Impact of digital video analytics on accuracy of chemobehavioural phenotyping in aquatic toxicology

Abstract

Chemobehavioural phenotypic analysis using small aquatic model organisms is becoming an important toolbox in aquatic ecotoxicology and neuroactive drug discovery. The analysis of the organisms’ behavior is usually performed by combining digital video recording with animal tracking software. This software detects the organisms in the video frames, and reconstructs their movement trajectory using image processing algorithms. In this work we investigated the impact of video file characteristics, video optimization techniques and differences in animal tracking algorithms on the accuracy of quantitative neurobehavioural endpoints. We employed larval stages of a free-swimming euryhaline crustacean Artemia franciscana,commonly used for marine ecotoxicity testing, as a proxy modelto assess the effects of video analytics on quantitative behavioural parameters. We evaluated parameters such as data processing speed, tracking precision, capability to perform high-throughput batch processing of video files. Using a model toxicant the software algorithms were also finally benchmarked against one another. Our data indicates that variability in video file parameters; such as resolution, frame rate, file containers types, codecs and compression levels, can be a source of experimental biases in behavioural analysis. Similarly, the variability in data outputs between different tracking algorithms should be taken into account when designing standardized behavioral experiments and conducting chemobehavioural phenotyping.

An Engineered sgsh Mutant Zebrafish Recapitulates Molecular and Behavioural Pathobiology of Sanfilippo Syndrome A/MPS IIIA

“…While we previously demonstrated the presence of early-life hyperactivity and reduced anxiety by way of a reduced wall preference in the larval and adult sgsh Δex5−6 mutant ( Figure 2 ), we viewed it necessary to determine whether this phenotype could be attenuated by neuroinflammatory rescue. To elucidate the broader phenotypic consequences of amelioration of neuroinflammation in sgsh Δex5−6 larvae, we applied an escape-response test that assessed thigmotactic behaviours under either standard or ‘threatened’ environmental conditions (changes in ambient lighting mimicking the presence of a predator) [ 31 ]. In contrast to previous assays where basal activity (i.e., under unstimulated conditions) was examined, a different approach utilising a simulated adverse stimulus is necessary.…”

“…For analysis of behavioural data, a standardised method was used [ 31 ]. Video files were post-processed using DaVinci Resolve 15 (BlackMagic Design, Australia) video editing software.…”

“…Pathology in the CNS of Homozygous sgsh ∆ex5−6 Zebrafish Recapitulates Features of Human MPS IIIA As hyperactivity and other abnormal behaviours are characteristic of early stages of MPS IIIA pathology, wild type and sgsh ∆ex5−6 homozygous larvae were assayed at 5 dpf (roughly comparable to early childhood in humans) for activity using a custom, video-based behavioural tracking system [31]. Neural development occurs rapidly in zebrafish and is largely complete by 5 dpf; this is therefore an appropriate time point at which to assay early-life behaviours.…”

Epinephrine May Contribute to the Persistence of Traumatic Memories in a Post-traumatic Stress Disorder Animal Model

“…Each animal was placed in the corner of the arena and locomotor activity was recorded for 10 min with a digital video camera Sony HDR-CX405 (Sony Corporation, Japan). The total distance traveled was analyzed using ToxTrac ver 2.84 (open source software freely available at sourceforge.net/projects/toxtrac, Rodriguez et al, 2017Rodriguez et al, , 2018Henry et al, 2019). The number of squares crossed, entries in the center, and feces were analyzed manually and blinded.…”

Treatment With Nepicastat Decreases Contextual Traumatic Memories Persistence in Post-traumatic Stress Disorder

“…Each animal was placed in the corner of the arena and the number of squares crossed, entries in the center, and feces were recorded for 10 min with a digital video camera Sony HDR-CX405 (Sony Corporation, Japan) and analyzed manually and blinded. The total distance traveled was recorded and analyzed using ToxTrac ver 2.84 1 (Rodriguez et al, 2017(Rodriguez et al, , 2018Henry et al, 2019).…”