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WellBeing International

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Articles 601 - 630 of 990

Full-Text Articles in Animal Sciences

Rescued Goats At A Sanctuary Display Positive Mood After Former Neglect, Elodie F. Briefer, Alan G. Mcelligott Jun 2013

Rescued Goats At A Sanctuary Display Positive Mood After Former Neglect, Elodie F. Briefer, Alan G. Mcelligott

Sentience Collection

Moods influence cognitive processes in that people in positive moods expect more positive events to occur and less negative ones (“optimistic bias”), whereas the opposite happens for people in negative moods (“pessimistic bias”). The evidence for an effect of mood on cognitive bias is also increasing in animals, suggesting that measures of optimism and pessimism could provide useful indicators of animal welfare. For obvious ethical reasons, serious poor treatments cannot be easily replicated in large mammals in order to study their long-term effects on moods. In this study, we tested the long-term effects (>2 years) of prior poor welfare …


Environmental Change Alters Personality In The Rainbow Trout, Oncorhynchus Mykiss, Ashley J. Frost, Jack S. Thomson, Charlotte Smith, Hannah C. Burton, Ben Davis, Phillip C. Watts, Lynne U. Sneddon Jun 2013

Environmental Change Alters Personality In The Rainbow Trout, Oncorhynchus Mykiss, Ashley J. Frost, Jack S. Thomson, Charlotte Smith, Hannah C. Burton, Ben Davis, Phillip C. Watts, Lynne U. Sneddon

Sentience Collection

Boldness is a personality trait that defines how individuals respond to risky situations and has clear fitness consequences. Since the adaptive value of boldness is context dependent, the benefit of a distinct personality is less clear when the environment is unpredictable. An ability to modulate behaviour can be beneficial, although as behavioural plasticity itself may be costly this depends on the levels of environmental stability. Both boldness and its plasticity are linked with physiological stress coping mechanisms, whereby animals with reduced glucocorticoid responses to stress are bolder and less flexible in behaviour. We investigated the behavioural changes made by bold …


Site Fidelity And Homing Behaviour In Intertidal Fishes, Gemma E. White, Culum Brown Jun 2013

Site Fidelity And Homing Behaviour In Intertidal Fishes, Gemma E. White, Culum Brown

Sentience Collection

The theory of ecological cognition poses that the brains and behaviour of animals are shaped by the environmental challenges they face in their everyday lives. Site fidelity and homing ability was tested for five species of intertidal rock pool fish by tagging and displacing them to new rock pools at various distances from their ‘home’ rock pools. Three of the species were rock pool specialists whilst the remaining two spend a small proportion of their life in rock pools during early ontogeny. The three specialists showed strong site fidelity with >50 % of individuals found in the same pool 42 …


Are Juvenile Domestic Pigs (Sus Scrofa Domestica) Sensitive To The Attentive States Of Humans? The Impact Of Impulsivity On Choice Behaviour, Christian Nawroth, Mirjam Ebersbach, Eberhard Von Borell Jun 2013

Are Juvenile Domestic Pigs (Sus Scrofa Domestica) Sensitive To The Attentive States Of Humans? The Impact Of Impulsivity On Choice Behaviour, Christian Nawroth, Mirjam Ebersbach, Eberhard Von Borell

Attention Collection

Previous studies have shown that apes, dogs and horses seem to be able to attribute attentive states to humans. Subjects chose successfully between two persons: one who was able to see the animal and one who was not. Using a similar paradigm, we tested a species that does not rely strongly on visual cues, the domestic pig (Sus scrofa domestica). Subjects could choose between two unfamiliar persons, with only one showing attention, in three different conditions (body, head away, body turned - head front). Subjects (n = 16) only showed a tendency towards …


Estimating Animal Population Density Using Passive Acoustics, Tiago A. Marques, Len Thomas, Stephen W. Martin, David K. Mellinger, Jessica A. Ward, Danielle Harris, Peter L. Tyack May 2013

