Spatial pattern of rodent population, animal plague and risk analysis in eastern part of Ningxia desert grassland

Objective To find out the spatial pattern of rodent population and risk of animal plague in eastern part of Ningxia desert grassland.Methods Monitoring and survey data of grassland rodents and parasitic fleas of estern desert steppe in Ningxia from 2002 to 2012 were collected and processed; capture rate,flea infection rate and flea index rate were calculated.Results From 2002 to 2012,the capture rate of the mouse that moves at daytime ranged from 1.10 to 5.90/hm2,and these mice belonged to three species,namely the dominant species Meriones unguiculatus,common species Spermophilus dauricus,and rare species Ochotona daurica.Nocturnal mouse capture rate ranged from 3.82％ to 18.97％,and these mice had a population diversity,which belonged to 2 orders,6 families,7 genera and 15 species.Meriones meridianus,Phodopus roborovskii and Dipus sagitta were the dominant species,Cricetulus barabensis,Mus musculus,Cricetulus migratorius and so on as the common species and Microtus fortis,Rattus norvegicus and so on as the rare species.From rats and parasitic fleas,123 strains of Yersiniapestis were detected,106 of them were detected in rats(104 from dead rodent,2 from live rats),and 17 from parasitic fleas.Conclusions The risk of animal plague in eastern Ningxia desert grassland has increased; we suggest to further improve and implement the regional joint prevention and control measures,and effectively control the spread of the plague. Key words: Plague;  Rodent;  Desert grassland;  Spatial pattern;  Risk assessment