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1.
Environ Sci Pollut Res Int ; 27(31): 38559-38567, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32623676

RESUMO

Due to human activities, there is an increasing presence of agrochemicals residues in water bodies, which could be attributed to an increased use of these chemicals, incorrect disposal of packaging materials, and crop leaching. The effects of these residues on prey-predator relationship of aquatic animals are poorly known. Here, we show that fish acutely exposed to glyphosate, 2,4-D, and methylbenzoate-based agrichemicals have their anti-predatory responses impaired. We exposed zebrafish to sub-lethal concentrations of agrichemicals and evaluated their behavioral reaction against a simulated bird predatory strike. We observed that agrichemical-exposed fish spent more time in a risky area, suggesting that the pesticides interfered with their ability of risk perception. Our results highlight the impairment and environmental consequences of agrochemical residues, which can affect aquatic life and crucial elements for life (food web) such as the prey-predator relationship.


Assuntos
Poluentes Químicos da Água/toxicidade , Peixe-Zebra , Agroquímicos , Animais , Cadeia Alimentar , Humanos , Comportamento Predatório
2.
Sci Rep ; 10(1): 12050, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32694657

RESUMO

The prior residence effect consists of a higher probability of territory owners to win a fight against intruders, as observed in several territorial species across animal kingdom. However, in investigations on territorial behavior, intruder traits have been assumed as fixed. Thus, we used a territorial species as experimental model to evaluate the effect of intruder traits on aggressive behavior of territory owners. During fights staged between territory owners and intruders, intruder traits, linked with visual signals of social status (dominant-subordinate position), modulate fighting behavior of territory owners, but prior residence effect still occurred. Intruder traits must be addressed more effectively for improving the theoretical understanding of territoriality.

3.
Physiol Behav ; 222: 112944, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32407833

RESUMO

Zebrafish has become an animal model in research and articles have established ideal conditions for their maintenance. However, little is known regarding the influence of gender and other cues on zebrafish behavior. Thus, here we analyzed the exploratory and social behavior of different sexes (male and female, mixed or segregated) under different housing conditions with various types of stimuli (visual or/and chemical cues and structural environmental enrichment). Segregated females and males were more active than mixed individuals and females were more anxious. Fish that visualized and smelled the opposite sex presented higher activity and were less anxious than individuals that only smelled or visualized the opposite sex. Fish segregated by sex while being allowed to visualize and smell the opposite sex with the presence of structural environmental enrichment exhibited lower activity and anxiety-like behavior than fish without structural environmental enrichment. Thus, we emphasized that these variables should be taken into account in housing conditions and should be detailed for better replicability and reproducibility of experiments performed with zebrafish.

4.
Physiol Behav ; 206: 259-263, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-30817973

RESUMO

Several fish species trigger defensive behavioral responses when exposed to chemical cues that indicate predation risk. In these situations, physiological adjustments are also necessary to prepare the organism for a defensive response and increase survival odds. Chemical cues may be derived from predator odor or injured conspecifics. However, little is known about the effects of both cues combined. Therefore, our study evaluated the combined effects of predator odor (PO) and conspecific alarm substance (CAS) on the anti-predatory responses of the pearl cichlid (Geophagus brasiliensis). We set 4 experimental conditions 1) PO + CAS; 2) PO + Distilled Water (DW); 3) DW + CAS; and 4) DW + DW (negative control). Fish exposed to DW + CAS had values of ventilation rate and feeding latency significantly higher than when exposed to the other conditions, which yielded similar responses for both variables. Our data show that the combination of PO + CAS interfered with pearl cichlid behavior and physiology since it abolished CAS defensive responses. These results show that CAS plays an important role on the defensive responses of pearl cichlids, while PO does not, given that fish did not respond to PO by itself. Our findings point to different cue-specific strategies in pearl cichlids when dealing with different chemical cues that indicate predation risk.


