Effects Of Sterility Controlling On Dominant Rodents Wild Populations In Alashan Desert Of Inner Mongolia

From March to October in2011, we used EP-1(levonorgestrel-quinestrol), the compound sterility mixture, controlling contrast experiments on dominant rodents wild populations by single baiting with EP-1in spring in Alashan Desert, Inner Mongolia. The results showed:(1) In the treatment area, the weight and size of reproductive organs for males were obvious atrophy and lighten, and the down rates of testicles were decreased. Compared with the control area, the reproductive organs of Meriones meridianus and Dipus sagitta were extremely different (P<0.01), and recovered the average level after the third months. However the weight of Phodopus roborovskii’s testicle were lower than those of the control area (P<0.05), and the fertility control was sustained for a long duration.(2) In the treatment area, the females’uterus were edema, and the uterus wall thinning like semi-transparent. The uterine cavity was filled with liquid, and becomes larger in volume. The most obvious changes were for Meriones meridianus and Dipus sagitta. However the uterus of Phodopus roborovskii was significant difference compared with which of the control area in April (P<0.05). And the average amounts of fetuses of dominant population of desert rodent were significant difference compared with those of the control area in May (P<0.05).(3) The EP-1disturbed the principle of dominant population growing of desert rodent. The seasonal fluctuations were obvious double-peak curves in control area, but the dominant population growing was significantly declined in the treatment area. The captured ratio of Meriones meridianus was significant lower than which of the control area during their two reproduction-peaks (P<0.05). And the captured ratio of Phodopus roborovskii was significant lower than which of the control area from August to September (P=0.05), the captured ratio of Dipus sagitta was significant lower than which of the control area from April to May (P<0.05).(4) The age structures of dominant population produced significant changes in the first three months after single baiting. The proportions of juveniles in population were significant lower than those of the control area from April to June (P<0.05). and the juvenile individuals of dominant populations appeared within August and September in treatment area. The proportions of adult of Meriones meridianus and Phodopus roborovskii were obvious higher than those of control area (P<0.05).