Locomotor Activity Of Fish Research Articles

Phenytoin causes behavioral abnormalities and suppresses kisspeptin expression, reducing reproductive performance in Japanese medaka

Phenytoin, an antiepileptic drug, induces neurotoxicity and abnormal embryonic development and reduces spontaneous locomotor activity in fish. However, its effects on other endpoints remain unclear. Therefore, we investigated the effects of phenytoin on the swimming behavior and reproductive ability of Japanese medaka. Abnormalities in swimming behavior, such as imbalance, rotation, rollover, and vertical swimming, were observed. However, when phenytoin exposure was discontinued, the behavioral abnormality rates decreased. Phenytoin exposure also significantly reduced reproductive ability. By investigating reproduction-related gene expression of gnrh1, gnrh2, fshb, and lhb remained unchanged in males and females. In contrast, kiss1 expression was significantly suppressed due to phenytoin exposure in males and females. kiss2 expression was also significantly suppressed in females but not in males. We filmed videos to examine phenytoin exposure effects on sexual behavior. Females showed no interest in the male's courtship. As the kisspeptin 1 system controls sexual behavior in Japanese medaka, phenytoin exposure may have decreased kiss1 expression, which decreased female reproductive motivation; hence, they did not spawn eggs. This is the first study to show that phenytoin exposure induces behavioral abnormalities, and suppresses kiss1 expression and reproductive performance in Japanese medaka.

Spatial distribution and circadian locomotor activity of invasive armored catfish (Loricariidae) in the freshwater and brackish water.

Invasive suckermouth armored catfish Pterygoplichthys spp. successfully spread during one decade into many river systems of Vietnam. Wide and rapid invasion of armored catfish might be associated with using brackish water in estuaries to spread from one river system to another. The first goal of our study was to assess the horizontal and vertical distribution of invasive fish in freshwater (Da Rang River) and in brackish water (Da Rang River estuary) associated with circadian rhythm. In the both sampling locations, fish were mainly caught at nighttime at the bottom and near the surface using the net traps and vertical nets. In estuary, fish were caught in the net traps with distance 2.0-7.5 m from the right or left banks where water was predominantly fresh. In freshwater of the Da Rang River, fish were often caught near the left bank with gravel and stone substrate. The second goal of our study was to experimentally evaluate the circadian (12 hours of the night and 12 hours of the day) rhythm of locomotor activity (LA) of fish. Fish from different freshwater locations (Am Chua canal and Da Rang River) had a similar diurnal dynamic of LA with mostly movements (77-83% of total diurnal LA) at nighttime (18:00-6:00, GMT+7) at the end of the wet season. Armored catfish from the brackish water location (Da Rang River estuary) also were mostly active (76% of total diurnal LA) overnight. However, fish from freshwater and brackish water had difference in the timing of behavioral activity. Fish LA from estuary was significantly lower than LA of fish from freshwater locations during 18:00 to 21:00 before low tide. The results of our field and experimental studies established that armored catfish in estuary moved in horizontal and vertical planes predominantly at nighttime. Tide level regulates locomotor activity of invasive fish and could influence on the possibility of their spreading through the estuary.

Effets of Antihistamines in Adult Zebrafish in Novel Tank Test

Histamine receptors play pivotal roles in various physiological functions, ranging from allergic responses to memory and sleep regulation, making them important drug targets. While second-generation antihistamines have been successfully used in rodents and humans, investigating their effects in non-traditional animal models enhances our understanding and aids the development of novel drug candidates. In this study, we examined the impact of the first-generation drug chloropyramine and the second-generation drugs loratadine and cetirizine, at concentrations of 1, 5, and 10 mg/L, on adult zebrafish b-ehavior using the novel tank test. All three drugs significantly altered fish locomotor a-ctivity, decreasing distance traveled and average velocity while increasing low acceleration frequency. Chloropyramine at 5 and 10 mg/L and loratadine at 1, 5, and 10 mg/L significantly reduced top entries compared to the control. Additionally, 5 mg/L chloropyramine increased the total duration of top entries, whereas loratadine at 10 mg/L r-educed this behavior compared to controls. Overall, chloropyramine and loratadine e-xhibited a sedative effect typical of antihistamines, while cetirizine solely reduced locomotor activity without affecting other patterns of fish behavior. Thus, cetirizine demonstrated the least impact on the central nervous system among the studied drugs, making it the optimal and safest choice among antihistamines.