Assuntos
Comunicação Animal , Comportamento Animal/fisiologia , Ciclídeos/fisiologia , Animais , Sinais (Psicologia) , Odorantes , Comportamento Predatório/fisiologia
5.
PeerJ ; 5: e3739, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28890851

RESUMO

Chemical communication relating to predation risk is a trait common among fish species. Prey fish under threat of predation can signal risk to conspecific fish, which then exhibit defensive responses. Fish also assess predation risk by visual cues and change their behavior accordingly. Here, we explored whether these behavioral changes act as visual alarm signals to conspecific fish that are not initially under risk. We show that shoals of zebrafish (Danio rerio) visually exposed to a predator display antipredator behaviors. In addition, these defensive maneuvers trigger antipredator reactions in conspecifics and, concomitantly, stimulate the hypothalamus-pituitary-interrenal axis, leading to cortisol increase. Thus, we conclude that zebrafish defensive behaviors act as visual alarm cues that induce antipredator and stress response in conspecific fish.

6.
Physiol Behav ; 179: 319-323, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28673506

RESUMO

The chemical detection of predation risk is direct when based on predator odors, or indirect when an injured conspecific or heterospecific signal it. Physiological adjustments may be necessary in parallel to defensive reactions to cope with an imminent risk. Here, we tested the effects of predator odors and conspecific chemical alarm cues in ventilation response (VR) of frillfin goby, Bathygobius soporator, because this response increases oxygen uptake for supporting behavioral tasks. No VR change was detected in response to odors of predators (catfish) that fed on conspecific, heterospecific fish (tilapia), or were deprived of food and to non-predator (tilapia) that fed chow (non-specific odor control) and odor eluent. The goby's VR, however, increased in response to conspecific alarm cues, but not to heterospecific cues or eluent. Clearly, the VR response in fish depends on the nature of the chemical cue. It is in line with 'threat-sensitive hypothesis' as a chemical cue from an injured prey might mean a foraging predator, whilst the mere presence of a predator odor might not. In addition, because VR can increase, decrease or remains unchanged in response to predation risk in other fish species (including other gobies), we reinforces the species-specific chracteristic of VR responses in fish, regarding the results obtained here for frillfin gobies.


Assuntos
Percepção Olfatória , Perciformes/fisiologia , Respiração , Comportamento Social , Estresse Psicológico/fisiopatologia , Adaptação Psicológica , Análise de Variância , Animais , Peixes-Gato , Sinais (Psicologia) , Odorantes , Comportamento Predatório , Distribuição Aleatória
7.
Fish Physiol Biochem ; 43(1): 193-201, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27554252

RESUMO

In this study, I show that mianserin, a chemical with serotonin and adrenoceptor antagonist activities, increases fish vulnerability to a potential predator threat, when prey fish must deal with this threat based on conspecific chemical alarm cues. For that, I evaluated whether mianserin, diluted in the water, influences the behavioral responses of Nile tilapia (Oreochromis niloticus) to conspecific skin extract (chemical alarm cues). I found that, while mianserin did not abolished antipredator responses, this drug mitigates some components of this defensive reaction. Thus, a potential decrease in serotonin and adrenergic activities reduces the ability of dealing with predators when perceiving conspecific chemical alarm cues.


Assuntos
Antagonistas Adrenérgicos alfa/farmacologia , Comportamento Animal/efeitos dos fármacos , Mianserina/farmacologia , Feromônios/farmacologia , Antagonistas da Serotonina/farmacologia , Pele/química , Animais , Ciclídeos/fisiologia , Sinais (Psicologia) , Feminino , Masculino , Natação
8.
Artigo em Inglês | MEDLINE | ID: mdl-27778069

RESUMO

In fish, defensive reactions are induced by different chemical cues that emanate from sense-related stresses [physical, chemical, and visual (visual contact with predator)] or food stresses (acute fasting and chronic food restriction). Using a shuttle box with a two-chamber unmixed laminar flow that allowed fish to remain or flee from a chemical cue, we showed that the avoidance response depended on the type of the chemical cue. We show that zebrafish (Danio rerio) retreated from water conditioned with chemical cues released by chemically or physically stressed fish and acutely fasted fish, but not from water with cues from fish experiencing visual contact with predatory fish or fish suffering from chronic food restriction. Our data reinforced the hypothesis that fish use a combination of information and the context of the situation to determine their evasion strategy.


