Epidemiology and phylogeny ofthrough internal transcribed spacer 2 gene in small ruminants.

Abstract

INTRODUCTION: () is a blood-feeding nematode causing infectious disease haemonchosis in small ruminants of tropical and subtropical regions around the world. This study aimed to explore the prevalence and phylogeny ofin small ruminants using the internal transcribed spacer-2 (ITS-2) gene. In addition, a comprehensive review of the available literature on the status ofin Pakistan was conducted. METHODS: Fecal samples were collected from sheep and goats ( = 180). Microscopically positive samples were subjected to DNA extraction followed by PCR using species-specific primers. RESULTS: The overall prevalence ofwas 25.55% in small ruminants. The prevalence ofwas significantly associated with months and area. The highest occurrence of haemonchosis was documented in July (38.70%), whereas the lowest occurred in December (11.11%), with significant difference. The prevalence was highest in the Ghamkol camp (29.4%) and lowest in the arid zone of the Small Ruminant Research Institute (17.5%) ( = 0.01). The results of the systematic review revealed the highest prevalence of haemonchosis (34.4%) in Khyber Pakhtunkhwa ( = 0.001). DISCUSSION: Phylogenetic analysis revealed a close relationship betweenand isolates from Asia (China, India, Iran, Bangladesh, Malaysia, and Mongolia) and European countries (Italy and the United Kingdom). It has been concluded thatis prevalent in small ruminants of Kohat district and all over Pakistan, which could be a potential threat to food-producing animals, farmers, dairy, and the meat industry. Phylogenetic analysis indicates thatisolates share close phylogenetic relationships with species from Asia and Europe.