First molecular detection and phylogenetic analyses of Neospora caninum from naturally infected sheep in North Africa

Abstract

Neospora caninum is a protozoan parasite from the phylum Apicomplexa. This parasite is as one of the major causative abortive agents in the dairy cattle industry. Moreover, abortions in sheep due to N. caninum have been reported by several studies (Moreno et al, 2012). The objective of this study was to estimate the molecular prevalence and phylogenetic analyses of N. caninum in Tunisian sheep. A total number of 198 meat samples were collected from slaughtered ewes and tested for the presence of N. caninum ITS1 gene using PCR followed by sequencing of some PCR products. A phylogeneyic tree was then constructed to compare the partial sequences of the ITS1 gene with GenBank sequences. The overall N. caninum infection prevalence rate in sheep was 10.6±4.3% (21/198). The infection rate was significantly higher for animals aged over one year (19.4±9.1%) when compared to those under one year of age (5.6±4) (p<0.001). The highest prevalence was observed in North Béja locality (31.2±16.1) (p<0.001). Compared to Barbarine (6.8±4.5%) and Cross-bred animals (0%), Noire de Thibar was the most infectedsheep breed (31.7±14.2%) (p<0.001). Comparison of the partial sequences of the ITS1 gene revealed 96-98% similarity among our N. caninum amplicon and these deposited in GenBank. To our knowledge this is the first molecular study and phylogenetic analysis of N. caninum in sheep in North Africa. Our results indicate the meat harbour N. caninum cysts and can contribute to a better evaluation of N. caninum infection and the associated abortions in sheep.