Assuntos
Água/química , Peixe-Zebra , Animais , Aprendizagem da Esquiva/fisiologia , Comportamento de Escolha , Sinais (Psicologia) , Privação de Alimentos/fisiologia , Comportamento Predatório/fisiologia , Estresse Fisiológico/fisiologia , Natação , Percepção Visual , Peixe-Zebra/fisiologia
9.
Physiol Behav ; 165: 22-7, 2016 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-27371502

RESUMO

Several fish species exhibit antipredator responses when exposed to chemicals which indicate risk of predation. One such substance is the scent of a predator (a kairomone) that may induce defensive responses in a potential prey. In the present study, we show that chemical cues (odour) from predator fish induce antipredator and stress responses in Nile tilapia. When exposed to predator odour, Nile tilapia decreased activity and increased ventilation rate (VR), but no increase in plasma levels of cortisol and glucose was found. Although the hypothalamic-pituitary-interrenal axis (HPI axis) was not activated, an increase in ventilation is a fast response which can provide the fish enough oxygen for a 'fight or flight' event when facing a predator. Thus, this respiratory response suggests an anticipated adjustment in order to prepare the body for a defensive response, such as escaping, irrespective of HPI axis activation.


Assuntos
Ciclídeos/fisiologia , Odorantes , Estresse Psicológico/fisiopatologia , Animais , Glicemia/metabolismo , Carpas , Peixes-Gato , Hidrocortisona/sangue , Atividade Motora , Consumo de Oxigênio , Comportamento Predatório
10.
Arch Environ Contam Toxicol ; 71(3): 415-22, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27423874

RESUMO

In agriculture intensive areas, fishponds and natural water bodies located in close proximity to these fields receive water with variable amounts of agrichemicals. Consequently, toxic compounds reach nontarget organisms. For instance, aquatic organisms can be exposed to tebuconazole-based fungicides (TBF), glyphosate-based herbicides (GBH), and atrazine-based herbicides (ABH) that are potentially dangerous, which motivates the following question: Are these agrichemicals attractant or aversive to fish? To answer this question, adult zebrafish were tested in a chamber that allows fish to escape from or seek a lane of contaminated water. This attraction and aversion paradigm was evaluated with zebrafish in the presence of an acute contamination with these compounds. We showed that only GBH was aversive to fish, whereas ABH and TBF caused neither attraction nor aversion for zebrafish. Thus, these chemicals do not impose an extra toxic risk by being an attractant for fish, although TBF and ABH can be more deleterious, because they induce no aversive response. Because the uptake and bioaccumulation of chemicals in fish seems to be time- and dose-dependent, a fish that remains longer in the presence of these substances tends to absorb higher concentrations than one that escapes from contaminated sites.


Assuntos
Agroquímicos/toxicidade , Peixes/fisiologia , Poluentes Químicos da Água/toxicidade , Animais , Aprendizagem da Esquiva , Comportamento Animal , Testes de Toxicidade , Peixe-Zebra
11.
PLoS One ; 10(12): e0145121, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26682546

RESUMO

Cheliped loss through autotomy is a common reflexive response in decapod crustaceans. Cheliped loss has direct and indirect effects on feeding behavior which can affect population dynamics and the role of species in the community. In this study, we assessed the impact of autotomy (0, 1, or 2 cheliped loss) on feeding behavior in the crab Pachygrapsus transversus, an omnivorous and abundant species that inhabits subtropical intertidal rocky shores along the South Atlantic Ocean. Autotomy altered crab feeding patterns and foraging behavior; however, the time spent foraging on animal prey or algae was not affected. These results indicate a plasticity of feeding behavior in P. transversus, allowing them to maintain feeding when injured.


