"AIN" DIETS
Diet Formula Specification Sheets:
"AIN" stands for "American Institute of Nutrition," which is now known as the America Society for Nutritional Sciences. They have published purified diet formulas that are well-accepted and respected in the scientific community as sound general nutrition for laboratory rodents.
AIN-76A. The original AIN-76 diet was soon modified by AIN-76A, which increased the vitamin K tenfold. AIN-76A has been used in research for more than 25 years.
AIN-93M & AIN-93G. In 1993, two new formulas were published to update the AIN-76A diet and to meet the new rodent nutrient requirements set forth by the National Research Council after the AIN-76A formula was published. The AIN-93G diet is designed to meet gestation, lactation, and growth requirements, and AIN-93M, containing less fat and protein, is used for maintenance of mature rodents.
These two new formulas were based on a number of alterations to the AIN-76A diet. One modification was replacing a portion of the sucrose in the AIN-76A diet with cornstarch and dextrin. The alteration was made because researchers found that high dietary concentrations of sucrose led to several complications in rodents, including hyperlipidemia, hepatic lesions (Medinsky et al., 1982), nephrocalcinosis enhancement (Bergstra et al., 1993), and increased requirement for copper (Failla et al, 1988; Fields et al., 1993). However, by making this change, the pelleting properties of the diet were disturbed, so dextrinized cornstarch, a more water-soluble starch that improves pellet quality, was also utilized in the new version (Reeves, 1997).
Other modifications made in creating the AIN-93 diets were:
1. Soybean oil was added in place of corn oil to increase the concentration of linolenic acid
2. The total phosphorus was decreased to eliminate kidney calcification concerns in female rats
3. DL-methionine was replaced by L-cystine
4. Manganese was reduced to 1/5 the original amount
5. Increased Vitamin A, Vitamin K, and B-12
6. Added molybdenum, silicon, fluoride, nickel, boron, lithium, and vanadium
Your Choice of AIN Diets. TestDiet provides both the AIN-76A and the AIN-93 diet series for our customers because some researchers prefer to use the AIN-76A diet over the AIN-93 diets. A 13 week study comparing the AIN-76A and AIN-93G diets in male and female Sprague Dawley rats found that both diets supported adequate growth. However, rats fed the AIN-76A diet exhibited increased occurrences of gastric lesions when compared with rats fed the AIN-93G diet or a grain-based diet. Additionally, rats fed the AIN-76A diet had higher serum cholesterol levels than those on the AIN-93G or grain-based diets (Lien et al., 2001).
The AIN diets are frequently used as the base formula for many different types of research. If you are interested in creating your own customized diet from one of the AIN base diets, our nutritionists will be happy to consult with you and create a diet that matches your individual needs. They can be contacted at Info@TestDiet.com, and will generally reply within 24 hours of your request. Some examples of modified AIN diets are:
The casein protein source replaced with soy, wheat gluten, lactalbumin, or egg whites.
The lard fat source replaced with cottonseed oil, coconut oil, or hydrogenated vegetable oil.
The formula adjusted to obtain all the carbohydrates from sucrose or cornstarch or fructose.
The amount of fat, carbohydrate, protein, and/or fiber adjusted.
Specific vitamins and/or minerals increased or decreased.
References:
Bergstra, A.E., A.G. Lemmens, and A.C. Beynen. 1993. Dietary fructose vs. glucose stimulates nephrocalcinosis in female rats. J. Nutr. 123:1320-1327.
Failla, M.L., U. Babu, and K.E. Seidel. 1988. Use of immunoresponsiveness to demonstrate that the dietary requirement for copper in young rats is greater with dietary fructose than dietary starch. J. Nutr. 118:487-496.
Fields, M., R.J. Ferretti, J.C. Smith, Jr., and S. Reiser. 1993. Effect of copper deficiency on metabolism and mortality in rats fed sucrose or starch diets. J. Nutr. 113:1335-1445.
Lien, E.L., F.G. Boyle, J.M. Wrenn, R.W. Perry, C.A. Thompson, and J.F. Borzelleca. 2001. Comparison of AIN-76A and AIN-93G diets: A 13-week study in rats. Food and Chem. Toxicol. 39:385-392.
Medinsky, M.A., J.A. Popp, T.E. Hamm, and J.G. Dent. 1982. Development of hepatic lesions in male Fischer-344 rats fed AIN-76A purified diet. Toxicol. Appl. Pharmacol. 62:111-120.
Reeves, P.G. 1997. Components of the AIN-93 diets as improvements in the AIN-76A diet. J. Nutr. 127:838S-841S.
See also:
Reeves, P.G., F.H. Nielsen, and G.C. Fahey, Jr. 1993. AIN-93 purified diets for laboratory rodents: Final report of the American Institute of Nutrition and ad hoc writing committee on the reformulation of the AIN-76A diet. J. Nutr. 123:1939-1951. (abstract below).
AIN-93 purified diets for laboratory rodents: final report of the American Institute of Nutrition ad hoc writing committee on the reformulation of the AIN-76A rodent diet.
[J Nutr. 1993 Nov;123 (11):1939-51]
Reeves
PG, Nielsen FH, Fahey GC Jr.
United States Department of Agriculture,
Grand Forks Human Nutrition
Research Center, ND 58202-9034.
For sixteen years, the American Institute of Nutrition Rodent Diets, AIN-76 and
AIN-76A, have been used extensively around the world. Because of numerous
nutritional and technical problems encountered with the diet during this period,
it was revised. Two new
formulations
were derived: AIN-93G for growth, pregnancy and lactation, and AIN-93M for adult
maintenance. Some major differences in the new
formulation of AIN-93G compared with AIN-76A are as follows: 7 g
soybean oil/100 g diet was substituted for 5 g corn oil/100 g diet to increase
the amount of linolenic acid; cornstarch was substituted for sucrose; the amount
of phosphorus was reduced to help eliminate the problem of kidney calcification
in female rats; L-cystine was substituted for DL-methionine as the amino acid
supplement for casein, known to be deficient in the sulfur amino acids;
manganese concentration was lowered to one-fifth the amount in the old diet; the
amounts of vitamin E, vitamin K and vitamin B-12 were increased; and molybdenum,
silicon, fluoride, nickel, boron, lithium and vanadium were added to the mineral
mix. For the AIN-93M maintenance diet, the amount of fat was lowered to 40 g/kg
diet from 70 g/kg diet, and the amount of casein to 140 g/kg from 200 g/kg in
the AIN-93G diet. Because of a better balance of essential nutrients, the AIN-93
diets may prove to be a better choice than AIN-76A for long-term as well as
short-term studies with laboratory rodents.
