Hepatic lipidosis/ketosis/farm Flashcards
Define negative energy balance with reference to cows?
NEB: catch all term for all conditions talked about today. We mean drop in glucose supply to cows and if mild effect get subclinical ketosis predisposes to the above discussed syndromes. Or severe where we see clinical disease.
Ketosis in cattle is not the same as?
acidosis (SARA or Acute) in cattle
Why are cows at risk of ketosis?
Long lactation
High BCS
When are cows at risk of ketosis?
Type 2
Type 2 ketosis: early lactation where lactation rockets and food intake does not.
Cant keep food intakes up to match the lactation yield spike.
When are cows at risk of ketosis?
Type 1
Milk yield gets so high we cannot provide enough
What are the differential diagnoses of ketosis?
- LDA
- Metritis
- Mastitis
Compare and contrast normal physiology and type 1 and 2 ketosis?
Normal physiology
- Some mobilisation of body fat to produce NEFAs
- NEFAs oxidised in liver using glucose from propionate and gluconeogenesis
Type 1 ketosis (Underfeeding, peak lactation)
- Reduced supply of propionate and therefore glucose
- Incomplete oxidation of NEFAs in liver leads to ketone body production
Type 2 ketosis (Hepatic lipidosis, early lactation)
- Excessive mobilisation of fat, increased NEFAs
- Incomplete oxidation of NEFA (ketones) and excessive fat accumulation in liver
- Reduced gluconeogenesis and liver function
What are the clinical signs of hepatic lipidosis and ketosis?
What is nervous ketosis and what are it’s signs?
Unusual complication
Central nervous system signs
Caused by:
- hypoglycaemia?
- Ketones?
- Other circulating chemicals?
Can be aggressive, “furious licking”
What are the diagnostic tests for ketosis and hepatic lipidosis?
Ketosis:
- Blood (cow side ketone meter or lab)
- Urine (Ketone dipstick)
- Milk (Rothera’s reagent) White powder you shake up with the milk and goes purple if ketones present.
Hepatic lipidosis:
- Look for ketones as with ketosis
- Blood NEFA
- Look for evidence of liver damage
- Liver enzymes (AST, GGT)
- Assess fat in liver
- Biopsy
- Necropsy
Define Type 1 ketosis?
- Energy intake < energy output
- “Type I” ketosis
-
Peak lactation
- Highest energy demand
- Cause and effects both normally around 20-60 DIM (days in milk, i.e. days post –calving)
- Feed lactating cows more
Define type 2 ketosis?
- Fat infiltration of liver
- “Type II” ketosis
- Not just fat cows!
- Around calving
- Diet/intake in late dry period critical
- Effects normally seen <20 DIM
- Look at how we are feeding dry cows
- Type II ketosis still not fully understood, but becoming the most important form – under- OR over-supply of energy in dry period can be important (under- as mobilising energy before calving; over- as can start to lay down fat in liver)
How can ketosis be treated?
How can ketosis occur in other species and how does it present?
Sheep
Pregnancy Toxaemia (Twin lamb disease) Does occur in beef cattle as well. This occurs before lambing/calving.
- Energy demands of late pregnancy exceed supply
- Clinically indistinguishable from hypoCa (milk fever)
- Often one will precipitate the other
- Off feed, dull and depressed, nervous signs (blindness), death
- Sporadic cases often caused by underlying disease (teeth/lameness)
- Outbreaks often triggered by change in management especially diet (reduced DMI)
- Pregnancy ketosis
- Can also occur in beef cattle
- Usually occurs before lambing
Discuss south american camelids and ketosis?
- Is it like a horse or a cow?
- Ketosis like a cow: horses don’t really get ketosis
- Hyperlipaemia like a horse: don’t usually get hepatic lipidosis like a cow
- Hepatic lipidosis can occur in extreme cases
- Usually fatal
- Always hyperglycaemic
- Or even a sheep?
- Pregnancy toxaemia does occur
- Measure ketones and blood TGs