Assuntos
Braquiúros/fisiologia , Extremidades/fisiologia , Animais , Comportamento Alimentar/fisiologia , Modelos Biológicos
12.
Physiol Behav ; 149: 8-13, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25992478

RESUMO

In predator­prey encounters between fish in which there is physical trauma to the epidermis of the prey, some species release chemical alarm cues into the water. Fish of the same species may perceive these cues and display antipredator behavior. Physiological adjustments may also be needed to deal with this adverse situation. To date, little attention has been devoted to the physiological adjustments that may co-occur with defensive responses. We have characterized the alarm cue-induced antipredator behaviors and stress responses in Nile tilapia, Oreochromis niloticus. Specifically, chemical alarm cues decreased feeding activity and induced dashing reactions while also inducing the primary stress responses, increased ventilation rate and cortisol level. Glucose levels remained unaltered, leading to the conclusion that secondary stress responses were not induced in this study. Nile tilapia stress responses to chemical alarm cues differed from those reported for other fish species, and may depend on the nature of the stimulus or on the species studied. Future studies should ideally aim to identify patterns in stress response to chemical alarm cues in fishes and resolve this question.


Assuntos
Comunicação Animal , Sinais (Psicologia) , Comportamento Predatório/fisiologia , Estresse Psicológico/metabolismo , Tilápia/fisiologia , Análise de Variância , Animais , Ensaio de Imunoadsorção Enzimática , Reação de Fuga/fisiologia , Hidrocortisona/sangue , Pele/química , Olfato/fisiologia
13.
Neotrop. ichthyol ; 13(1): 237-244, Jan-Mar/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-744510

RESUMO

Bile acids are potent olfactory and gustatory stimulants for fish. Electro-olfactogram recording was used to test whether the olfactory epithelium of pintado catfish Pseudoplatystoma corruscans is specifically sensitive to bile acids, some of which have been hypothesized to function as pheromones. Five out of 30 bile acids that had been pre-screened for olfactory activity in fish were selected. Cross-adaptation experiments demonstrated that sensitivity to bile acids is attributable to at least 3 independent classes of olfactory receptor sites. The taurocholic acid (TCA) and taurochenodeoxycholic acid (TCD) were the most potent compounds. By using avoidance/preference tests, we found that P. corruscans prefers water containing TCA. Bile acids are discriminated by olfactory epithelium of pintado, supporting that these compounds could function as pheromones.


Os ácidos biliares são potentes estimulantes olfatórios e gustatórios em peixes. Registros em eletro-olfactograma foram usados para testar se o epitélio olfatório de Pseudoplatystoma corruscans, pintado, é sensível aos ácidos biliares, alguns dos quais têm sido propostos como feromônios. Foram selecionados cinco de uma lista de trinta ácidos biliares previamente testados em atividade olfatória em peixes. Testes de adaptação cruzada demonstraram que a sensibilidade aos ácidos biliares se dá por 3 classes independentes de sites de receptores olfatórios. O ácido taurocólico (TCA) e o ácido tauroquenodesoxicólico (TCD) foram os compostos mais potentes. Em testes de evasão/preferência, P. corruscans prefere água contendo o ácido TCA. Os ácidos biliares são discriminadas por epitélio olfatório de pintado, evidenciando que estes compostos podem funcionar como feromônios.


