Preliminary investigation on rodent–ectoparasite associations in the highlands of Tigray, Northern Ethiopia:implications for potential zoonoses

We studied associations between rodents and their arthropod ectoparasites in crop fields and household compounds in the highlands of Tigray,Northern Ethiopia.Ectoparasite infestation indices,such as percent infestation,mean abundance,prevalence and host preferences,were calculated for each taxon.In total,172 rodents from crop fields and 97 from household compounds were trapped.Rodent species and numbers trapped from the crop fields and household compounds were Mastomys awashensis(Lavrenchenko,Likhnova&Baskevich,1998)(88 and 44),Arvicanthis dembeensis(Ruppel,1842)(63 and 37)and Acomys sp.(21 and 16),respectively.A total of 558 insects and acarids(belonging to 11 taxa)were recovered from the rodents trapped in the crop fields,and 296 insects and acarid(belonging to 6 taxa)from the rodents trapped in the household compounds.Approximately 66%of the rodents trapped from the crop fields and 47%of those trapped from the household compounds were infested with ectoparasites.Laelaps sp.(64.9%)and Xenopsylla sp.(20.6%)comprised the highest proportion of the ectoparasites recovered in the crop fields,and the same ectoparasites,but in reverse order,comprised the highest proportions in the household compounds(Xenopsylla[50.3%]and Laelaps sp.[29%]).Our study revealed that crop fields and household compounds in the highlands share similar rodents and several ectoparasites.Furthermore,at least 1 of the rodent species and some of the ectoparasites identified in this study were reported to have posed medical and veterinary threats in other parts of Ethiopia and neighboring countries.