Thiamine deficiency in cats

When we read about recent cases of thiamine deficiency in cats fed preserved pet meats in Sydney we also found this American report about thiamine deficiency in cats fed uncooked fish and some pate type can foods.

Thiamine is essential for carbohydrate metabolism, muscle
contraction, and nerve conduction. Very little thiamine is stored in the
body and cats depend on a steady dietary
source of the vitamin. Thiamine is naturally found in many food sources
such as whole grain cereals, nuts, legumes, brewer’s yeast, but cats derive thiamine mainly from meat
products, in particular skeletal muscle, liver, heart, and
kidneys.

Improper food storage and processing, consumption of uncooked
fish that contain the enzyme thiaminase, and consumption of diets with
sulfur dioxide or sulfite meat preservatives can lead to insufficient
dietary thiamine.

After two to four weeks of a thiamine deficient diet,
cats exhibit salivation, anorexia (loss of appetite), and sometimes
vomiting. If the deficiency is not corrected, then dilated pupils,
bradycardia (slow heart rate), aggression, and progressive neurological
symptoms such as ataxia (loss of coordination), rigid head and neck
ventroflexion, twitching, loss of righting reflexes, seizures, coma, and
death will ensue. Rigid head and neck ventroflexion is the most common
clinical sign in cats presented to veterinarians.