*The absence or presence of naturally-occurring phytoestrogens (isoflavones) and other natural food chemical components could be an advantage or a disadvantage, depending upon the experimental objective.
There are five basic types of diet formulas for laboratory animals:
Grain-Based Diets, such as those made by our affiliate company Purina LabDiet®. These diets are comprised mostly of natural unprocessed “multi-nutrient” ingredients, primarily cereals/grains, in which each ingredient may provide many different nutrients, with vitamins and minerals added as necessary to provide wholesome comprehensive nutrition. These diets are typically produced in batches of at least 2 tons (≈1820 kg) and usually available from stock. (Not a custom diet.)
“Direct-Add” Grain-Based Diets, in which we start with a standard grain-based Purina LabDiet® feed and mix in other nutrients. (We can also add medications and/or test compounds.)
Custom Modified Grain-Based Diets (“scratch mixes”, i.e. made “from scratch”). For these diets, we start with a standard Purina LabDiet® formula, but we modify that formula and produce unique custom diets with the scores of different ingredients each individually mixed in. We can produce as little as 5 kg of such a diet.
Purified Ingredient Diets also known as “synthetic diets”, “semi-purified” diets, and “open source” diets.
Hybrid Diets, a combination of multi-nutrient grain-type ingredients and mono-nutrient “purified” ingredients.
There are also different forms of diets: meal (powder), pellets (1/2”, 3/8”, 3/16” diameter), tablets (5 milligram to 5 gram), liquid mixes, and gels.