Behavioral response of Zebrafish Danio rerio Hamilton 1822 to sublethal stress by sodium hypochlorite: ecotoxicological assay using an image analysis biomonitoring system

Abstract

We evaluated behavioral responses of zebrafish Danio rerio exposed to sublethal concentrations of sodium hypochlorite using an image analysis biomonitoring system (IABS). First, the limits of normal variation in swimming activity of zebrafish were determined by monitoring traveled distance of 40 control fishes using the IABS. An acute toxicity test was performed to determine the LC(50(24 h)) for D. rerio to NaOCl. To evaluate the toxic effects in swimming activity, 32 fishes were exposed to 40%, 30%, 20%, 10% of the LC(50 )and 32 were used as control using the IABS. We considered toxic concentrations where more than 10% intervals of the treated group were below the limits of normal variation and were significantly different from the control group. Two main responses were observed: an escape response (increased swimming activity) at 10% treated group, a gradual decrease in swimming activity from the 20% of the LC(50) on, and an avoidance response at higher concentrations. The response of the 20% treated group were considered as a NOAEL and responses of the 30% and 40% treated groups indicated significant hypoactivity (adverse effect). This behavioral biomonitoring system has proven to be a useful tool to detect sublethal toxicity that could be incorporated in biomonitoring protocols in Brazil.

A novel computational approach of image analysis to quantify behavioural response to heat shock in Chironomus Ramosus larvae (Diptera: Chironomidae)

“…Moreover, this video image analyser would be suitable for tracking trajectory of locomotor behaviour and not for analysis of single harmonic motion as displayed by a midge larva described in this paper. Magalhäes et al (2007) reported a system of behavioural responses in zebrafi sh to chemical toxicity caused due to sodium hypochlorite using an image analysis system. Th e alteration of swimming activity could be detected by the biomonitoring system.…”

Resilience assessment of a biological early warning system based on the locomotor behavior of zebrafish (Danio rerio)

“…They were the most informative for the SOM model since they presented all the necessary information regarding the fish's location in the arenas (X and Y coordinates) and their overall locomotor activity (all other endpoints). Also, they are extensively used by other authors in other assays with zebrafish (Brewer et al, 2001;Chen et al, 2011;Chon et al, 2005;Liu et al, 2011;Magalhães et al, 2007), and in these works, the systems were capable of detecting behavioral changes such as erratic movement, freezing, hyperactivity, or hypoactivity. Analyzing in ensemble, all the information about the locomotor behavior of the fish, the SOM model was able to classify the behavior in each frame and assign a behavior category, with a precision, that would never be possible to achieve if the behavior parameters were analyzed individually.…”

“…The selected toxicants are ecologically relevant, belonging to different chemical groups and having different mechanisms of action. They are capable of causing behavioral changes in zebrafish (Gerlai et al, 2000;Gerlai et al, 2006;Magalhães et al, 2007;Nimkerdphol and Nakagawa, 2008;Saili et al, 2012;Wang et al, 2013), have known values of 96 h LC 50 , and high to moderate solubility in water.…”

Analysis of Individual Versus Group Behavior of Zebrafish: a Model Using pH Sublethal Effects

“…To evaluate the behavioral responses in swimming, an image analysis biomonitoring system (IABS) was used (Magalhães et al 2007). A digital camera captured images and they were analyzed with a Videomex-V (columbus instruments) as white pixels over a black background using the software traveled distance of multiple objects (TDMO) to register the mean swimming velocity of each fish.…”