MLE11_MLE06_presentation_2022-09-01_14-10-58_0000214

Rats were purchased from Janvier Laboratories at 6 weeks of age. Upon arrival, rats were housed in pairs that were conserved throughout the experiment. After one week of acclimation, we identified each individual with a subcutaneous Radio Frequency Identification (RFID) tag (APT12 PIT tags; Biomark, Inc., Boise, The United States of America) inserted under gas anaesthesia (Isoflurane) with local analgesia (Lidor 20 mg/ml, with 40μl/10g). RFID tags were positioned in the lower part of the left flank. Rats were allowed to recover for at least ten days. We recorded dyadic interactions between two unfamiliar male rats of the same age (12–14 weeks of age). The focal animal encountered an unfamiliar animal of the same sex for one hour, in the LRT setup, with bedding. Light is diminished to 26 lux (within the cage). The two animals are left undisturbed for one hour. We coupled the Live Rat Tracker (LRT) system (https://micecraft. org/lmt; version 931) with the Avisoft Ultrasound Gate 416 (300kHz sampling rate, 16-bit format; trigger: level of this channel; pre-trigger: 1s; hold time: 1s; duration: >0.005s; trigger event: 2% energy in 25–125kHz with entropy <50%; Avisoft Bioacoustics, Glienecke, Germany) connected to a CM16/CMPA microphone (Avisoft Bioacoustics, Glienecke, Germany). LRT and Avisoft systems were synchronised.实验大鼠购自詹维尔实验室（Janvier Laboratories），购时为6周龄。抵达后，大鼠以成对方式饲养，且整个实验期间维持该饲养组合不变。适应一周后，我们通过皮下植入式射频识别（Radio Frequency Identification，RFID）标签（型号APT12 PIT标签；Biomark公司，美国博伊西）对每只大鼠进行个体标识，植入操作采用异氟烷（Isoflurane）吸入麻醉联合局部镇痛（使用20mg/ml的Lidor，剂量为40μl/10g体重）。RFID标签植入于大鼠左侧腹下部。大鼠术后至少恢复十日。本研究记录了两只同周龄（12~14周龄）的陌生雄性大鼠之间的成对互动行为。实验采用活体大鼠追踪器（Live Rat Tracker, LRT）装置，将一只目标大鼠与一只同性陌生大鼠置于铺有垫料的笼盒中，互动时长为1小时；笼内光照强度降至26勒克斯（lux）。期间不对两只大鼠进行任何干扰。我们将活体大鼠追踪器（LRT）系统（版本号931，官网链接：https://micecraft.org/lmt）与Avisoft Ultrasound Gate 416超声采集设备相连，该设备采样率为300kHz，采用16位采样格式，触发参数设置为：通道电平触发，预触发时长1秒，保持时长1秒，有效时长>0.005秒；触发事件为25~125kHz频段内能量占比2%且熵值<50%。该超声设备连接有CM16/CMPA型麦克风，均产自德国格利内克的Avisoft Bioacoustics公司。LRT系统与Avisoft超声采集系统实现同步。