Prey capture assay for zebrafish larvae ~ The lighting system

To understand how a sensory input leads to a particular behavioral output, we are studying prey capture behavior in zebrafish larvae. First, we would like to describe the behavior in a quantitative manner using several parameters (position, swimming speed, approach to prey, eye convergence, etc.). These parameters may be obtained automatically by image processing. For a successful image processing, lighting condition is a critical issue.

 

Here are some tricks that make it possible to isolate zebrafish larval eyes and paramecia from the background.

IMG_0753_LEDforParameciumCaptureAssay

I came to this solution after a bit of trial and error.

IMG_0754_LightingSysetmForPreyCaptureAssay

This is a darkfield illumination but the background is not too dark.

IMG_0761_ZebrafishLarvaInRecordingChamber

So, the paramecia appear in white and the zebrafish larval eyes appear in black on the gray background.

20150818_163650_2385-2406CropAnimGif

Uniform background and enough contrast for both the zebrafish larva and paramecia.

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