Comparing Purified Diets to Grain-Based

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 not 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 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.