Epidemiological Studies on Bovine Anaplasmosis

Abstract

This study carried out at Dakahilia and Daimetta provinces in Nile Delta, Northern Egypt. For determination, the current existence of bovine anaplasmosis in cattle populations, in Dakahlia province 650 cattle of different ages (all of them were over six months), and 4640 in Daimetta province were investigated. From suspected cases the peripheral blood smears were examined microscopically. For characterization the risk of anaplasmosis, 350 cattle over 24 weeks were sampled for seroepidemiological survey and assessing endemic stability (100 from sporadic field cases and small holders randomly selected and 250 from intensive system farms). The prevalence of A. marginale through Giemsa stained blood smears positivity was found to be (6.30 %) in sporadic field cases and small holders> sector and (9. 05%) in intensive system sector. Blood smears positivity cleared a seasonal pattern and an age profile with significant differences. In sporadic farmers and small holders sector at Dakahlia province; seroprevalence by IFAT for A. marginale was found to be (42%) in sporadic field cases and small holders sector & (61.2%) in intensive system sector, indicative of a situation of endemic instability with significant clinical disease risk in both sectors. In investigated intensive farms in Daimetta province some anaplasmosis outbreaks happened in absence of tick-vector that may indicate that stress and mechanical transmission are key factors in the expression of the disease within infected herds.