MOVEMENT ACTIVITY OF ROUND GOBY (NEOGOBIUS MELANOSTOMUS PALLAS, 1814) UNDER THE INFLUENCE OF GEOMAGNETIC FIELDS

Introduction. Behavioral traits of fish are an important manifestation of their response to external stimuli. Locomotor activity reflects the influence of specific factors on fish behavior and the role they play in their lives. Among the least studied factors are fluctuations in the geomagnetic field and their impact on the locomotor activity of the round goby Neogobius melanostomus Pallas, 1814. Aim. The aim of this study was to investigate the influence of fluctuations in the geomagnetic field on the locomotor activity of the commercially important speciesof benthic ichthyofauna, the round goby Neogobius melanostomus Pallas, 1814, in the Black Sea. Methods. The ichthyological material was collected in the coastal waters of the Odesa Bay, ranging from Cape Northern Odesa to Cape Velikyi Fontan, during a scientific research survey conducted by the I.I. Mechnikov Odesa National University (ONU). Laboratory investigations were conducted in the aquarium room of the Aquatic Biology and General Ecology Department of the I.I. Mechnikov Odesa National University. Hourly changes in fish locomotor activity were recorded and analyzed as a result of the study. During the specified observation period, periods of increased geomagnetic activity were identified and compared to periods when this activity was within normal range. An original methodology called “Computer Vision Method” was employed for processing the visual data and tracking of the laboratory animals. Results. The maximum values of geomagnetic activity during the observation period, classified as a first intensity magnetic storm of class G1, were observed on February 3, 2022, from 6 to 12 hours, and on February 4 and 10, 2022, from 15 to 21 hours. When comparing the levels of fish locomotor activity during these time intervals with their activity during the time intervals on days with minimal geomagnetic activity (February 8, 9, and 15, 2022), a decrease in locomotor activity of individuals during magnetic storms of 27% to 42% can be observed. Conclusion. The fluctuations in locomotor activity of the round goby during increased geomagnetic activity up to the level of magnetic storms indicate the ability of this species to perceive magnetic fields and respond to changes in its properties. Specifically, when the Kp-index values corresponded to a first intensity geomagnetic storm (G1), a decrease in fish locomotor activity was observed compared to the activity during the same time intervals on days with minimal geomagnetic activity.

Features of movements of climbing perch Anabas testudineus in water flow and on land

Climbing perch Anabas testudineus in contradistinction to most fish is able to move not only in water but also on land. In the experiments, we study the diurnal locomotor activity of fish, the features of their movements in flow of clean water and polluted water by urea and thiourea, and the effect of decreasing water level on the crawling and moving on land. The behavior of fish in clean water aimed to move downstream at the beginning of the test and moving upstream in the end of the test. Fish exposition (12 days) under 0.05% urea and thiourea change their behavior in the water flow, which is expressed in the chaotic movement of fish relative to the current. Decreasing water level to the critical value (<3 cm) initiates climbing perch to crawling and moving on land. Two types of fish responses to decreasing water level were found: waiting, or crawling to land and moving. Based on the study diurnal locomotor activity, we found that the probability of climbing perch movements is higher in the daytime than in the dark.

Toxicological assessment of cadmium-containing quantum dots in developing zebrafish: Physiological performance and neurobehavioral responses.

The present research investigated the effects of exposure to sublethal concentrations of cadmium selenide/zinc sulfide (CdSecore/ZnSshell)-containing quantum dots (QDs; 0 - 100µg/L QDs) on the neurophysiological performance of developing zebrafish (Danio rerio). The results suggested that exposure to CdSe QDs for 5 days increased the whole-body content of Cd without affecting the general physiological conditions of larvae. Interestingly, CdSe QD exposure reduced swimming distance but increased swimming velocity of larvae, suggesting that the exposure may lead to burst/episodic swimming. The findings also suggested that CdSe QD exposure reduced the wall-hugging behavior of larvae during a sudden light-to-dark transition test, and that the exposure significantly decreased the locomotor activity of fish during the dark period. On the other hand, control larvae displayed a dark avoidance behavior, whereas CdSe QD-exposed larvae exhibited an increase in the time spent in the dark zone, providing further support that CdSe QDs inhibited anxiety-related responses in larvae. Additional analysis with droplet digital PCR revealed that CdSe QD exposure altered the mRNA levels of genes that are associated with dopamine signaling and oxidative stress response. Collectively, our findings suggested that CdSe QD exposure may induce neurobehavioural toxicity and alters the mRNA abundance of dopamine- and oxidative stress-related genes in developing animals.

