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The important flea—control ingredient in brewer's yeast is thiamine (vitamin B,). A level of one milligram (1 mg) of thiamine daily for each five pounds of your pet's body weight is ideal. For an average-size cat, this would translate to one teaspoon of brewer's yeast; for a large dog, you might administer one tablespoon of brewer's yeast supplemented with a B-complex vitamin pill. Brewer's yeast can also be dusted on externally as a flea powder. (If your pet licks some off, there's no harm done.) |