The tick species of domestic livestock in the Republic of Mali, West Africa

Abstract

As part of a vector survey program in the Republic of Mali, West Africa from 1977 to 1981, 23,769 ticks were collected mostly from domestic animals. Approximately 98% of the specimens belonged to 20 currently recognized species or subspecies: Amblyomma variegatum, Aponomma flavomaculatum, Ap. latum, Boophilus annulatus, B. decoloratus, B. geigyi, Hyalomma dromedarii, H. impeltatum, H. impressum, H. marginatum rufipes, H. nitidum, H. truncatum, Rhipicephalus cuspidatus, R. evertsi evertsi, R. guilhoni, R. lunulatus, R. muhsamae, R. sanguineus, R. senegalensis, and R. sulcatus. Two groups and a separate single specimen of Rhipicephalus ticks exhibited relatively unique combinations of morphological characters and are described herein as Rhipicephalus group(s) #9 and 10 and specimen #11, respectively. Micrographs of all the aforementioned species and specimen groups were produced by light and electron microscopy. The accepted morphologies of H. nitidum, H. truncatum and R. cuspidatus from Mali were reviewed because some essential characters differed significantly from those currently used in their taxonomy. Supernumerary hypostomal dentition was recorded and discussed in Boophilus specimens. Features of female gonopore tissues proved to be characteristic and constant enough to suggest use in distinguishing species of ixodid ticks excepting genus Ixodes. Of all species encountered, A. variegatum, B. geigyi, H. m. rufipes and H. truncatum had the widest host ranges and occurred, with varying degrees of success, in all areas surveyed. The remaining species showed restricted distributions determined primarily by rainfall, vegetation, topography and host availability. Cattle were readily attacked by most tick species, sheep and goat to lesser extents, and multiple tick species infestations were common to all 3 hosts. The Ndama cattle breed usually carried fewer ticks than the Zebu in the Sudan region of Mali where both breeds were represented by large numbers. Wildlife inspected during the survey usually carried high tick burdens, especially immatures.