Investigating mitochondria-immune responses in zebrafish, Danio rerio (Hamilton, 1822): A case study with the herbicide dinoseb

The dinitrophenol herbicide dinoseb is an uncoupler of mitochondrial oxidative phosphorylation (OXPHOS). Studies in fish demonstrate impaired OXPHOS is associated with altered immune system responses and locomotor activity in fish. The objective of this study was to determine the effect of dinoseb on zebrafish (Danio rerio) during early stages of development. We measured oxygen consumption rates of embryos, transcripts related to OXPHOS, growth, and the immune system (cytokines and immune-signaling transcripts), and locomotor activity. We hypothesized that OXPHOS of fish would be impaired in vivo, leading to altered basal immune system expression and locomotor activity. Oxidative respiration assessments in embryos revealed that dinoseb decreased both mean basal respiration and oligomycin-induced ATP-linked respiration. Expression levels of cytochrome c oxidase complex IV, 3-hydroxyacyl-COA dehydrogenase and superoxide dismutase 1 were decreased in larvae following exposure to dinoseb while succinate dehydrogenase complex flavoprotein subunit A, insulin growth factor 1 (igf1) and igf2a mRNA were increased in abundance. Immune-related transcripts chemokine (C-X-C motif) ligand 1 and matrix metallopeptidase 9 (MMP-9) were decreased in expression levels while toll-like receptor 5a and 5b were increased in expression. In addition, a visual motor response test was conducted on both 6 and 7 dpf larvae to determine if dinoseb impaired locomotor activity. Dinoseb decreased locomotor activity in 7 dpf larvae but not 6 dpf. This study improves knowledge of toxicity mechanisms for dinoseb in early stages of fish development and demonstrates that mitochondrial toxicants may disrupt immune signaling in zebrafish.

Risks to aquatic environments posed by 14 pharmaceuticals as illustrated by their effects on zebrafish behaviour

The presence of pharmaceutical residues in aquatic ecosystems is a worldwide problem that may pose serious threats and challenges to the environment, especially to the safety of aquatic biota. In the present study, we investigated the effects of 14 environmentally relevant pharmaceutical compounds on individual and collective-related behaviours in juvenile zebrafish (Danio rerio) for 21 days. The tested concentrations of the compounds spanned three orders of magnitude. This study also compared the potential risks of these compounds in Chinese surface waters based on the data on their toxic effects or only on behavioural effects. In the case of individual behaviours, most antidepressants, but not anti-inflammatory agents or blood lipid-lowering agents, decreased fish locomotor activity (LMA) and individual social activity (IDS); however, all three classes of compounds induced significant disruptions in the light/dark transition locomotor response (LMR-L/D) performance, even at lower treatment levels (0.1–1 μg/L). Furthermore, collective behaviour (CLB) analysis suggested that most of the compounds significantly altered the group sociability of fish and frequently occurred at environmentally relevant concentrations. Finally, a risk assessment suggested that the presence of ibuprofen, fluoxetine, and venlafaxine in the surface waters of China poses a relatively high risk to fish, regardless of the risk ranking based on the data of the toxic or behavioural effects.

Effect of Melatonin on the Processes of Exotrophy in Common Carp Cyprinus carpio

The effect of melatonin on the initial (feeding) and central link (digestion) of exotrophy in juvenile common carp Cyprinus carpio was investigated in parallel for the first time. The effect of intraperitoneal injections of the hormone at a concentration of 100 and 200 ng/g of body weight on locomotor activity and food consumption, as well as on the activity of digestive enzymes in the intestinal mucosa and chyme, was studied. It was shown that five hours after the administration of the hormone, food consumption and the activity of digestive enzymes in the intestinal mucosa decrease, while the locomotor activity of fish and the enzymatic activity of the chyme do not change significantly. Food consumption is significantly (by factor of 2.2) reduced as a result of the administration of the hormone at a dose of 200 ng/g body weight. The level of caseinolytic and hemoglobinolytic activity of peptidases and amylolytic activity of the intestinal mucosa at this dose also decrease significantly: by 27, 54 and 42%, respectively, compared to the control. The injection of melatonin at a dose of 100 ng/g causes a slight decrease in the level of enzymatic activity of the intestinal mucosa. The mechanisms of the effect of melatonin on the processes of exotrophy in fish are discussed.

