MOLECULAR IDENTIFICATION OF GASTROINTESTINAL NEMATODES GENERA OF DOMESTIC RUMINANTS USING FRAGMENT ANALYSIS
Autor(es): LIVIA LOIOLA DOS SANTOS, RONALDO LUIZ NUNES, DANIELLE CUNHA CARDOSO, EDUARDO BASTIANETTO, MARCELA GONÇALVES DRUMMOND, BRUNO S. ALVES FIGUEIREDO BRASIL, DENISE APARECIDA ANDRADE DE OLIVEIRA
MOLECULAR IDENTIFICATION OF GASTROINTESTINAL NEMATODES GENERA OF DOMESTIC RUMINANTS USING FRAGMENT ANALYSIS
» Área de pesquisa: HELMINTOLOGIA
» Instituição: UNIVERSIDADE FEDERAL DE MINAS GERAIS
» Agência de fomento e patrocinadores: CNPq 573899/2008-8
FAPEMIG APQ-0084/08
CAPES
Gastrointestinal nematode infections constitute a significant threat to the health and welfare of livestock in Brazil and are responsible for significant economic losses. The species belonging to the genera Haemonchus and Cooperia are the most prevalent in cattle while the genus Teladorsagia, Trichostrongylus, Haemonchus and Oesophagostomum are the most common among sheep and goats. These genera present different degrees of prolificacy and pathogenicity and, therefore, species identification is key to a sustainable parasite control. Nevertheless, traditional methods to identify these parasites are based on morphology features and are laborious, time-consuming and have limited scalability. In this context, DNA-based tests can provide higher sensitivity, specificity and potential for automation. ITS-2 (Internal Transcribed Spacer 2) is a well conserved nuclear region used in taxonomic studies due to its universality and good resolution among closely related species. The aim of this study was to develop and standardize a high throughput molecular method for the identification of parasitic nematodes of ruminants using fragment analysis. Adult worms of the most prevalent genera in Brazil were morphologically identified and its ITS- 2 region were sequenced. Given the abundance of InDel mutations in ITS-2 region, it could be observed that each nematode genera studied yielded a specific fragment size. Therefore, by using specific primers for this region, it was possible to identify - using capillary electrophoresis in an automated sequencer - the presence of the genus Haemonchus, Cooperia and Ostertagia in the DNA extracted from different samples, including eggs, larvae and adult worms. To develop a method to accurately identify strongylid nematodes of domestic ruminants is important not only in diagnosis and control of the diseases they cause, but in studying their epidemiology and systematics.
