ABSTRACT
Parasites are organisms that live in a symbiotic relationship in or on other organisms (hosts), which are normally of a different species. They exhibit a high degree of specialization with respect to their hosts and in uence host tness. Parasites whose symbiotic relationships occur primarily within the body of a host are known as endoparasites, while those whose symbiotic relationships occur primarily at the outer surface of their hosts are known as ectoparasites. Although parasites affect most life forms, causing some harm, this chapter focuses on the extraction of nucleic acids from those eukaryotic parasites known to cause disease, morbidity, and mortality in human beings and livestock.
