【Abstract】 Objective To understand the ectoparasite communities in a population of Eothenomys miletus in the surrounding areas of Erhai Lake and describe the importance of them in the medicinel and veterinary. Methods Investigation sites were randomly selected at different direction of surrounding areas of Erhai Lake in Yunnnan. Small mammals were captured by live traps with baits. The live traps were examined and the baits were changed each morning. Trapped small mammals were brought to the laboratory to identify according to their body shape, size and color, and some measurements such as body length, ear length and hind feet length, and ectoparasites were collected. Ectoparasites were identified under a microscope after mounting, clearity and desiccation. The constituent ratio (C), prevalence (P) and average ectoparasite abundance (A) were used to reflect the prevalence and density of ectoparasites. Non-parametric Mann-Whitney U-tests were used to test differences in the abundance and richness of ectoparasites between female and male hosts. Spearman correlation analysis was used to analyze the relationship between ectoparasites and the body parameters of hosts. Results There were 916 E.miletus caught. Of which, a total of 756 were infested by ectoparasite, and the infestation rate was 83%. A total of 86 species of ectoparasite were collected, including 51 species of chigger mite, 23 species of gamasid mite, 7 species of flea and 5 species of sucking louse. Seventeen species were proved to be the main vectors of human disease. Conclusion There was very high diversity of ectoparasites parasitized on E.miletus, and some species had been reported to be associated with human disease. E.miletus could be a natural reservoir of plague bacilli, epidemic haemorrhagic fever (korean haemorrhagic fever) viruses and scrub typhus.

Objective To understand species composition of gamasid mites on the body surface of Rattus flavipectus(a dominant species of domestic rats in Yunnan,China) and species diversity.Methods Twenty-five counties(towns) in Yunnan province were chosen to investigate the ectoparasitic gamasid mites on the body surface of R.flavipectus.All the individuals of R.flavipectus were randomly captured by mouse-traps and the gamasid mites on the body surface of R.flavipectus were all collected.Every individual of the gamasid mites was mounted on a glass slide after the dehydration and clarification in a conventional way.The mounted specimens of the gamasid mites were finally identified under a microscope.Results(18 250) gamasid mites were collected from the body surface of(3765) captured rats R.flavipectus and all the mites were identified as 40 species of 17 genera in 9 families.Of the 40 species of gamasid mites,three gamasid mite species(Laelaps nuttalli, L.echidninus and O.rnithonyssus bacoti were the dominants. L.nuttalinushas(10 667) individuals collected((58.45%)) while L.echidninus (5124)((28.08%)) and O.bacoti(1286)((7.05%)).37 species of gamasid mites are found in the southwest mountainous subregion in zoogeography with three dominant species, L.nuttalli((51.74%)), L.echidninus((29.74%)) and O.bacoti((11.40%)).In comparison with the species in the southwest mountainous subregion of Yunnan,less species of the mites(25 species) are collected in the southern mountainous subregion of Yunnan with two dominant mite species, L.nuttalli((64.35%)) and L.echidninus((26.61%)).Conclusion The ectoparasitic gamasid mite species on R.flavipectus in Yunnan province are very abundant and the species compositions of the gamasid mites are different in different zoogeographical regions.

Objective To understand the species composition,species distribution,the dominant species and their spatial pattern of ectoparasitic chigger mites on Rattus flavipectus(a dominant species of rats in Yunnan,China).Methods R.flavipectus(the host of mite) was captured with cage trap method in 16 counties(or towns) of Yunnan.All the mites on the two auricles surface of the hosts were completely collected,made into specimens and then identified under a microscope.The patch index (m*/m) was adopted to judge the spatial distribution patterns of the dominant chigger mite species among the different individuals on their rat hosts R.flavipectus. Results 725 individuals of R.flavipectus were captured only in 13 ones of those 16 counties(towns).(2 710) chigger mites(belonging to 3 subfamily,10 genus,42 species) were collected from the auricles(body surface) of 725 rat hosts R.flavipectus with high mite infection rate and mite index.There are four dominant mite species: Ascoschoengastia indica, A.leechi, Walchia micropelta and Microtrombicula munda.Conclusion(The chigger) mites species on R.flavipectus is very abundant with more individuals.The distribution of the chigger mites among different individuals of R.flavipectus is of an aggregation pattern.

Objective To understand the fauna of ectoparasitic sucking lice on small mammals in Yunnan Province of China. Methods Nine counties(towns) in Yunnan Province were chosen as target sites to investigate the sucking lice on small mammal hosts. The hosts were captured by traps. The sucking lice on the body surface of small mammals were all collected. Every individual of the sucking lice was dehydrated,made to be transparent mounted on slides in a conventional way,and then identified under a microscope. Results 2 745 small mammal hosts were captured and 18 167 sucking lice from the hosts were collected. The 2 745 hosts were identified as 41 species of 25 genera of 10 families in 5 orders: Rodentia,Insectivora,Scandentia,Logomorpha and Carnivora. The collected 18 167 sucking lice were identified as 22 species of 6 genera of 4 families. All the louse species,together with their taxonomic position (genera and families),their hosts and collected sites were listed in detail. Conclusion There are relatively less sucking lice species on the small mammals,and the number of species of sucking lice are much less than the number of species of the hosts.

Objective To understand the species and distribution of sucking lice on small mammals in Dali,Yunnan Province,China.Methods The small mammals are captured by mouse traps.The sucking lice on the body surface of small mammals were all collected.Every individual of the sucking lice was made into slide in a conventional way and then identified.Results 636 individuals of 22 species of small mammals were captured and 8 051 individuals of sucking lice from the hosts were collected.The collected lice are identified as 14 species of five genera of four families.There are only one or two species of lice on most small mammals body surface and few hosts have three or four louse species.The louse communities on small mammal hosts are quite simple with lower species richness and diversity and with a high dominance index.Conclusion Small mammals usually have fewer species(one or two species) of sucking lice on their body surface with less species diversity.Most species of sucking lice usually have a high host specificity.