Estimating Animal Population Density Using Passive Acoustics, Tiago A. Marques, Len Thomas, Stephen W. Martin, David K. Mellinger, Jessica A. Ward, Danielle Harris, Peter L. Tyack

Bioacoustics Collection

Reliable estimation of the size or density of wild animal populations is very important for effective wildlife management, conservation and ecology. Currently, the most widely used methods for obtaining such estimates involve either sighting animals from transect lines or some form of capture-recapture on marked or uniquely identifiable individuals. However, many species are difficult to sight, and cannot be easily marked or recaptured. Some of these species produce readily identifiable sounds, providing an opportunity to use passive acoustic data to estimate animal density. In addition, even for species for which other visually based methods are feasible, passive acoustic methods offer …


Neutering Dogs: Effects On Joint Disorders And Cancers In Golden Retrievers, Gretel Torres De La Riva, Benjamin L. Hart, Thomas B. Farver, Anita M. Oberbauer, Locksley L. Mcv Messam, Neil H. Willits, Lynette A. Hart Feb 2013

Neutering Dogs: Effects On Joint Disorders And Cancers In Golden Retrievers, Gretel Torres De La Riva, Benjamin L. Hart, Thomas B. Farver, Anita M. Oberbauer, Locksley L. Mcv Messam, Neil H. Willits, Lynette A. Hart

Endocrinology Collection

In contrast to European countries, the overwhelming majority of dogs in the U.S. are neutered (including spaying), usually done before one year of age. Given the importance of gonadal hormones in growth and development, this cultural contrast invites an analysis of the multiple organ systems that may be adversely affected by neutering. Using a single breed-specific dataset, the objective was to examine the variables of gender and age at the time of neutering versus leaving dogs gonadally intact, on all diseases occurring with sufficient frequency for statistical analyses. Given its popularity and vulnerability to various cancers and joint disorders, the …


Evolutionary Responses To Invasion: Cane Toad Sympatric Fish Show Enhanced Avoidance Learning, Georgina Caller, Culum Brown Jan 2013

Evolutionary Responses To Invasion: Cane Toad Sympatric Fish Show Enhanced Avoidance Learning, Georgina Caller, Culum Brown

Aquaculture Collection

The introduced cane toad (Bufo marinus) poses a major threat to biodiversity due to its lifelong toxicity. Several terrestrial native Australian vertebrates are adapting to the cane toad’s presence and lab trials have demonstrated that repeated exposure to B. marinus can result in learnt avoidance behaviour. Here we investigated whether aversion learning is occurring in aquatic ecosystems by comparing cane toad naı¨ve and sympatric populations of crimson spotted rainbow fish (Melanotaenia duboulayi). The first experiment indicated that fish from the sympatric population had pre-existing aversion to attacking cane toad tadpoles but also showed reduced attacks on native tadpoles. The second …


The Applicability Of The Self-Fulfillment Account Of Welfare To Nonhuman Animals, Babies, And Mentally Disabled Humans, Tatjana Visak, Jonathan Balcombe Jan 2013

The Applicability Of The Self-Fulfillment Account Of Welfare To Nonhuman Animals, Babies, And Mentally Disabled Humans, Tatjana Visak, Jonathan Balcombe

Sentience Collection

In this paper we will argue that generality is a virtue of Haybron’s account of welfare. Indeed, reflecting on the applicability of his theory to nonhuman animals will give us a better understanding of its applicability to humans. We will first focus on self-fulfillment and suggest an interpretation of Haybron’s account according to which the self-fulfillment of an individual consists in the fulfillment of the aspects of the self that are applicable to that particular individual. This makes Haybron’s account of welfare applicable to all sentient beings. Then we will focus on sub-personal nature-fulfillment and argue that the same interpretation …


Great Ape Mindreading: What’S At Stake?, Kristin Andrews Jan 2013

Great Ape Mindreading: What’S At Stake?, Kristin Andrews

Ethology Collection

Humans and other great apes are similar in so many ways. We share an extended immaturity and intense infant-caregiver relationships, group living situations, cultural transmission of technology, and many emotions and cognitive capacities. Yet the communities of nonhuman apes are also very different from human communities. Humans build lasting tools, and store them to use later. We build permanent sleeping and living structures. We cook our food. We have courts of law and prisons and ethics books. There are vast technological differences between humans and nonhuman great apes. What is it that accounts for such a difference? On one account, …