Assuntos
Animais , Ácidos e Sais Biliares/efeitos adversos , Comportamento Sexual Animal , Feromônios/efeitos adversos , Adaptação Biológica
14.
Horm Behav ; 65(4): 394-400, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24657662

RESUMO

We evaluated the effect of increased plasma cortisol levels on fish antipredator behavior induced by conspecific chemical alarm cues. The experimental model for the study was the Frillfin goby Bathygobius soporator. We first confirmed that the alarm substance induces typical defensive antipredator responses in Frillfin gobies and described their alarm substance cells (epidermal 'club' cells). Second, we confirmed that intraperitoneal cortisol implants increase plasma cortisol levels in this species. We then demonstrated that exogenous cortisol administration and subsequent exposure to an alarm substance decreased swimming activity to a greater extent than the activity prompted by either stimulus alone. In addition, cortisol did not abolish the sheltering response to the alarm chemical cue even though it decreased activity. As predators use prey movements to guide their first contact with the prey, a factor that decreases swimming activity clearly increases the probability of survival. Consequently, this observation indicates that cortisol helps improve the antipredator response in fish.


Assuntos
Comportamento Animal/fisiologia , Hidrocortisona/sangue , Perciformes/fisiologia , Animais , Comportamento Animal/efeitos dos fármacos , Células Epidérmicas , Hidrocortisona/administração & dosagem , Hidrocortisona/farmacologia , Feromônios/farmacologia , Estimulação Química
15.
Horm Behav ; 65(4): 340-4, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24613177

RESUMO

Living animals exploit information released from dead animals to conduct adaptive biological responses. For instance, a recently published study has shown that avoidance behavior is triggered by death-associated odors in zebrafish. Stress can clearly act as an adaptive response that allows an organism to deal with an imminent threat. However, it has not been demonstrated whether these chemical cues are stressful for fish. Here, we confirmed that dead zebrafish scents induce defensive behavior in live conspecifics. Additionally, we show for the first time in fish that these scents increase cortisol in conspecifics. To reach this conclusion, firstly, we exposed zebrafish to multi-sensorial cues (e.g., visual, tactile, chemical cues) from dead conspecifics that displayed defensive behaviors and increased cortisol. Also, when we limited zebrafish to chemical cues from dead conspecifics, similar responses arose. These responses coincide with the decaying destruction of epidermal cells, indicating that defensive and stress responses could take place as an effect of substances emanating from decaying flesh, as well as alarm substance released due to rupture of epidermal cells. Taken together, these results illustrate that living zebrafish utilize cues from dead conspecific to avoid or to cope with danger and ensure survival.


Assuntos
Comportamento Animal/fisiologia , Morte , Sensação/fisiologia , Estresse Psicológico/etiologia , Peixe-Zebra/fisiologia , Animais , Feminino , Hidrocortisona/metabolismo , Masculino , Odorantes , Olfato/fisiologia , Estresse Psicológico/induzido quimicamente , Estresse Psicológico/metabolismo
16.
Behav Processes ; 105: 15-8, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24525358

RESUMO

Although sex of mature fish is known to influence aggression, this issue has so far been neglected in juveniles. Here, we tested this sex effect and showed that it does not significantly affect intraspecific aggression in juveniles of the cichlid Nile tilapia. To reach this conclusion, we measured the latency period before onset of confrontation, the frequency and types of aggressive interactions, the duration of a dispute, and the probability of becoming dominant. This was done on pairs of Nile tilapia that varied by sex: females×females, males×males, and females×males. In a double blind approach, after pairing, the sex of each individual was histologically verified and contrasted with behavioral data.


Assuntos
Agressão/fisiologia , Comportamento Animal/fisiologia , Ciclídeos/fisiologia , Predomínio Social , Animais , Feminino , Masculino , Fatores Sexuais
17.
PLoS One ; 8(10): e75780, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24116073

RESUMO

The effects of ethanol exposure on Danio rerio have been studied from the perspectives of developmental biology and behavior. However, little is known about the effects of ethanol on the prey-predator relationship and chemical communication of predation risk. Here, we showed that visual contact with a predator triggers stress axis activation in zebrafish. We also observed a typical stress response in zebrafish receiving water from these conspecifics, indicating that these fish chemically communicate predation risk. Our work is the first to demonstrate how alcohol effects this prey-predator interaction. We showed for the first time that alcohol exposure completely blocks stress axis activation in both fish seeing the predator and in fish that come in indirect contact with a predator by receiving water from these conspecifics. Together with other research results and with the translational relevance of this fish species, our data points to zebrafish as a promising animal model to study human alcoholism.


