The reason is that animals are different from humans in many aspects. For example the most commonly used monkeys to test drugs are resistant to doses of paracetamol which in many cases is deadly to humans (Proconorg Headlines). In this case it is not sensible to use animals or anything for that matter that are resistant to drugs that could hurt humans. Another reason to support the stopping of animal testing is an analysis. In an analysis of over 100 mouse cell types only 50% of the DNA responsible for regulating genes in mice was matched with human DNA (Proconorg Headlines). Using a animal with only 50% of a match is not ideal. In conclusion using anything that isn't a 100% match of DNA or anything else should not be used to test drugs or products for