Abstract
Animals are routinely exposed to parasites from different taxonomic groups resulting in significant morbidity, mortality and economic losses. Accurate identification of the responsible parasites is central to the understanding and management of these infections and associated diseases. Comprehensive approaches to facilitate the diagnosis of parasites and parasitic diseases will yield better insight into their basic biology, epidemiology, pathogenicity, and the development of treatment strategies. Traditionally, the diagnosis of parasitic infections mainly relies on testing for the presence of parasites through direct fecal examination, blood smears, etc, but clinically, it is often difficult to elucidate the entire offending organism. Techniques for diagnosis of parasites such as counting parasites are often time-consuming, difficult, inaccurate, of limited sensitivity, and occasionally unpleasant. While the majority of parasites exhibit multiple stages during the course of their life cycles, the nucleic acids extracted from them during these different periods remain identical. PCR, providing exquisite sensitivity and specificity for detection of nucleic acid targets, has become one of the most important tools in parasite diagnostics. Real-time PCR has simplified and accelerated PCR procedures and has reduced complications associated with traditional PCR, such as cross-contamination. Molecular biology tools, such as PCR, are increasingly relevant to veterinary parasitology. This chapter focuses on the application of real-time PCR for parasite detection and differentiation, exemplified in protozoa, helminthes and arthropods, significant parasites in veterinary medicine and public health.