Control Diet Formulas
Report, Repeat and Revise
When choosing a control diet, one should ask three questions: Can I report it (can I l others exactly what my animals were fed)? Can I repeat it (is there diet variability and will I be able to get the same results next year)? Can I revise it (as my hypotheses change, can I easily change the dietary components while keeping it otherwise matched to previous diets)? The answer should be “yes” to all three. Additionally the formula should be matched to that of the experimental diet.
OpenSource Diets
Open source diets are simple to report . For example, a paper may state that “rats were fed the AIN-76A diet for the entire study”. The list of ingredients and their quantities can be easily and precisely described. Hence, researchers world wide will be able to duplicate the diet should they want to, or compare it to the diet they are using. And, since there is very little variation between batches of purified ingredients, the AIN-76A diet made today will be the same as the AIN-76A diet made a year from now. This repeatability of OpenSource diets over time provides advantages over chows, either when using a special formulation (such as one low in thiamin for example) or when using the diet for maintenance during a toxicological study, when variation in data over time may make interpreting the toxicity of the compound difficult.
It is in diet modifications where OpenSource diets most clearly illustrate their advantage over chow diets. For example, diets with high levels of sucrose (and no corn starch) have been formulated and used to study the development of insulin resistance. The fat source can be changed from coconut oil, to olive oil to safflower oil, to study the effects of changing the fat type from primarily saturated, to monounsaturated to polyunsaturated fatty acids, respectively. As mentioned earlier, individual or multiple vitamins and minerals can be removed to study their deficiencies and to define requirements. OpenSource Diets are simple to revise.
Contact one of our nutrition scientists to discuss what control diet would work best for your particular study.