Assuntos
Comunicação Animal , Comportamento Animal/efeitos dos fármacos , Etanol/farmacologia , Comportamento Predatório/efeitos dos fármacos , Animais , Comportamento Animal/fisiologia , Hidrocortisona/metabolismo , Comportamento Predatório/fisiologia , Estresse Fisiológico/fisiologia , Peixe-Zebra/metabolismo
18.
PLoS One ; 8(3): e59134, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23516606

RESUMO

Nile tilapia fish were individually reared under similar light levels for 8 weeks under five colored light spectra (maximum wavelength absorbance): white (full light spectrum), blue (∼452 nm), green (∼516 nm), yellow (∼520 nm) or red (∼628 nm). The effects of light on feeding, latency to begin feeding, growth and feed conversion were measured during the last 4 weeks of the study (i.e., after acclimation). We found that red light stimulates feeding, as in humans, most likely by affecting central control centers, but the extra feeding is not converted into growth.


Assuntos
Comportamento Alimentar/efeitos dos fármacos , Peixes/crescimento & desenvolvimento , Peixes/fisiologia , Luz , Animais
19.
PLoS One ; 8(1): e54642, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23349945

RESUMO

In this study, we show that the fish Nile tilapia displays an antipredator response to chemical cues present in the blood of conspecifics. This is the first report of alarm response induced by blood-borne chemical cues in fish. There is a body of evidence showing that chemical cues from epidermal 'club' cells elicit an alarm reaction in fish. However, the chemical cues of these 'club' cells are restricted to certain species of fish. Thus, as a parsimonious explanation, we assume that an alarm response to blood cues is a generalized response among animals because it occurs in mammals, birds and protostomian animals. Moreover, our results suggest that researchers must use caution when studying chemically induced alarm reactions because it is difficult to separate club cell cues from traces of blood.


Assuntos
Ciclídeos/fisiologia , Sinais (Psicologia) , Reação de Fuga/fisiologia , Feromônios/fisiologia , Comunicação Animal , Animais , Aprendizagem da Esquiva/fisiologia , Ciclídeos/sangue , Feromônios/química
20.
PLoS One ; 7(1): e29746, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22272244

RESUMO

Approximately 50 years ago, Nile tilapia were accidentally introduced to Brazil, and the decline of pearl cichlid populations, which has been intensified by habitat degradation, in some locations has been associated with the presence of Nile tilapia. There is, however, little strong empirical evidence for the negative interaction of non-native fish populations with native fish populations; such evidence would indicate a potential behavioural mechanism that could cause the population of the native fish to decline. In this study, we show that in fights staged between pairs of Nile tilapia and pearl cichlids of differing body size, the Nile tilapia were more aggressive than the pearl cichlid. Because this effect prevailed over body-size effects, the pearl cichlids were at a disadvantage. The niche overlap between the Nile tilapia and the pearl cichlid in nature, and the competitive advantage shown by the Nile tilapia in this study potentially represent one of several possible results of the negative interactions imposed by an invasive species. These negative effects may reduce population viability of the native species and cause competitive exclusion.


Assuntos
Agressão/fisiologia , Tamanho Corporal/fisiologia , Ecossistema , Peixes/crescimento & desenvolvimento , Animais , Brasil , Ciclídeos/crescimento & desenvolvimento , Peixes/classificação , Espécies Introduzidas , Dinâmica Populacional , Especificidade da Espécie , Territorialidade
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