Correlação entre perfil comportamental e eclosão em zebrafish

Abstract

Individuals in the same population can differ in several ways. In previous studies, we observed that in fish, individuals that were born earlier show more active behavior and are more exploratory than those that were born later, a characteristic of behavioral syndrome. One of the aspects relevant to the theory is the consistency of behavioral differences between contexts and over time. Thus, the present study evaluated the relationship between incubation time and behavioral consistency in two ontogenetic stages and in different contexts in zebrafish (Danio rerio). For this, the animals were separated according to the incubation time in early emerging (EE) and late emerging (LE) and tested in a risk-taking context (light x dark tank) at the 30th day post fertilization (dpf) and at the 120th dpf. The animals were also tested in the novel tank and novelty assessment contexts. In the risk-taking test, EE animals presented shorter latency to take risks and stayed longer in the risky area compared to LE animals. In the novel tank and novelty assessment tests, the EE individuals were more exploratory and showed less anxietylike behavior than the LE. In general, the results obtained suggest that the incubation time may indicate consistent differences in behavioral profile in zebrafish, corroborating the pace-of-life theory.