Invertebrates Used for Testing
Invertebrates are commonly used in animal testing although they are not safeguarded under animal testing regulations in most countries. This means that the typical stringent record keeping and statistical aspects of animal testing use do not apply to invertebrates. As such, the overall number of invertebrates that are utilised for testing purposes is not known.
Benefits of Using Invertebrates in Animal Testing
Invertebrates hold numerous benefits in comparison with vertebrates. The lack of tight regulatory requirements means that they can be used more freely and with less concern regarding records keeping. In addition, animal welfare groups are not as likely to target the use of invertebrates versus vertebrates, which means that researchers do not have to fear the threats and attacks experienced by those who test on some of the other animals used for research purposes. Invertebrates have a relatively brief life cycle and their anatomy is not particularly complex, thereby allowing researchers to more easily study them and draw appropriate conclusions. Invertebrates are also readily abundant. Therefore, large numbers of invertebrates can be studied within a single experiment. In addition, invertebrates tend to carry lower research costs in comparison with other animals used for testing. A researcher does not require individual cages and waste or food disposal for each invertebrate. In fact, literally hundreds or thousands of flies, for instance, could be kept in one sheltered area.
Disadvantages of Using Invertebrates in Animal Testing
Although there are many benefits to using invertebrates in animal testing, there are also some distinct disadvantages. Invertebrates can be useful precisely because their anatomy is so simple, yet this very fact also presents a disadvantage for scientists. Their organs are extremely undeveloped and simple and they also do not have the adaptive immune system of other animals. These differences in comparison with humans generally prevent their successful use in medicine and health research. Thus, much of the applied biomedical research that occurs can't utilise invertebrates for important areas such as the development of cancer drugs, vaccines and the understanding of human biology. On top of that, diseases that occur in invertebrates are usually very different from those occurring in humans, which further limits their use in biomedical research testing.
Important Uses for Invertebrate Testing
Although a range of invertebrates is used for testing purposes, commonly used ones include fruit flies and nematodes. Current research efforts using invertebrates have improved the understanding of how animals develop, genetically speaking. Due to its simple structure, the full lineage of a type of nematode is known and the genome is completely sequenced. This means that researchers can learn how the nematode develops from initial cell to adult. The genes can be manipulated to create a desired effect in the process of understanding biology and disease. One notable aspect of research on the nematode occurred when scientists learned that certain cells in the nematode are essentially set or programmed for death during their development. This discovery showed how genes control the life of a cell. In addition, the nematode's very basic nervous system has allowed researchers to study how genetics influence nerve development.
As mentioned, fruit flies are also commonly used in invertebrate research testing. They are particularly useful in genetics research and their easy housing and care means that they can successfully be used in larger numbers. At the cellular level, these organisms are quite simple, which allows researchers to create an array of flies with modified genetics, thereby allowing them to better study biology and disease. Researchers can then learn more about the cellular cycle itself as well, in addition to gaining knowledge of animal behaviour and neurology.
Choice of Animals for Testing
Fortunately, researchers do have a broad choice of animals for research testing. This allows them to choose the most suitable animal for the research aims and it also helps to ensure that animals welfare is maximised and suffering minimised. Invertebrates clearly offer some important benefits over other animals and their use has taught us a great deal about genetics. Hopefully, continued research with invertebrates will yield additional information that benefits our knowledge.