metabolic Flashcards
CA41-44
what percent of magnesium is in the skeleton (unavailable)
60-70%
what percent of magnesium is in the soft tissues?
30-40%
what percent of magnesium is in extracellular fluid (readily available)
1%
what is the biggest output of magnesium in a cow
milk production (lactation)
where is dietary magnesium absorbed in cattle?
rumen and omasum
name 3 main clinical signs of acute hypomagnesaemia in cattle
- sudden death
- apprehensive, hyperaesthesia
- lateral recumbency, convulsions
what is the % mortality of acute hypomagnesaemia in cattle?
30% mortality
name 3 clinical signs of subclinical/chronic hypomagnesaemia in cattle
- depression in milk yield
- depression in dry matter intake
- herd irritability / nervousness
what must the plasma magnesium be below in order to diagnose hypomagnesaemia in cattle
below 0.8mmol/L
what will plasma magnesium usually be below in acute cases of hypomagnesaemia in cattle?
below 0.4mmol/L
what 2 other metabolic values will be abnormal in blood with acute hypomagnesaemia in cattle?
- hypocalcaemia
- hyperkalaemia
what can be used to control convulsions in cattle with acute hypomagnesaemia in the EU/UK
xylazine
(pentobarbitone and acepromazine not in EU)
name 2 treatment options for cattle with acute hypomagnesaemia (both injections)
- 400mL of 40% calcium borogluconate with added magnesium IV
- 400mL of 25% magnesium sulphate SC
what is the daily requirement of magnesium for a cow giving 25 L of milk?
5g
(intake will depend on absorption!)
how much dietary magnesium is absorbed in the gut by cattle?
10-35%
what is the target value of dietary magnesium to be fed to a cow per day
30g
name 4 options/methods for supplementing magnesium for cows
- medicated water
- mineral supplements in food
- dusting of pasture
- intra-ruminal boluses
name the 4-part definition of downer cow
- cow has been recumbent for over 24h
- no specific cause for recumbency
- cow is in sternal recumbency
- usually related to calving
name 4 metabolic causes of downer cow
- hypocalcaemia
- hypomagnesaemia
- untreated ketosis
- fat cow syndrome
name 4 toxaemia causes of downer cow
- metritis
- salmonella
- peritonitis
- acute coliform mastitis
name 4 neurological causes of downer cow
- obturator paralysis
- sciatic damage
- peroneal paralysis
- tibial paralysis
(caused by dystocia)
name 3 common secondary complications of downer cow
- nerve damage
- compartment syndrome
- skeletal damage
what two values can be measured to assess muscle damage in a case of downer cow
- CK (elevated for 1-2d)
- AST (elevated for 1-2wks)
what percent of downer cows will rise in 4-7 days
50%
prognosis for downer cow is poor after how many days?
10 days
is a downer cow eligible for emergency slaughter outside the slaughterhouse for human consumption?
NO
name the metabolic disease in cattle
elevated ketone bodies in blood stream (acetone, acetoacetone, betahydroxybutyrate)
hyperketonaemia
(ketosis)
name the 3 ketone bodies produced by metabolic pathways
- acetoacetate
- beta-hydroxybutyrate (BHB)
- acetone
when does ketosis often occur in cattle
in early lactation
name 3 subclinical signs of ketosis in cattle
- loss of body condition
- depressed milk yield
- reduced fertility and milk protein long-term
this common condition in cattle can be both an underlying cause or a consequence of ketosis
LDA
name the form of ketosis based on clinical signs
decreased milk yield;
weight loss;
dark firm waxy faeces;
loss of appetite;
sweet ketone smell on breath
wasting form
name the form of ketosis based on clinical signs
excessive salivation;
abnormal chewing;
licking of any available object;
incoordination, circling;
head pressing, apparent blindness;
signs intermittent
nervous form
(hypoglycaemic encephalopathy)
name 3 clinical biochemistry signs of ketosis
- lowered blood glucose levels
- elevated NEFA (mobilisation of body fat)
- elevated BHB (ketone body formation)
what cowside test can be done on the milk to help diagnose ketosis
Rothera’s test
what are the 2 main treatments for ketosis
- oral admin of glucose precursors
- vitamin B12 supplementation
this is a blood metabolite that indicates degree of fatty liver
NEFA
when does fatty liver often develop in cattle?
before and during parturition
what is the highest risk factor for fatty liver disease in cattle?
over conditioned cows
what is the most important way to prevent subclinical ketosis in cattle?
good dry cow management
(correct BCS, transitional cow diet)
this is an ionophore antimicrobial that alters microbial fermentation in the rumen to favour proprionate production to improve FCE and energy balance;
used to prevent subclinical ketosis
monensin
name the metabolic disease of sheep
energy deficiency due to increased demands at end of pregnancy;
rapid growth of foetus(s) increases demand for glucose
pregnancy toxaemia
what is the treatment for pregnancy toxaemia in sheep?
glucose
what is the daily dietary requirement of calcium for a pregnant cow?
45 g/day
what is the daily dietary requirement of calcium for a lactating cow producing 25 L of milk
65 g/day
what is the daily dietary requirement of calcium for a lactating cow producing 40 L of milk?
90 g/day
what level of calcium in the blood would be diagnostic for milk fever?
below 1.5 mmol/L
what is the treatment for milk fever in a cow?
IV calcium borogluconate (400mL) SLOWLY
do you want a positive or negative DCAB diet to prevent milk fever in cattle?
negative
when do you want to feed a full DCAB diet to cows in order to prevent milk fever?
2-3 weeks prior to calving
what does a DCAB diet do the pH of blood?
acidifies
name 2 clinical signs of ovine hypocalcaemia
- muscle paralysis
- incr resp rate and reflux of rumen contents
