Project protocol - Contents

• Workflow and sampling
• Equipment and supplies
• Reagents and solutions
• Procedure: Study 1: Interaction for resident/intruder pairs
• Procedure: Study 2: Interaction for simultaneously added pairs
• Data

Workflow and sampling

Step	Procedure	Equipment	Data collected
1	Study 1: 20 min intra-strain test designed to elicit all types of social interactions (between resident and intruder)	Clear polypropylene cage equipped with video camera	Social behaviors
2	Study 2: 30 min intra-strain test designed to reduce the number of aggressive behaviors (both mice put in cage simultaneously)	Clear polypropylene cage equipped with video camera	Social behaviors

Equipment and supplies

• Test chamber: Clear polypropylene cage (27.5 x 15.5 x 13.0 cm) with bedding covering the bottom
• Video camera: Panasonic VHS

Reagents and solutions

• Cleaning solution

Procedure: Study 1: Interaction for resident/intruder pairs (cohort 1)

1. One male mouse is placed in the cage and allowed to explore freely for 15 min (resident).
2. A second male mouse of the same strain is added to the cage (intruder).
3. Behavior is recorded for 20 min.
4. Videotape is reviewed by a naive observer and behavior scored for each pair of mice.
5. Note: At the end of a session, both mice are removed from the chamber, and the chamber is cleaned and new bedding added before the next pair of mice is tested.

Procedure: Study 2: Interaction for simultaneously added pairs (cohort 2)

1. Both mice of the same strain are added to the chamber simultaneously.
2. Behavior is recorded for 30 min.
3. Videotape is reviewed by a naive observer and behavior scored for each pair of mice.
4. Note: At the end of a session, both mice are removed from the chamber, and the chamber is cleaned and new bedding added before the next pair of mice is tested.

Data collected by investigator

• Study 1
  • Mounting
  • Wrestling
  • *Allogrooming (not observed for any pair of mice)
  • *Barbering (not observed for any pair of mice)
  • *Huddling (not observed for any pair of mice)
  • Following
  • *Butt sniffing (observed for all pairs of mice)
  • *Face sniffing (observed for all pairs of mice)
  • Total time spent in social behavior
• Study 2
  • Number of sniffs
  • Time spent sniffing
  • Number of negative social interactions
  • Time spent engaged in negative social interactions
  • Number of positive social interactions
  • Time spent engaged in positive social interactions
  • *Number of mounts (one 129S1/SvImJ mouse was observed mounting)
  • Time spent engaged in mounting behavior
  • Time engaged in any type of social behavior

Measures marked with * were the same for all mice tested except where noted. These measures were not accessioned. All submitted data are available in the download file.

Percentages computed by MPD