Molecular characterization of Setaria equina infecting donkeys (Equus asinus) from Egypt

Abstract

Objective: Since few molecular data about Setaria equina are available, as this study proposed in order to investigate the molecular characteristics and the phylogenetic position of S. equina isolates from donkeys which was previously studied in horses. Methodology: The DNA was extracted from adult worms of S. equina found in the peritoneal cavity of donkeys slaughtered at Giza Zoo Abattoir, Egypt. A fragment length of the cytochrome oxidase subunit 1 (COX 1) gene (683 bp) was amplified using PCR. Purified PCR product was sequenced. Sequences were aligned with those published on GenBank and subsequently, the phylogenetic tree was constructed. Results: Results of the BLAST search showed that our isolates from donkeys are homologous (99% identity) with that from horses (AJ544873). Phylogenetic analysis exhibited the sister relationship between S. equina isolates from both donkeys and horses which illustrates the conspecificity between them and suggesting the cross transmission of this parasite species among different equids. Conclusion: The genetic relevance of this parasite to the other filarial worms was discussed in details. This is the first report about the molecular identification of S. equina infecting donkeys from Egypt.