Synthesis of Quercetin-Metal Complexes, In Vitro and In Silico Anticholinesterase and Antioxidant Evaluation, and In Vivo Toxicological and Anxiolitic Activities.

The level of acetylcholine, a neurotransmitter essential for processing memory and learning, is lower in the brains of patients with Alzheimer's disease due to the higher concentration of the enzyme acetylcholinesterase. The main compounds used for Alzheimer's treatment are acetylcholinesterase inhibitors. Quercetin coordination complexes with the metal ions Cu+2, Zn+2, Ni+2, Co+2, and Fe+2 were synthesized to investigate their potential use against Alzheimer's disease, by evaluating the inhibition of acetylcholinesterase in vitro and in silico, as well as the antioxidant activity, toxicity, and anxiolytic action in the zebrafish (Danio rerio) model. The organic complexes were characterized by UV-Vis and FT-IR. The spectral information suggested that coordination of metals occurs with the carbonyl group and OH linked to the C-3 carbon of quercetin. The quercetin-Fe (QFe) complex presented the best antioxidant and antiacetylcholinesterase actions, and these results were confirmed by molecular docking. In the toxicity and locomotor evaluation, the quercetin molecules and the synthesized complexes, mainly QCu and QZn derivatives, showed the highest degree of inhibition of the fish's locomotor activity, suggesting a possible anxiolytic action. Then, quercetin complexes with metals, mainly with Fe+2, represent valuable compounds and deserve more investigation as promising agents against Alzheimer's disease.

Behavior of Perch Fry Perca fluviatilis (Percidae) in a Heterothermal Environment at Different Levels of Food Availability

Temperature and available food are among the key factors affecting fish during their lifetime. The interaction between foraging and thermoregulatory behavioral responses was studied in experimental conditions using 1+ perch individuals. The behavior of fish was examined in a thermally heterogeneous environment with varying levels of food availability: “excessive” (food objects constituted 20% of the overall fish weight in each compartment of the experimental device), “limited” (3%), and “zero” (0%). The values of the final preferred temperatures revealed in these conditions differed significantly: 26, 24, and 22°С, respectively. In the conditions of excessive food, fish locomotor activity was minimal. The food of juvenile fish consumed over 15 minutes was independent of the number of food objects (20 and 3%) in the experimental device, constituting 14.2 and 15.2% of the fish body weight, respectively. However, fish growth was observed only in the first case, probably due to the higher locomotor activity needed to find and obtain food in the environments with fewer food objects. The data presented may be useful for estimating the dominant forms of behavior of juvenile fish both in experimental and field conditions.

Electrical Activity and Predation in the Clariid Catfish Clarias macrocephalus (Clariidae) Exposed to Varying Illumination

The influence of illumination (light–dark) on electrical emission in a clariid catfish Clarias macrocephalus hunting fast-moving prey (guppies Poecilia reticulata) has been studied. A total of five types of electrical events has been registered, of which monopolar electrical pulses are classified as specialized electrical discharges. Pulses with multiple polarity reversal and long duration are myograms accompanying the locomotor activity of fish. Pulses with noticeable ruggedness, brief pulses, and a series of pulses can be considered intermediate between the two categories of electrical discharges. The emission of electrical discharges occurs mainly in the dark, which corresponds to the daily feeding chronology in clariid catfishes. It has been first shown that catfish can emit all types of electrical events, including specialized discharges, even when a single fish is isolated. The obtained results confirm that clariid catfish belongs to the weakly electric fishes with episodic emission of specialized electrical discharges. The evolutionary pathway of electric fishes from nonelectric ancestral forms with episodic unspecialized emission of nonsynchronized action potentials to forms that emit more and more synchronized action potentials and further to specialized electric fishes, including strongly electric ones and/or those using electrical discharges for location and communication, is discussed.

