Seasonal Occurrence Of Fleas And Other Ectoparasites On Small Mammals At Waterberg Plateau Park, Namibia

ABSTRACT

Fleas and other ectoparasites infesting small mammals were studied from December 2005 to June 2006 at Waterberg Plateau Park, Namibia. The main aim of this study was to investigate seasonal occurrence of fleas and other ectoparasites on small mammals at selected sites at Waterberg Plateau Park. Small mammals were live-trapped, marked and released. Ectoparasites were collected (by brushing) from these small mammals before they were marked and released. Fleas, ticks and lice were stored in 70% ethyl alcohol, whereas mites were stored in Oudeman’s fluid before being processed and prepared for identification purposes.

A total of one hundred and seventy nine (179) small mammals belonging to 11 rodent species (Aethomys namaquensis, Aethomys chrysophilus, Dendromus melanotis, Graphiurus murinus, Gerbirullus paeba, Gerbirullus vallinus, Mus indutus, Mastomys spp., Saccostomus campestris, Tatera leucogaster & Thallomys nigricauda) and 1 shrew (Crocidura hirta) were captured and examined. A total of one hundred and fourteen (114) fleas belonging to eight (8) species (Listropsylla aricinae, Listropsylla dorippae, Pulex irritans, Xenopsylla brasiliensis, Xenopsylla cheopis, Xenopsylla nubica, Xenopsylla philoxera & Xenopsylla versuta) and fifteen (15) ixodid ticks belonging to three (3) species (Haemaphysalis elliptica, Hyaloma truncatum & Rhipicephalus neummani) were recovered. Additionally, three lice (3) and four hundred & sixty nine (468) mites were recovered but could not be identified. During the present study, a larva belonging to a tick species R. neumanni was collected for the first time from the wild. Again, a nymph of R. neumanni was recorded for only the second time in the wild in whole of Southern Africa. Generally, prevalence, intensity of infestation, and species diversity of ectoparasites varied among the 5 months, host species and between host sexes. Prevalence, intensity of infestation, and species diversity of ectoparasites was generally higher in December and lower in March; higher in T. leucogaster than Mastomys spp. & G. paeba and no ectoparasites were collected from C. hirta, G. murinus, G. vallinus and S. campestris. There was no significant difference in prevalence, intensity of infestation and species diversity of ectoparasites (except in prevalence of mites) between female and male hosts, fleas (prevalence: U=8.0, P=0.347; intensity: U=11.0, P=0.754; species diversity (H’): U=11.0, P=0.754); ticks (prevalence: U=9.0, P=0.465; intensity: U=11.0, P=0.735; species diversity (H’): U=7.5, P=0.296); mites (prevalence: U=2.0, P=0.028; intensity: U=9.0, P=0.465). However, fleas showed evidence of seasonality in the prevalence of infestation (H=5.58, df=4, P