6.The trace element content in unripe semen Areca has obvious difference compared with matured semen Areca. Pb content of the unripe semen Areca is 2. 21× 10-6 which is twenty times the Pb content of matured semen Areca.
7.According to the records of semen collection of South Devon bull from 1999 to 2002, fresh semen volume, density, activity and frozen semen activity data were summed up, and semen quality of South Devon bull was compared between different seasons and years.