Are Apes’ Responses To Pointing Gestures Intentional?, Olivia Sultanescu, Kristin Andrews Jan 2013

Are Apes’ Responses To Pointing Gestures Intentional?, Olivia Sultanescu, Kristin Andrews

Sentience Collection

This paper examines the meaningfulness of pointing in great apes. We appeal to Hannah Ginsborg’s conception of primitive normativity, which provides an adequate criterion for establishing whether a response is meaningful, and we attempt to make room for a conception according to which there is no fundamental difference between the responses of human infants and those of other great apes to pointing gestures. This conception is an alternative to Tomasello’s view that pointing gestures and reactions to them reveal a fundamental difference between humans and other apes.


Social Learning In Juvenile Lemon Sharks, Negaprion Brevirostris, Tristan L. Guttridge, Sander Van Dijk, Eize Stamhuis, Jens Krause, Samuel Gruber, Culum Brown Jan 2013

Social Learning In Juvenile Lemon Sharks, Negaprion Brevirostris, Tristan L. Guttridge, Sander Van Dijk, Eize Stamhuis, Jens Krause, Samuel Gruber, Culum Brown

Sentience Collection

Social learning is taxonomically widespread and can provide distinct behavioural advantages, such as in finding food or avoiding predators more efficiently. Although extensively studied in bony fishes, no such empirical evidence exists for cartilaginous fishes. Our aim in this study was to experimentally investigate the social learning capabilities of juvenile lemon sharks, Negaprion brevirostris. We designed a novel food task, where sharks were required to enter a start zone and subsequently make physical contact with a target in order to receive a food reward. Naive sharks were then able to interact with and observe (a) pre-trained sharks, that is, ‘demonstrators’, …


Does True Syntax Or Simple Auditory Object Support The Role Of Skylark Song Dialect?, Elodie F. Briefer, Fanny Rybak, Thierry Aubin Jan 2013

Does True Syntax Or Simple Auditory Object Support The Role Of Skylark Song Dialect?, Elodie F. Briefer, Fanny Rybak, Thierry Aubin

Sentience Collection

Parallels between birdsong and human language are numerous and include particular temporal arrangements of acoustic units and the existence of dialects. In animal communication, modifications of the temporal ordering of existing acoustic units have rarely been clearly linked with changes in information content, particularly in a natural environment. Here, we show that the organization of birdsong units (‘syllables’) in sequences supports interindividual relationships within skylark communities. We manipulated the temporal arrangement of song dialect variants (‘shared phrases’) in the skylark, Alauda arvensis, a songbird with a very large repertoire of syllables and complex song. When tested with playback experiments performed …


Ape Autonomy? Social Norms And Moral Agency In Other Species, Kristin Andrews Jan 2013

Ape Autonomy? Social Norms And Moral Agency In Other Species, Kristin Andrews

Autonomy Collection

No abstract provided.


Do Painful Sensations And Fear Exist In Fish?, Lynne U. Sneddon Jan 2013

Do Painful Sensations And Fear Exist In Fish?, Lynne U. Sneddon

Distress Collection

The detection of pain and fear in fi sh has been subject to much debate and, since fi sh are a popular experimental model and commercially important in both angling and aquaculture, many procedures that fi sh are subjected to cause injury, fear and stress. These injuries would give rise to the sensation of pain in humans but whether fi sh have the capacity for pain is relatively under explored. Recent evidence has shown that fi sh have the same neural apparatus to detect pain that mammals and humans do, that their brain is active during a potentially painful experience, …


Associations Of Housing, Management, Milking Activity, And Standing And Lying Behavior Of Dairy Cows Milked In Automatic Systems, Justine A. Deming, Renée Bergeron, Kenneth E. Leslie, Trevor J. Devries Jan 2013

