关键词: 青海田鼠, 疫源地, 监测

Abstract: Objective:To determine the sampling method for Microtus fuscus,sample amount of parasitic fleas on surface of Microtus fuscus and the least sampling amount for pathogenic and serological methods.Methods:6 specimen squares were investigated and analyzed by using analysis of variance to determine appropriate sampling areas of Microtus fuscus ;A modified formula of the oretical sampling quantity of no repeat sample observed unit of rate:n=log^-1(p)(q ²N/(pq+Nd) was employed to ascertain the sampling amount of parasitic fleas on surface of Microtus fuscus;The lowest sampling amount of pathogen and serology were estimated by the formula:n=log(a)/log(1-P)+1,a= 0.05.Results:When the density of Microtus fuscus was more than 100 per hectare,or specimen square was more than 400 m²,this investigating area was determined for Microtus fuscus sampling area.50-100 Microtus fuscus were checked per mensem for the investigation of parasitic fleas on surface of Microtus fuscus.The reliability was above 95%.In the collectivity,during Microtus fuscus epizootic plague spreading,with the formula of the lowest sampling amount tested,one infected Microtus fuscus could be found from at least 37 Microtus fuscus to be checked.One died infected Microtus fuscus could be found from at least 8 died Microtus fuscus to be checked.One captured infected Microtus fuscus could be found from at least 221 captured Microtus fuscus to be checked.One positive serum could be found from at least 24 serum samples from Microtus fuscus or 18 serum samples from canine to be checked.Conclusion:To Investigate the specimen square more than 400 m²,more than 50 Microtus fuscus per mensem for surface parasitic fleas and more than 220 Microtus fuscus for Yersinia pestis in the plague nature foci.