Excessive intake of polyunsaturated fatty acids

Question 1

What are the major roles of fat and fatty acids

Answer 1

Fat and fatty acids have four major physiologic roles:
- as a concentrated source of energy for storage and utilization
- as structural components of cell membranes
- as lubricants
- as important signaling molecules (i.e., eicosanoids, cholesterol-derived hormones)

Question 2

Explain why cats are unique in fatty acids metabolism

Answer 2

Cats are unique in that they have low delta6 desaturase activity

Question 3

What is the clinical condition associated with excess PUFAs

Answer 3

Steatitis, a painful inflammatory condition of adipose tissue, may result from excessive intake of PUFAs or ingestion of rancid fat
- hard, painful masses can be palpated in adipose tissue of affected cats

Question 4

What is the main cause for steatitis

Answer 4

It may occur if the antioxydant activity of the food is not adequate, if the food is fed after the antioxydants are no longer effective or with homemade diets that are stored for long periods of time without added antioxydants

Question 5

Explain why vitamin E deficiency can lead to similar signs as excessive PUFAs intake

Answer 5

Ingestion of large quantities of raw fish may result in vitamin E deficiency
- fish contains PUFAs that are easily oxidized
- vitamin E is an antioxydant preventing oxidation of fatty acids in cell membranes

Signs of vitamin E deficiency include:
- pansteatitis
- decreased appetite
- hyperesthesia
- fever
- myositis