Behavior Responses Of Zebrafish Under Environment Stress In The Persistence Model

In this thesis,experiments on the behavior responses of zebrafish under normal conditions,organic pollutants(ATZ,DBP,DDT,and DM),and inorganic pollutants(ammonia nitrogen,cadmium,and thallium)stress conditions were conducted.Based on the behavior responses of zebrafish under normal conditions,between normal conditions and pollutant stress,between different concentrations of the same type of pollutants,and between different types of pollutants were analyzed individually and comparatively based on the zebrafish behavior strength,and the behavior dynamic responses of zebrafish due to the survival adaptive capacity and tolerance capacity of zebrafish under pollutant stress were summarized.To further clarify zebrafish behavior patterns and discuss the behavior responses of zebrafish adhering to the model under environmental stress,the following conclusions were obtained.1.The inhibition of zebrafish behavior strength under environment stress.In the control group,the values of zebrafish behavior strength were 0.73±0.13,0.66±0.14 and 0.69±0.13 for light periods,dark periods and the whole experiment.According to the average behavior strength values zebrafish under organic pollutant stress and the average behavior strength values zebrafish under inorganic pollutant stress,the inhibition phenomenon was obvious in all experimental groups,in which 0.02 mg/L deltamethrin and 0.01 mg/L cadmium were more significantly inhibited than(P<0.001)than the other experimental groups.And the degree of inhibition of behavior strength was related to the stress conditions,and the two showed positive correlation within a certain range.According to the the AV zebrafish under organic pollutant stress,the variation of behavior strength during the light and dark periods in the control group was relatively stable and remained around 10%,while the degree of diurnal variation of behavioral intensity in zebrafish under pollutant stress fluctuated more sharply than that in the control group,with the extreme value of variation reaching 31.91%.2.There was a clear circadian rhythm in the behavior responses of zebrafish in all conditions of the experiment.The peak of positive and negative correlations in the autocorrelation analysis appeared periodically and showed a good symmetry in general,reflecting the characteristics of a cycle with 24 h.However,due to the influence of environment stress,the time nodes of the circadian rhythm phenomenon were disturbed,and the distribution of behavioral intensity in the SOM clustering analysis also showed some abnormal distribution,and the clusters with dark cycle showed red parts with higher behavioral intensity,which reflected the disturbance of circadian rhythm cycle.3.The behavior responses patterns of zebrafish under environmental stress mainly include no-effect pattern,stimulation pattern(Ms),adaptation pattern(Mac),regulation pattern(Maj),and toxic effect pattern(Mte).The analysis of the dynamic equilibrium characteristics of the process from behavior mode Ms to Mac to Maj is important for the study.Under normal environmental conditions,when water quality remains constant,zebrafish behavior may not change and Bn(normal behavior)is the dominant mode.Under environmental change conditions,water quality starts to decline,which may trigger the behavioral pattern of Bn to Bp,the behavior of fish will change,once the behavior pattern reaches the threshold switch,the fish will start its resistance ability and the change of Bn to Bp will occur,which is used to cope with environmental stress,after a period of time,the transformation of Bp to Bn will occur,and a dynamic equilibrium will be reached between the transformation of Bn and Bp and the external environment.The behavior responses of zebrafish under environment stress shows a no-effect phase at first,and with the continuous extension of the stress time,zebrafish will experience behaviors after perceiving the environmental stress,and the termination of these states is the first environmental stress threshold,which is the maximum tolerance of zebrafish itself to resist the environment.After the first environmental stress threshold is experienced by the fish,the conversion of Bn to Bp is gradually accelerated and the intensity of the behavior sharply decreases in order to adapt to the increasing environmental stress,switching from the stimulation mode(Ms)to the adaptive regulation mode(Mac).Under continuous environment stress,the switch from the adaptive regulation mode(Mac)to the re-regulation mode(Maj)was made to adapt to the increasing environmental stress.In summary,the results of this thesis show that the dynamic response of fish behavior due to survival adaptability and tolerance capacity of zebrafish under environment stress was summarized based on the analysis of zebrafish behavior strength data in the online biomonitoring systems in various environment stress experiments with a period of 360 h.The behavior pattern of zebrafish and the behavior responses of zebrafish under environmental stress in the adherence model were further clarified for providing data basis for monitoring water quality changes,water quality assessment and early warning.