40 • Alternatives to Animal Use in Research, Testing, and Education 
dictability between the model and the property 
under study increases. 
After the discrimination or predictability of a 
model, certain other criteria stand out as being 
necessary for a good biological model (1,2). A model 
should: 
• accurately reproduce the disease or lesion un- 
der study; 
• be available to multiple investigators; 
• be exportable from one laboratory to another; 
• be large enough to yield multiple samples; 
• fit into available facilities of most laboratories; 
• be capable of being handled by most investi- 
gators; 
• survive long enough to be usable; 
• exhibit the phenomenon under study with 
relative frequency; 
• be of defined genetic homogeneity or heter- 
ogeneity; 
• possess unique anatomical, physiological, or 
behavioral attributes; 
• be accompanied by readily available back- 
ground data; and 
• be amenable to investigation with available, 
sophisticated techniques. 
Depending on the type and needs of the investiga- 
tion, certain of these criteria might be more im- 
portant than others. Overall, a model with more 
of these characteristics will have higher discrimi- 
nation and stronger predictive ability. 
In research, testing, and education, a small num- 
ber of species have achieved prominence as experi- 
mental tools because they have been extensively 
studied from a number of perspectives and thus 
provide well-understood paradigms that have been 
described in detail in terms of genetics, biochem- 
istry, physiology, and other aspects. These organ- 
isms include the laboratory rat, laboratory mouse, 
fruit fly, and bacterium Escherichia coli. Yet taxo- 
nomic breadth is also required in research and 
testing, since it is often impossible to predict what 
species will lend themselves particularly well to 
the study of specific problems. In biological mod- 
eling, concentration on selected species and taxo- 
nomic diversity are not mutually exclusive; both 
play a role in the establishment of a maximally use- 
ful matrix of biological knowledge (3). 
CHAPTER 2 REFERENCES 
1. Leader R.A., and Padgett, G.A., “The Genesis and Vali- 
dation of Animal Models,” Am. J. Pathol. 101:sll-sl6, 
1980. 
2. National Research Council, Mammalian Models for 
Research on Aging (Washington, DC : National Acad- 
emy Press, 1981). 
3. National Research Council, Models for Biomedical 
Research: A New Perspective (Washington, DC: Na- 
tional Academy Press, 1985). 
4. Rowan, A.N., Of Mice, Models, & Men: A Critical 
Evaluation of Animal Research (Albany, NY: State 
University of New York Press, 1984). 
5. Russell, W.M.S., and Burch, R.L., Principles of 
Humane Experimental Technique (Springfield, IL: 
Charles C. Thomas, 1959). 
