Towards the end of 2016, the NNBF acquired EthoVision™ software and the DanioVision™ system from Noldus® – a company that has had great success in developing software and instruments for behavioural research. By adding these systems to our infrastructure, we are now able to measure a range of behavioural parameters (swimming speed and distance, spacial preference, mobility time, etc.) in zebrafish in a controlled environment and observe up to 96 larvae (or other small organisms, e.g. insects, daphnia and tadpoles) simultaneously in the DanioVision system.
Figure 1: Danio rerio (7dps) showing a track for a two minute swimming interval using the DanioVision.
The big advantage of this new infrastructure is that all observation/ scoring is automated and allows for a high throughput – thereby enabling us to use the system as a screening tool during exposure studies. After planning an experimental setup and getting acquainted with the software and new equipment, we were able to perform the some initial experiments, generating enormous amounts of data – the system thereby proving itself extremely valuable and more than capable of quickly and efficiently analysing complex zebrafish behaviour – something that in the past could have taken many man hours, with some parameters being close to impossible to score by the naked eye.
Figure 2: The arena settings and calibration of the physical setup within our behavioural room.
The software tracks behaviour by distinguishing the movements made by an animal subject from a static background, thereby generating frame-to-frame co-ordinates of the subject’s whereabouts. Afterwards, these co-ordinates are used to calculate the chosen parameters and visualize data in a range of formats, including heat maps and movement paths. Thus far the video tracking system has proven to be a very valuable new addition to our current infrastructure providing an additional platform to extend our findings based on toxicity data to a behavioural paradigm.
Figure 3: An example of the pathway of movement which is quantified using EthoVision™ .