Species of animals selection

An issue of obvious importance in test species selection is the degree to which test results can be reliably applied to human beings. As we noted in the last chapter this is one of the principal problems in the evaluation of human risk, and we shall get back to it in the later chapters on risk assessment. For now, emphasis is on the selection of animal species and strains for their known reliability as experimental subjects. To put it in stark (but honest) terms - the animals are used as toxicity measuring devices. 

Assist in the selection of animal species that can act as a surrogate of human toxicity. 

Table 2 Factors governing the selection of animal species for dermal irritation testing...

Tantisricharoenkul G, Linde-Rosen M, Araujo P et al (2014) Anterior cmciate ligament an anatomical exploration in humans and in a selection of animal species. Knee Suig Sports Traumatol Arthrosc 22 961-971... 

Provide scientific basis for predicting human PK from in vitro metabolic rates or from animal PK Provide scientific basis for selection of animal species for toxicology studies... 

For consideration of the selection of animal species for repeated dose studies see section 3.3. The route and dosing regimen (e.g., daily versus intermittent dosing) should reflect the intended clinical use or exposure. When feasible, these studies should include toxicokinetics. 

The selection of animals is described in detail in the new guidance. For example, two species should be used, primarily rats and rabbits. Reasons should be given if other species are preferred. The minimum number of animals in each dose level is also specified, referring to the ICH notes. 

Such a dichotomy cannot be resolved in a generic manner. Although it may be advisable that chronic effect results be obtained from both a rodent and nonrodent, the selection of appropriate species for chronic toxicity tests should be based upon practical reasons and the results of previously conducted studies. In some cases, testing with a single species may provide sufficient data for assessing test chemical hazards. Strains of test animals should be well characterized for commonly found diseases and their resistance, and should be free from congenital defects. 

The morphology of animals Is so apparently different from that of man that It Is often overlooked In the Interpretation of test results or In the selection of appropriate species for testing. Comparative anatomical studies have revealed Important... 

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