A novel emotional and cognitive approach to welfare phenotyping in rainbow trout exposed to poor water quality

Recent scientific evidence for fish sentience has stressed the need for novel sentience-based detection tools of fish welfare impairment in commercial farms. In order to mimic a well-characterised stress situation, rainbow trout (Oncorhynchus mykiss) were exposed to poor water quality (hypoxia combined with high ammonia level) for three weeks (stressed group, S) and compared to a non-stressed control group (NS). After a return to water quality standard, emotional responses were assessed in fish subjected to two potentially threatening situations: (i) social isolation in a novel environment and (ii) human presence. In addition, we used an appetitive-conditioning paradigm to determine whether previous chronic deterioration of water quality disturbs cognitive abilities in fish. Spontaneous behaviour in the tanks was also recorded during the environmental challenge as a reference for fish activity. We observed that in S fish, plasma cortisol levels were increased before and after social isolation in a novel environment compared to the plasma cortisol levels in the NS group, despite the absence of a behavioural difference between the two groups. Under deteriorated water quality, fish locomotor activity was globally reduced and this reduction was correlated to increased shoaling behaviour. Farmers can use these first behavioural modifications as a sentinel detector for fish welfare impairment. More importantly, we demonstrated that reactivity to a human presence in a home-environment and food-anticipatory behaviour were both inhibited in the S group. We consider that these two sentience-based tests are highly relevant for fish welfare assessment at the group level and are easy to use in the aquaculture industry.

Rapid Detection of Sublethal Toxicity Using Locomotor Activity of Rainbow Trout Juveniles.

This study examined changes in locomotor activity of the rainbow trout (Oncorhynchus mykiss) juveniles exposed to sublethal concentrations of hexavalent chromium (Cr6+) (as a single pollutant) and landfill leachate (as an complex mixture of mainly organic compounds, including trace amounts of metals). Fish were first examined for baseline behavior patterns for 3h to determine the appropriate duration of acclimation and the control level. The average velocity of fish was found to be the most informative among other endpoints throughout the 3h long acclimation. Under the effect of both test substances, fish locomotor activity significantly increased after 5min reaching maximum values after 10min of exposure. The juveniles exposed to leachate were more responsive than those exposed to Cr6+. However, in this study we did not succeed in identifying pollutants from the elicited fish behavioral response patterns.

Light and dark rations and the photic entrainment of circadian locomotor activity patterns in the South American Silver Catfish (Rhamdia quelen, Quoy & Gaimard, 1824)

The aim of this study was to evaluate the daily rhythm of locomotor activity in Rhamdia quelen (R. quelen). A total of 30 fish were enrolled in the study and were equally divided in 10 groups and maintained in 100 liters tanks. The locomotor activity was measured in fish maintained under the LD 12:12 photoperiod regime; thereafter, the LD cycle was reversed to DL in order to study the resynchronization and to explore the endogenous pacemaker. Subsequently, the fish were subjected to constant conditions of light to test whether or not locomotor rhythms are regulated by the endogenous circadian clock. The effect of increasing light length and intensity was studied on daily rhythm of locomotor activity of fish. Our results showed that the R. quelen is a strictly diurnal species, the rhythm of locomotory activity resynchronized quickly after inverting the LD cycle and persist under free course LL, suggesting a circadian origin. The light showed a significant masking effect often blocking the expression of the biological rhythm. The strictly diurnal behavior is controlled directly by the photoperiod and maintained even under very dim light (30 lux).

Effects of crude extracts of a saxitoxin-producer strain of the cyanobacterium Cylindrospermopsis raciborskii on the swimming behavior of wild and laboratory reared guppy Poecilia vivipara

