Zebrafish (Danio rerio) has been more widely used to study pharmacology. Oxytectracycline (OTC) is a broad-spectrum antibiotic and works by interfering with the ability to produce essential proteins of bacteria. The aim of this study was to identify the effects of exposure to OTC on behavioral changes or endocrine response in zebrafish. The behavioral effects of exposure to OTC (50, 100 or 200 mg/l) were characterized in several novelty-based paradigms such as the novel tank or open field test in zebrafish. Moreover, to investigate effects of exposure to OTC on endocrine response, we measured whole-body cortisol level using cortisol ELISA kit. As results of novel tank test, duration in top and immobile duration were significantly increased by the exposure to OTC in a concentration-dependent manner (p<0.05). In addition, moving distance, highly mobile, velocity and zone transition were significantly decreased by the exposure to OTC in a concentration-dependent manner (p<0.05). As results of open field test, the exposure to OTC increased immobile duration significantly (p<0.05). However, moving distance, mobile duration and velocity were significantly decreased by the exposure to OTC in a concentration-dependent manner (p<0.05). Besides, the exposure to OTC elevated whole-body cortisol levels in zebrafish. These results suggest that the exposure to OTC may induce chemical stress in zebrafish.

This research is the follow-up study of Hwang & Ko (2018), in which five different motivational profiles are identified. Considering students with negative motivational constructs (profiles 1 and 2 in Hwang & Ko, 2018) have high potential to perceive them as students who give up on learning mathematics, we examined parents’ education levels, how to do homework and extra lessons, home resources, sense of school belonging, student bullying, and achievement by motivational profile with descriptive statistics, tests, and ANOVA. The findings showed that students would avoid learning mathematics if they have limited home resources while they want to improve their achievement. However, having enough home resources is not enough. If students are not able to see the improvement in their achievement despite their efforts to take extra lessons and spend their home resources, they would also be students who give up on learning mathematics potentially.