Grain-Based Diets	Purified Diets
Pros	Pros
Complex source of nutrients Closer to a "natural diet" Typically less expensive Chemicals unique to plants* (e.g., phytoestrogens) Easy to modify with one variation	Nutrients are provided from a single source Less batch-to-batch variation Can easily evaluate the effect of a single ingredient/nutrient on a response variable Easy to modify with several variations Easy to repeat precisely
Cons	Cons
Chemicals unique to plants* (e.g., phytoestrogens) Larger possible batch-to-batch variation Difficult to evaluate the effect of a single component on the response variable	Typically more expensive Do no closely resemble a natural diet*

 

*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.

The 5 Diet Formulation Type Alternatives

There are five basic types of diet formulas for laboratory animals:

Grain-Based Diets, such as those made by our affiliate company PMI 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.