Thiamine deficiency in dogs and cats

Abstract

Vet Med Today: Timely Topics in Nutrition 649 I past years, nutritional deficiencies were considered to be an important problem in dogs and cats. Currently, most pet owners in many countries, such as the United States and Canada, feed nutritionally balanced commercial pet foods. As a result, nutritional deficiencies have become uncommon because reputable pet food manufacturers regularly test their products to ensure that they contain adequate amounts of all nutrients. Anecdotally, most reported deficiencies currently arise from animals eating incomplete or unbalanced homemade, vegetarian, or raw meat diets. Therefore, veterinarians may not consider deficiencies as differential diagnoses in animals eating traditional commercial diets. However, thiamine (vitamin B 1 ) deficiency is of clinical concern even today. Since 2009, there have been 5 major voluntary pet food recalls involving thiaminedeficient pet foods in the United States that ultimately involved 9 brands of cat foods and at least 23 clinically affected cats. Most of these recalls were instituted in response to a report from a consumer or veterinarian after treating a cat that had clinical signs consistent with thiamine deficiency. In addition to the possibility of a deficiency in commercial pet foods, there are a variety of situations in which a deficiency may arise in dogs or cats with medical conditions. Clinical manifestations of a deficiency of thiamine are variable, and the disease is likely underreported because of the wide array of clinical signs in combination with a lack of specific clinicopathologic changes detected via laboratory analysis. Thiamine has received much attention as a vitamin deficiency that is common in ruminants, primarily as a result of rumen bacterial inactivation of the vitamin, which results in characteristic cerebrocortical necrosis and neurologic signs. Dogs and cats can also be affected by deficiency of this vitamin because of an inability to endogenously synthesize large quantities of thiamine. Therefore, both cats and dogs need to have a consistent dietary supply of thiamine. As with all B vitamins, thiamine is water soluble, stored in the body in small amounts, and subject to urinary losses. Thiamine is also particularly labile and easily destroyed by typical foodprocessing techniques. In fact, many early experiments Thiamine deficiency in dogs and cats