1Department of Veterinary Microbiology, Madras Veterinary College, Tamil Nadu Veterinary and Animal Sciences University, Chennai-600007, India
Department of Veterinary Parasitology, Madras Veterinary College, Tamil Nadu Veterinary and Animal Sciences University, Chennai-600007, India
*Corresponding author. Email: selvarayararunkumar@gmail.com
Online Published on 29 March, 2022.
Anaplasma ovis is an obligate epicellular rickettsial pathogen transmitted by ticks and causes anaplasmosis in small ruminants. The present study aimed to detect and characterize A. ovis in ixodid ticks of small ruminants in two districts of Tamil Nadu, by using msp4 gene fragment as the target. A total of 2096 ixodid ticks were collected from sheep and goats and identified morphologically. Salivary glands were separated from the ticks and DNA was extracted. Subsequently PCR amplification of msp4 gene was carried out and the 831bp PCR product was sequenced. A total of 29.75% (122/410) of pooled samples of ticks were positive for A. ovis. The nucleotide sequences of msp4 gene were analyzed and phylogenetic tree was constructed. The nucleotide sequences of sheep and goat isolates of A. ovis in this study were 100% identical. They also showed perfect similarity with the sequences of A. ovis in public database. Based on the study, it was concluded that Rhipicephalus haemaphysaloides and Haemaphysalis bispinosa could act as possible vectors for A. ovis.
Anaplasma ovis, Msp4 gene, PCR assay, Phylogenetic tree
