Molecular characterization of Moniezia denticulata (Rudolphi, 1810) and its distinction from M. expansa infecting sheep and goats raised in the north and north-western regions of India

The tapeworms of Moniezia spp. are heteroxenous parasites and their adult forms occur in ruminants' alimentary tract. They steal a significant portion of hosts' nourishment initiating monieziasis, thereby inflicting economic losses in animal rearing. Despite their high economic importance, the molecular characterization and taxonomic status of these parasites have remained poorly understood. In the present study, cestodes were isolated from the sheep and goats' intestines and were stained with Gower's carmine. Upon careful evaluation of morphological characters, 2 species Moniezia denticulata and Moniezia expansa were identified. The genomic DNA was extracted and polymerase chain reaction (PCR) amplified targeting regions of mitochondrial cytochrome c oxidase subunit 1 (cox1), small subunit ribosomal RNA (SSU rRNA) and internal transcribed spacer 1–5.8S rRNA (ITS1–5.8S rRNA) genes followed by sequencing. The partial sequences of cox1, SSU rRNA and ITS1–5.8S rRNA genes of M. denticulata generated in the present study revealed that even though they share high similarities with M. benedeni (93.2% cox1; 92.6% SSU rRNA; 84.70% ITS1–5.8S rRNA) and M. expansa (88.85% cox1; 92.27% SSU rRNA; 81.70% ITS1–5.8S rRNA), they are not identical to them. In the maximum likelihood phylogenetic trees, M. denticulata and M. expansa consistently appeared as distinct species from each other. The high values of pairwise divergence between these 2 species collected in the present study confirmed their separate identity. The present study reports the first molecular characterization of M. denticulata with reference to M. expansa infecting sheep and goats in India.