We first report the effect of a compound EP-1 (mixture of levonorgestrel and quinestrol) on male greater long-tailed hamsters (Tscherskia triton). Hamsters in the treatment group were provided with wheat baits with 0.001% EP-1 for six consecutive days, while hamsters in the control group were provided with plain wheat. One week and three weeks later, reproductive organs of hamsters of both groups were measured, respectively. We found the size or weight of testis, spermatophore and epididymis of the treatment group were significantly reduced compared to those of the control group, and this reduction was greater in the third week compared to that of the first week. The results indicate that EP-1 is able to reduce the fertility of both male and female hamsters.
To investigate differences of size and shape of skulls among rodent species and between male and female,we radiographed specimens and measured parameters of skulls of three species(Tscherskia triton,Cricetulus barabensis and Apodemus agrarius) collected from the Raoyang country,Hebei Province,China.The data was analyzed with MANOVA in general linear models by SPSS 13.0 for windows.The results showed that:The three rodent species were significantly different in SL,SW,GBS,FL,RBCL,RSL,RSW and RFL.SL,SW and GBS of Cricetulus barabensis were smaller than other two species.Tscherskia triton had dumpy skull according as the ratio of skull length and skull width was smallest among the three species.Male and female were different in SL,SW,RSW and RFL.Males were larger than female in many parameters of skull relative size.Species and sex factors had interaction effect on SL,GBS,GBS/SW and BCL/SW.The observed differences of skull size and shape among the three species and between genders can be used to distinguish the species and gender.
