Abstract

During buffaloe OSD spread in a village affiliating to Assiut Governorate-Egypt, 44 buffaloe cows hosted and owned sporadically were subjected to the study. From 43 buffaloe cows (had closed lesions either edematous or nodular) and a buffaloe cow (had open ulcerative lesion), Corynebacterium pseudotuberculosis equi (C. ps. equi) as 72% and Corynebacterium pseudotuberculosis ovis (C. ps. ovis) as 28% were isolated and identified. Blood sucking insects hosted on the infected buffaloe cows (no. 22) louse fly(Hippobosca equine) and 20 Haematopinus eurysternus lice were included during the study where both C. ps. equi and C. ps. ovis were isolated from Hippobosca equina ( H equina) but failed to isolate any biovar of C. ps. from Haematopinus eurysternus lice (H. eur.). Moreover, C. ps. equi was isolated from two H equina pupae #x2013; lab deposited #x2013; as well as a H equina second generation fly concluding that there is endosymbiosis nature of C.ps. limited only to H. equina fly which can transmit C.ps. vertically.