Controlling fertility of rodent pests has become an effective means of controlling the population of grassland rodents in China. Recently, research has focused on how to select environmentallyfriendly sterilants without pollution effects, and to realize sustainable control of pest rodent populations. Sterilants from plant extracts have been mainly selected. In this study, mice were used as the experimental subjects for research on the anti-fertility effects of plant extracts of shikonin and the anti-fertility mechanism of shikonin extract was determined. The mice were divided into four groups, including one control group and three experimental groups. There were three applications of shikonin extract in different concentrations (5 mg•kg −1 , 20 mg•kg −1 and 50 mg•kg −1 ). The mice gavage experiments indicated that a shikonin concentration of 50 mg•kg −1 had the expected anti-fertility effects. Mice copulation experiments showed that the 50 mg•kg −1 shikonin treatment had significant anti-fertility effects on both female-treatment and female-male-treatment groups. The results of the PCR analysis on the AgRP and ghrelin mRNA from female ovaries and male testicles indicated that shikonin could control mice reproduction by regulating the pituitary gonadal axis. Shikonin, as plant source sterile agent, would have more ideal effects for functioned both sexes sterility.

The Transbaikal zokor (Myospalax psilurus) is a dominant rodent distributed in the meadow steppe of Inner Mongolia in northern China. Due to long history of evolution in subterranean environment, the zokor has an adaptive behavior: sealing burrow entrances. When a burrow is damaged, exposed entrances appear, and within a relatively short time, the zokor would be active in sealing the entrances to reduce risks to its survival. In general, it is thought that zokors avoid light and wind, which is consistent with their behavior of sealing burrow entrances. However, direct evidence from field experimental research has been lacking. This study set up 68 field sampling points in a meadow steppe in Inner Mongolia from August to September, 2014 and used a wind–light isolator to study the effects of wind and light factors on zokor burrow entrance sealing behavior. The results showed that there were no significant correlations between wind or light factors and the frequency of zokor burrow entrance sealing. Therefore, wind and light factors are not direct factors associated with zokors actively sealing burrow entrances.

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