Azabu University 2 articles published in JoVE Developmental Biology Isolation of Murine Spermatogenic Cells using a Violet-Excited Cell-Permeable DNA Binding Dye Yu-Han Yeh*1,2, Mengwen Hu*1,2, Toshinori Nakagawa3,4, Akihiko Sakashita1,2, Shosei Yoshida3,4, So Maezawa5,6, Satoshi H. Namekawa1,2 1 Here we present a simple and efficient method to isolate live meiotic and post-meiotic germ cells from adult mouse testes. Using a low-cytotoxicity, violet-excited DNA binding dye and fluorescence-activated cell sorting, one can isolate highly enriched spermatogenic cell populations for many downstream applications. Behavior Determining Ultrasonic Vocalization Preferences in Mice using a Two-choice Playback Test Akari Asaba1, Masahiro Kato3, Nobuyoshi Koshida2, Takefumi Kikusui1 1School of Veterinary Medicine, Azabu University, 2Division of Electric and Information Engineering, Tokyo University of Agriculture and Technology, 3Kato Acoustics Consulting Office Ultrasonic vocalizations (USVs) in mice differ depending on age, sex, condition, and genetic background. Using two ultrasound emitters broadcasting simultaneously in different locations, this two-choice test can evaluate murine recognition and preference responses to different characteristics of USVs.