The cyanobacterium Cylindrospermopsis raciborskii is an invasive species in water supply reservoirs worldwide, which can produces cylindrospermopsins and saxitoxins. In the wild, guppy (Poecilia vivipara) can be exposed to cyanotoxins, but those born and reared in laboratory are free of this contact. The aim of this paper was to comparatively measure the locomotor activity of ‘wild’ and ‘lab’ P. vivipara before and after exposure to crude extracts of two different cultures of C. raciborskii (CYRF-01), a saxitoxin-procucer strain. The movement of each fish was recorded using an image monitoring system (Videomex V®) before and after 48 h exposure to cyanobacterial extracts. Each experiment was performed during 4 h, with 1 h acclimation and 3 h recording period of the parameters Distance performed (DP), Swimming time (SwT), Stereotypic time (StT), Resting time (RT) and Average speed (AS). The quantification of saxitoxin in the solutions was performed by the enzyme-linked immunosorbent assay (ELISA). The weight or the total length did not influence the locomotor activity of fish in any of the experiments. The saxitoxin value was similar for both cultures (Culture 1: 7.3 μg L−1 and Culture 2: 8.6 μg L−1). However, in experiments with Culture 1 an increased activity in most parameters was observed, while in Culture 2, a decreased activity was observed only in ‘lab’ fish. Wild fish was less affected, showing higher resistance to both cyanobacterial crude extracts. This study showed that different cultures of the same strain of C. raciborskii and with similar contents of saxitoxin are able to change the locomotor activity of P. vivipara, contributing to the validation of the use of behavioral parameters to the evaluation of sublethal effects of toxic cyanobacteria on fish.

Influence of magnetic field on zebrafish activity and orientation in a plus maze

We describe an impact of the geomagnetic field (GMF) and its modification on zebrafish's orientation and locomotor activity in a plus maze with four arms oriented to the north, east, south and west. Zebrafish's directional preferences were bimodal in GMF: they visited two arms oriented in opposed directions (east–west) most frequently. This bimodal preference remained stable for same individuals across experiments divided by several days. When the horizontal GMF component was turned 90° clockwise, the preference accordingly shifted by 90° to arms oriented to the north and south. Other modifications of GMF (reversal of both vertical and horizontal GMF components; reversal of vertical component only; and reversal of horizontal component only) did not exert any discernible effect on the orientation of zebrafish. The 90° turn of horizontal component also resulted in a significant increase of fish's locomotor activity in comparison with the natural GMF. This increase became even more pronounced when the horizontal component was repeatedly turned by 90° and back with 1min interval between turns. Our results show that GMF and its variations should be taken into account when interpreting zebrafish's directional preferences and locomotor activity in mazes and other experimental devices.

Chronic bisphenol A exposure alters behaviors of zebrafish (Danio rerio)

The adult zebrafish (Danio rerio) were exposed to treated-effluent concentration of bisphenol A (BPA) or 17β-estradiol (E2) for 6 months to evaluate their effects on behavioral characteristics: motor behavior, aggression, group preference, novel tank test and light/dark preference. E2 exposure evidently dampened fish locomotor activity, while BPA exposure had no marked effect. Interestingly, BPA-exposed fish reduced their aggressive behavior compared with control or E2. Both BPA and E2 exposure induced a significant decrease in group preference, as well as a weaker adaptability to new environment, exhibiting lower latency to reach the top, more entries to the top, longer time spent in the top, fewer frequent freezing, and fewer erratic movements. Furthermore, the circadian rhythmicity of light/dark preference was altered by either BPA or E2 exposure. Our results suggest that chronic exposure of treated-effluent concentration BPA or E2 induced various behavioral anomalies in adult fish and enhanced ecological risk to wildlife.

The behavior of male Danio rerio Hamilton after exposure of fish embryos to a simulated geomagnetic storm

Embryos of the zebrafish, Danio rerio, were exposed to a simulated geomagnetic storm during 24 hours. Fish, developed from these embryos, left a start chamber to an aquarium more readily in comparison to those reared in a normal geomagnetic field. On the other hand, general locomotor activity in fish was not essentially different between the two groups. We hypothesize that an exposure to a geomagnetic storm during embryonic period results in enhanced tolerance to stress caused by a novel environment. A low level stress is in turn a subject to further exploration.

Magnetic fields and fish behavior

In the review, contemporary data on the influence of natural and artificial magnetic fields on fish behavior are considered. In this regard, elasmobranchs and teleosts appear to be studied most exhaustively. Elasmobranchs and some teleosts are able to perceive magnetic fields via electroreceptors. A number of teleosts can sense magnetic fields via sensory cells containing crystals of biogenic magnetite. Laboratory experiments and field observations indicate the influence of magnetic fields on fish locomotor activity and spatial distribution. The geomagnetic field can be used by fish for navigation. Besides, artificial magnetic fields and natural fluctuations of the geomagnetic field can affect fish embryos leading to alterations in their development. It is suggested that, afterwards, these alterations can have an effect on fish behavior.