Prevalence and Identity of Taenia multiceps cysts “Coenurus cerebralis” in Sheep in Egypt

Abstract

Coenurosis is a parasitic disease caused by the larval stage (Coenurus cerebralis) of the canids cestode Taenia multiceps. C. cerebralis particularly infects sheep and goats, and pose a public health concerns. The present study aimed to determine the occurrence and molecular identity of C. cerebralis infecting sheep in Egypt. Infection rate was determined by postmortem inspection of heads of the cases that showed neurological manifestations. Species identification and genetic diversity were analyzed based on PCR-sequence analysis of nuclear ITS1 and mitochondrial cytochrome oxidase (COI) and nicotinamide adenine dinucleotide dehydrogenase (ND1) gene markers. Out of 3668 animals distributed in 50 herds at localities of Ashmoun and El Sadat cities, El Menoufia Province, Egypt, 420 (11.45%) sheep showed neurological disorders. Postmortem examination of these animals after slaughter at local abattoirs indicated to occurrence of C. cerebralis cysts in the brain of 111 out of 420 (26.4%), with overall infection rate 3.03% of the involved sheep population. Molecular analysis of representative samples of coenuri at ITS1 gene marker showed extensive intra- and inter-sequence diversity due to deletions/insertions in the microsatellite regions. On contrast to the nuclear gene marker, considerably low genetic diversity was seen in the analyzed mitochondrial gene markers. Phylogenetic analysis based on COI and ND1 gene sequences indicated that the generated sequences in the present study and the reference sequences in the database clustered in 4 haplogroups, with more or less similar topologies. Clustering pattern of the phylogenetic tree showed no effect for the geographic location or the host species.