hyperlipaemia

• Negative energy balance (the mobilisation of fat as the source of energy) occurs due to hyperlipaemia which then causes a variety of concerns. Causes can be split into two groups…

  • Physiological causes
  • Decreased intake (due to dental disease etc)
  • Increased requirements
  • This includes pregnancy and lactation.
  • Pathological causes
  • Sepsis/SIRS
  • Azotaemia
  • This commonly occurs in hypovolaemic patients (common pre-renal cause of azotaemia too).
• pregnancy and lactation have high energy requirements but they do not always manage to eat enough. This is a concern for those who are obese as they are at a higher risk of negative energy balance and consequently hyperlipaemia.
• In endotoxemia, the release of toxins are absorbed and released into the circulation. The endotoxins trigger the release of triglycerides and slows down the activity of lipoprotein lipase (enzyme
• Hyperlipaemia is more common in mini ponies and donkeys rather than horses as these breeds are better at packing triglycerides which are then released into the blood with very low-density lipoproteins in high quantities. This then accumulates as they cannot be removed efficiently.

  • Lipoprotein lipase is the enzyme that is meant to remove them and transport them into tissue cannot keep up with production
• Diagnosis is mostly focused on triglycerides and occurs after a high suspicion e.g. an obese mini pony which isn't eating. The assessment of triglycerides uses gross appearance and the amount of triglyceride in the blood
• The reference range of triglycerides is up to 1.5 mmol/L hence…

  • 1.5-5mmol/L indicates hyperlipidaemia (the in-between stage)
  • Do not assume these cases are compensating, this shows that the process has just begun. Be proactive!
  • This stage has the best chance of correction
  • Above 5mmol/L indicates hyperlipaemia and often causes a white appearance to the serum
  • These cases are hard to return back to normal and are presented as very sick.
• state the pathology

  A) hyperlipaemia

  B) normal

  
• Liver enzymes (GGT, ALP, SDH and Bile Acids) may also be elevated. Insulin resistance can be represented by hyperglycaemia.
• treatment is focused on providing calories (which then enter the cells and reverse the negative energy balance) in any way possible. Calorie administration can be…

  • Enterally (this is more ideal)
  • Hand-grazing
  • Any feed
  • Forced (which requires a tube and passing food e.g. porridge)
  • Parenterally
  • PPN not total as you do not want to give them more fat!
  • TPN = glucose, amino acids and fat
  • Glucose infusion can be used if you cannot provide true PPN and can be helpful
• You also need to consider treatment of the primary condition e.g., pain relief or antibiotics if there is sepsis.

  • Hyperlipaemia can occur as a consequence to a primary disease but it is the hyperlipaemia that may kill the animal rather than the original disease. Hence hyperlipaemia can be the main problem
• A pony mare with a body condition score 5/5 has a foal at foot and the owner is concerned as the mare has stopped eating over the past couple of days. She is also not drinking much and is dull. You do some preliminary investigations and find that this patient has a plasma triglyceride (TG) concentration of 14.4 mmol/L, PCV is 46% and TPP is 80g/L and blood lactate concentration is 3.4mmol/L. Does this patient suffer from equine hyperlipaemia? Why has this mare developed this condition?

  Yes, likely due to the high energy requirements from pregnancy and lactation
• A Nine-year-old 280-kg Shetland pony mare with a body condition score 5/5. She has a foal on foot (3-weeks-old) and the owner is concerned as the mare has stopped eating over the past couple of days and now is also not drinking much and is dull. You do some preliminary investigations and find that this patient has a plasma triglyceride (TG) concentration of 14.4 mmol/L, PCV is 46% and TPP is 80g/L and blood lactate concentration is 3.4mmol/L. Why are PCV/TPP/ lactate elevated?

  she is dehydrated which can occur secondary to hyperlipidemia