Biology subjects

Dimitriadou, S.

Publications and source records attributed to Dimitriadou, S..

4 recordsLinked to original sources

bioRxiv2025

Evaluating anaesthetics for improving scientific research and welfare using larval zebrafish

Establishing anaesthesia for ensuring both animal welfare and compatibility with protocols required for different areas of scientific research is vital. Zebrafish (Danio rerio) are one of the most used animal models in research; however, little is known about the appropriateness of anaesthetic used for this species, especially for embryo-larval life stages. Using a combination of whole-brain functional imaging, quantification of cardiovascular performance, and behaviour, we explore the efficacy and tolerability of six widely used fish anaesthetics (2-phenoxyethanol, benzocaine, etomidate, MS222, isoeugenol and quinaldine sulfate) in larval zebrafish. We show that MS222 and quinaldine sulfate are the most suitable for achieving deep anaesthesia, while etomidate is better suited for studies focused on the cardiovascular system. Only quinaldine sulfate was found to be aversive. Our findings aid researchers for selecting the most suitable anaesthetic compounds and concentrations for their specific research goals, and the refinement of studies using anaesthesia in larval zebrafish.

physiology↗

bioRxiv2023

Going with the flow: evidence that cooperative individuals adjust their cooperative behaviour in response to the social environment in the Trinidadian guppy (Poecilia reticulata)

Assortative interactions can be key for the evolution and maintenance of cooperation. The propensity for cooperative behaviour to be met with equal cooperativeness can arise from partner conditional responses or fixed cooperative traits, but also a combination of both; something that has yet to be investigated outside of humans. We explored whether individuals differing in trait cooperativeness also differed in plasticity of their conditional response to partner cooperativeness. To identify when selection may favour high or low plasticity as a function of cooperativeness, we also developed an evolutionary simulation model, where individuals probability of cooperating was modelled alongside their plasticity. Our empirical results suggest that guppies (Poecilia reticulata) bred to make high cooperative investments in the context of predator inspection exhibit greater conditional response plasticity than guppies bred to make lower investments. Our agent-based model found that more cooperative individuals will show greater plasticity in their propensity to cooperate, compared to less cooperative individuals, except when there are no consequences of nobody cooperating. Combined, our findings show that more cooperative individuals might benefit from a greater capacity to adjust behaviour than less cooperative individuals - this could have implications for assortment by cooperative behaviour.

animal behavior and cognition↗

bioRxiv2021

Brain monoaminergic activity during predator inspection in the Trinidadian guppy (Poecilia reticulata)

To understand the processes underpinning social decision-making, we need to determine how internal states respond to information gathered from the social environment. Brain monoamine neurotransmitters are key in the appraisal of the social environment and can reflect the internal state underlying behavioural responses to social stimuli. Here we determined the effects of conspecific partner cooperativeness during predator inspection on brain monoamine metabolic activity in Trinidadian guppies (Poecilia reticulata). We quantified the concentration of dopamine, serotonin and their metabolites across brain sections sampled immediately after ostensibly experiencing cooperation or defection from social partners whilst inspecting a predator model. Our results indicate dopaminergic and serotonergic activity differs with the cooperativeness experienced; these different neurotransmission profiles are likely to affect the expression and regulation of downstream behaviours that ultimately contribute to the patterning of cooperative interactions among individuals in the population. List of abbreviations used

animal behavior and cognition↗

bioRxiv2021

Social partner cooperativeness influences brain oxytocin transcription in Trinidadian guppies (Poecilia reticulata)

For non-kin cooperation to be maintained, individuals need to respond adaptively to the cooperative behaviour of their social partners. Currently, however, little is known about the biological responses of individuals to experiencing cooperation. Here, we quantify the neuroregulatory response of Trinidadian guppies (Poecilia reticulata) experiencing cooperation or defection by examining the transcriptional response of the oxytocin gene (oxt; also known as isotocin), which has been implicated in cooperative decision-making. We exposed wild-caught females to social environments where partners either cooperated or defected during predator inspection, or to a control (non-predator inspection) context, and quantified the relative transcription of the oxt gene. We tested an experimental group, originating from a site where individuals are under high predation threat and have previous experience of large aquatic predators (HP), and a control group, where individuals are under low predation threat and naive to large aquatic predators (LP). In HP, but not LP, fish brain mid-section oxt relative transcription varied depending on social partner behaviour. HP fish experiencing cooperation during predator inspection had lower oxt transcription than those experiencing defection. This effect was not present in the control population or in the control context, where the behaviour of social partners did not affect oxt transcription. Our findings provide insight into the neuromodulation underpinning behavioural responses to social experiences, and ultimately to the proximate mechanisms underlying social decision-making.

animal behavior and cognition↗