Learn More About Custom Research Diets

Custom research diets usually fall into some general classifications, and are briefly described below.

• Purified diets use refined ingredients such as casein, sucrose, corn starch, fat, oil, and cellulose. These food grade ingredients have relatively simple chemical compositions (predominantly one nutrient classification), and this feature is important for manipulating individual nutrients for research objectives. Selected refined ingredients provide uniformity and reproducibility benefits, and also help reduce natural substances which may have biological activity.
   
• Natural ingredient diets contain the types of feedstuffs commonly associated with standard diets for laboratory animals. Ingredients such as corn, wheat, soybean meal, alfalfa meal, fish meal, and other by-products have relatively complex and variable chemical compositions. However, selected ingredients of this nature sometimes can be used for a custom research diet. See NaCl Adjusted Series for a rodent diet example. Research diets for certain species (rabbits, guinea pigs, swine, primates) may utilize some of these kinds of ingredients for various reasons.
   
• Hybrid diets contain a mixture of natural and refined ingredients. This approach might be necessary to limit specific nutrients or non-nutrient substances. The inclusion of some natural ingredients can enhance palatability of the diet, particularly for rabbits and guinea pigs.
   
• Standard diets can serve as the base to add various types of in-house ingredients. This could be an ingredient such as cholesterol, lithium, doxycycline, Uniprim, vitamin E, etc. You can choose from a variety of different standard rodent diets as the base diet.
   
• Customer supplied ingredients can be added at a prescribed amount to a purified, natural ingredient, hybrid, or standard diet.   We add a wide variety of test compounds, food components, prescription medications, herbs, and much more, to a variety of base diets. See customer supplied ingredients to learn more about this process.

Manufacturing
Most research diets diets are available in two forms, powder or pellet, with some exceptions when only powder is available. To pellet diets, deionized water is added to the mix, the mix is pelleted, and then the pellets are dried in a vacuum oven for a length of time necessary to remove the added water. Air-drying (no added heat) might also be an option that can be discussed with technical services.

Quality Assurance
Each formula is given a unique identification number and retains that identity among the thousands of formulas in our files. This assures the same formula can be used even years later. Most Teklad product codes begin with "TD" followed by a five digit number, the first two digits being the year of origin. Some older formulas begin with "CA" followed by a six digit number. All phases of diet production are controlled closely. Detailed production records and quality-control samples are maintained for every item produced. Each lot of the major protein ingredients is analyzed for a number of nutrients to verify uniformity from lot to lot.

Irradiation
Most custom research diets do not withstand autoclaving; however, we can arrange for qualified diets to be irradiated. The irradiation dose range is 2 -5 MRad, or 20-50 kGy. Nominal fees and extra time are involved.  Please contact Customer Service for details about irradiation costs and additional lead time. Vacuum packaging may be helpful in reducing irradiation-induced peroxide formation in high fat diets. Technical Services can assist you in determining if a formula is suitable for irradiation.