Back to the knowledge base

Biotin (Vitamin B7 / Vitamin H) in dog and cat diets

A short guide to the role of Biotin (Vitamin B7 / Vitamin H) in dog and cat nutrition.

Biotin (Vitamin B7 / Vitamin H)

It belongs to the water-soluble vitamins and is sometimes called the "beauty vitamin" — it is crucial for the health of skin, coat and claws, and as a cofactor of four carboxylases it participates in the metabolism of fats, carbohydrates and amino acids [6]. Healthy gut bacteria can produce it on their own, although in the cat intestinal synthesis is less efficient than in the dog [1]. The NRC sets no requirement for dogs; for cats it indicates AI = 18.75 µg/1000 kcal ME.

Where it's found: Brewer's yeast, raw egg yolks, liver, kidneys, muscle meat and fish.

Deficiency: It manifests as a dull, brittle coat, flaking skin and fragile, cracking claws [2]. In practice it is rare — it results from prolonged antibiotic therapy (which destroys the gut flora) or from feeding large amounts of raw egg white [7]. Egg white contains avidin — a glycoprotein that permanently binds biotin and blocks its absorption. That's why you should feed the egg whole: the yolk is so rich in biotin that it more than covers whatever the white's avidin binds. Cooking deactivates avidin and likewise eliminates the problem [3].

Excess: Because it is a water-soluble vitamin, any excess resulting from a natural diet is efficiently excreted in the urine [4].

Sources

  1. National Research Council (2006). Nutrient Requirements of Dogs and Cats. National Academies Press. https://nap.nationalacademies.org/catalog/10668/nutrient-requirements-of-dogs-and-cats
  2. Frigg M, Schulze J, Volker L (1989). Clinical study on the effect of biotin on skin conditions in dogs. Schweizer Archiv für Tierheilkunde 131(10):621-5. https://pubmed.ncbi.nlm.nih.gov/2602924/
  3. Beynen AC (2023). Biotin for dogs. https://www.researchgate.net/publication/370875562_Biotin_for_dogs
  4. National Research Council (1987). Vitamin Tolerance of Animals — Chapter 12: Biotin. https://nap.nationalacademies.org/read/949/chapter/14
  5. Vadlapudi AD et al. (2012). Sodium Dependent Multivitamin Transporter (SMVT): A Potential Target for Drug Delivery. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4406285/
  6. Hand MS, Thatcher CD, Remillard RL, Roudebush P, Novotny BJ (2010). Small Animal Clinical Nutrition, 5th Edition. https://www.markmorrisinstitute.org/sacn5.html
  7. Merck Veterinary Manual (2023). Nutritional Requirements of Small Animals. https://www.merckvetmanual.com/management-and-nutrition/nutrition-small-animals/nutritional-requirements-of-small-animals