First molecular identification of Spirometra erinaceieuropaei, Ligula intestinalis, and Taenia hydatigena infecting wildlife canine and avian hosts from the Astrakhan Region, Russia

Wild animals play a crucial role as maintenance and reservoir hosts for parasitic diseases that can affect both human and animal populations. This study aimed to identify and molecularly characterize three cestodes infecting wild canid and avian hosts in the Astrakhan Region, Russia. Intestinal samples were collected from fifty carcasses, including 11 Nyctereutes procyonoides (N. procyonoides), 23 Canis aureus (C. aureus) as mammal hosts, and 16 Ardea cinerea (A. cinerea) as avian hosts, collected from roadkill or animals culled by predators in forests. The collected cestodes were thoroughly rinsed with ice-cold phosphate-buffered solution (PBS, pH 7.2) and then preserved in 70% ethanol for microscopic and molecular examination. Genomic DNA was extracted and subjected to molecular characterization using PCR amplification of partial cytochrome c oxidase subunit-1 (COX-1) and 18S rRNA gene fragments. Identified cestode species included Spirometra erinaceieuropaei from N. procyonoides, Ligula intestinalis from A. cinerea, and Taenia hydatigena from C. aureus, with infection rates of 9% (1/11), 12.5% (2/16), and 17.4% (4/23), respectively. PCR amplification yielded fragments of approximately 1566 bp (COX-1) for Spirometra erinaceieuropae, 396 bp (COX-1) for Ligula intestinalis, and 1256 bp (18S rRNA) for Taenia hydatigena, with NCBI accession numbers PP002116-PP002117, PP002294-PP002285, PP002255-PP002412, respectively. This study discloses the first molecular genotyping data of three cestodes isolated from wild canid and avian hosts in the Astrakhan Region, Russia. The findings underscore the ecological and public health significance of wildlife as reservoirs of zoonotic helminths, emphasizing the need for continuous molecular surveillance and effective control measures to prevent cross-species transmission.