Equine hyperlipaemia

Equine hyperlipaemia

1. Clinical signs

   • Depression
   • Anorexia due to high TG's
   • Ataxia
   • Diarrhoea
   • Peripheral oedema

2. Risk Factors

   • Obese
   • PPID
   • Insulin resistance
   • Ponies, miniature, obese pregnant mares
   • Easy keeper

3. Biochemistry

   • Elevated AST and GGT
   • Azotaemia
   • Elevated bile acids
   • Hypoglycaemia
   • Hypoalbuminaemia

4. Pathology

   • Liver enlarged, pale and greasy.
   • Lipaemic serum
   • Liver biopsy shows infiltration of hepatocytes with fat

5. Diagnostic plan

   • Can diagnose by appearance of blood. Will be turbid and cloudy with increased TAGS
   • >1.0mmol/L TAG is +VE

6. Pathophysiology

   • High risk, obese animal is in NEB
   • Obese animals release more fatty acids from adipose because larger amounts of stored TG and IR makes HSL more sensitive
   • Excessive fatty acids released ; NEFA concentrations rise
   • Liver overwhelmed by fatty acids - fatty acids converted to TGs and VLDLs used as 'overflow' pathway and secretes lipoprotein lipase. VLDLs accumulate in blood and cause fatty infiltration of organ

7. Treatment

   • Nutritional support v important
     • IV glucose (5% dextrose) in CRI
     • Followed by protamine zinc insulin
     • Nasogastric high energy complete feed such as barley
     • Heparin to potentiate lipoprotein lipase to hydrolyse VLDL carried TG
   • Enteral
     • If finances are limited
       • Get complete feed and calculate how much it would need if it was the primary calorie source. Begin with 25% of it and increase to 50% over 3 days - soak feed in warm water until slurry and give vianasogastric tube
       • Or dextrose powder dissolved in water and syringe
   • Parenteral
     • If finances are sufficient
     • Lipid free PPA - partial parental nutrition
       • Where 50% of calorific needs are glucose or amino acids
       • calculate 50% of its total needs and give this as PPN
       • Make sure to check glucose via urine dipstick during new protocol