Department of Animal Physiology, University of Bayreuth, Bayreuth, Germany
In order to analyze the spatial behaviour of young Guinea pigs under different social conditions, a method was developed which allows both a simple acquisition, as well as a simple analysis of spatial data of the observed animals. This method fulfils three functions: 1. the specification of the animals activity, 2. the characterization of the social relationships and 3. it allows an explorative analysis of the frequency of spatial position.
The behaviour of the five animals in each group is recorded with a video system for one hour respectively. Thereafter the videos are analyzed with the assistance of the VTA-module of the program The Observer (Noldus Information Technology). Simultaneous with the continuous recording of the behaviour of the respective focus animal, also the spatial position of all animals can be entered as follows: with the help of the notes function of the program, each animal's position inside a grid drawn on the monitor is recorded every 60 s according to the instantaneous sampling method.
The spatial data are evaluated with the assistance of a spreadsheet which was programmed specially for that purpose in the program Excel (Microsoft). The following variables are calculated from the spatial data:
1. for the determination of activity:
- the mean distance the animal traveled per interval
- the overall traveled distance
2. for the characterization of the social relationships within the group, particularly mother-infant attachment:
- the mean distance between each of the five animals
- the nearest neighbour at each point in time and the respective distance to it
- the frequencies at which each other animal approached one another or avoided one another
- a coefficient that (according to Hinde) indicates which animal of a dyad is responsible for the proximity to another
3. for the explorative analysis of space use and position preference:
- the frequency of spatial position of each animal, both in 2-dimensional and in 3-dimensional figures
- the time sequence of the changes of location of the animals in a 2-d graph of the enclosure
By this usage of spreadsheet programs in combination with conventional ethological software also non-programmers are enabled to develop tools for behavioural analysis, within a short time, which are both simple to handle as well as flexible enough for explorative procedures.