Food makes the difference in these twin rats : the following charts show the importance of some of the better known nutrients essential for human health
Nutrition chart, no. 2
United States. Bureau of Human Nutrition and Home Economics.
Washington, D.C, Bureau of Human Nutrition and Home Economics, U.S. Department of Agriculture, 1946
"U.S. Government Printing Office: 1946--713103."
Show pictures of twin white rats. The first rat ate a poor diet-- the bones show lacking calcium and vitamins. The second rat ate a good diet-- the bones are strong and well-formed.
Animal models in research
Rats as laboratory animals
Graphic no. 930
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