Method of tracking a plurality of objects

A method of tracking a plurality of objects, wherein the objects are nematode worms, comprising:

• focusing an image of the objects on an imaging element using an optical system;
• capturing image frames of the objects using the imaging element comprising a plurality of pixels;
• measuring at least one characteristic of the objects from the captured image using an image processor;
• wherein a field of view of the optical system is set to be the widest field of view for which the image processor is able to measure the at least one characteristic, and the field of view is determined based on the average size of the objects and a predefined minimum resolution required for the image processor to measure the at least one characteristic;
• and
• wherein the at least one characteristic comprises one or more of:
• bends per minute, bending amplitude, length, translational speed and paralysis rate.