[Changes of Serum Gonadal Hormones Levels During Musk-secreting Period and Estrus of Moschus berezovskii].

Objective: To detect concentrations of serum gonadal hormones (testosterone, estradiol and progesterone) in musk-secreting period and estrus of Moschus berezovskii, and to study the association of serum gonadal hormones concentrations and musk-secreting.

Methods: The concentrations of serum gonadal hormones were detected with magnetic particle separation ELISA.

Results: During musk-secreting period, concentration changes of three serum gonadal hormones showed clear regularity, three crests occurred synchronously.

[Growth process of Larix principis-rupprechtii stands with different density on south slope of Liupan Mountains].

By the method of sample trees stem analysis, this paper studied the growth process and diameter structure of 21-year-old Larix principis-rupprechtii plantations with the densities of 1200, 1500, and 2000 stems x hm(-2) in the head-water area on the southern slope of Liupan Mountain in Ningxia Hui Autonomous Region. The results showed that there were no significant differences in the growth status of L. principis-rupprechtii stands among the three densities when the stand age was less than 10 years.