a forecaster to predict when to worm
coccidiosis is normally a …… finding in sudden death
secondary
generally causes issues when animal is already immunosuppressed
In any anaemia: initially blood count remains ……., before we start seeing anaemia and ……. (so doing blood count at this initial stage may not be very useful)
normal
hypoproteinaemia
What is the most common parasitic cause of blood loss in sheep
Haemonchus contortus
where are Haemonchus contortus adults generally found in animal
abomasum
Describe the features of haemonchus contortus which make it good at killing animals
has short life cycle - one of the reasons animals don’t develop immunity to it
survives well at pasture
high daily egg output
no diarrhoea seen
Describe the appearance of animals with an acute infection of haemonchus contortus
animals weak
pale mucous membranes
hyperpnoea
tachycardia
still in good body condition
sudden death
why does chronic Haemonchus infections cause microcytic anaemia
chronic nature depletes iron reserves - not enough to generate appropriate levels of erythrocytes in blood stream
List 5 possible differentials for bottle jaw in sheep
heart failure- not very common in sheep
Johne’s disease
liver fluke
Haemonchus contortus
cardiac dysfunction
anything that causes hypoproteinaemia
what could you use on the farm as a temporary haemostat (stop blood)
Cobwebs
In overt blood loss would complete blood count remain normal at first
yes
when would see start seeing regeneration of RBCs after overt blood loss
a couple of days after
can you put ruminator blood through haematology machines
needs to be suitable for ruminant blood as it is sticky
what can we use instead of haematology machines to asses blood in cows
blood smears
What is the primary differential for haemolysis in sheep
a result of toxin ingestion
List 4 common toxins ingested that can cause haemolysis in sheep
Copper toxicity
sulphue toxins- onions and brassicas
nitrates and nitrites - from overfertilized land
List the signs seen with copper toxicity in sheep
anorexic
depressed
diarrhoea
abdominal pain
weakness
found dead
what is seen on PM of animal with chronic copper toxicity
jaundice- of sclera and skin
urine- black in colour
liver- bronzed
kidneys- metalic appearance
why are copper blood levels not a good indicator of chronic copper toxicity
- due to liver storage - copper levels may be normal
- it is only when liver storage capacity is exceeded that we get high blood copper levels
Which breeds are particularly prone to copper toxicity
texels and suffolks
Describe how you would treat copper toxicity
usually furtile
supportive of acute renal failure
fluid therapy blood transfusion if indicated
List the 4 possible causes of water poisoning
- Excess Na ingestion with adequate (normal) water intake
- Normal Na ingestion with inadequate water intake
- Consumption of high Na water
- Administration of hypertonic oral electrolytes
List the clinical signs seen with water toxicity
thirst
reduced mentation
hyperthermia
tachycardia
rumen stasis
diarrhoea
mucoid faeces
nasal discharge
convulsions
found dead