Associations Of Housing, Management, Milking Activity, And Standing And Lying Behavior Of Dairy Cows Milked In Automatic Systems, Justine A. Deming, Renée Bergeron, Kenneth E. Leslie, Trevor J. Devries

Farm Animal Husbandry Collection

The objective of this cross-sectional study was to describe the housing, feeding management, and characteristics (parity and stage of lactation) of cows on commercial automatic milking system (AMS) dairies and their associations with the standing and lying behavior patterns and milking activity (frequency and yield) of lactating dairy cows. Thirteen AMS herds were enrolled in the study, with an average herd size of 71 ± 30 (mean ± SD; range: 34 to 131) lactating cows. All of the herds used freestall barns, each set up for free cow traffic to the AMS. On-farm measurements were taken to determine stocking density …


Canine Chronic Kidney Disease In Uk Veterinary Practices: Prevalence, Risk Factors And Survival, D. G. O'Neill, J. Elliott, D. B. Church, P. D. Mcgreevy, P. C. Thomson, D. C. Brodbelt Jan 2013

Canine Chronic Kidney Disease In Uk Veterinary Practices: Prevalence, Risk Factors And Survival, D. G. O'Neill, J. Elliott, D. B. Church, P. D. Mcgreevy, P. C. Thomson, D. C. Brodbelt

Epidemiology Collection

Analyses covering 107,214 dogs attending 89 UK practices aimed to estimate the prevalence and identify risk factors associated with canine chronic kidney disease (CKD) diagnosis and survival. The apparent prevalence (AP) was estimated using a cross-sectional approach while the true prevalence (TP) was estimated using Bayesian analysis. A nested case-control study design was used to evaluate risk factors. Survival analysis was conducted using the Kaplan-Meier survival curve method and multivariable Cox proportional hazards regression modelling. CKD AP was estimated at 0.21% and TP at 0.37%. CKD risk factors included increasing age, being insured and certain breeds. The median survival time …


Benchmarking Cow Comfort On North American Freestall Dairies: Lameness, Leg Injuries, Lying Time, Facility Design, And Management For High-Producing Holstein Dairy Cows, Marina A.G. Von Keyserlingk, A. K. Barrientos, K. Ito, E. Galo, Daniel M. Weary Dec 2012

Benchmarking Cow Comfort On North American Freestall Dairies: Lameness, Leg Injuries, Lying Time, Facility Design, And Management For High-Producing Holstein Dairy Cows, Marina A.G. Von Keyserlingk, A. K. Barrientos, K. Ito, E. Galo, Daniel M. Weary

Housing and Confinement of Farm Animals Collection

In this paper, we describe a novel approach to corporate involvement in on-farm assessment, driven by the desire to provide a service for dairy producers and to create a vehicle for engagement on issues of dairy cow welfare. This program provides producers with feedback on animal-based (including gait score, leg injuries, and lying time) and facility-based (including freestall design, bedding practices, feed bunk design and management, and stocking density) measures that can be used to better address their management goals. The aim of this paper is to describe variation in the prevalence of lameness and leg injuries, lying behavior, facility …


Grey Parrot Number Acquisition: The Inference Of Cardinal Value From Ordinal Position On The Numeral List, Irene M. Pepperberg, Susan Carey Nov 2012

Grey Parrot Number Acquisition: The Inference Of Cardinal Value From Ordinal Position On The Numeral List, Irene M. Pepperberg, Susan Carey

Sentience Collection

No abstract provided.


Haemato Biochemical Alterations In Goats Infected With Coccidiosis, J. Anumol, P. V. Tresamol, K. Vinodkumar, M. R. Saseendranath Nov 2012

Haemato Biochemical Alterations In Goats Infected With Coccidiosis, J. Anumol, P. V. Tresamol, K. Vinodkumar, M. R. Saseendranath

Biochemistry Collection

Coccidiosis is an important disease which account for anaemia and associated problems like poor growth rate, suppressed resistance and high mortality in kids. While considering the various etiological factors resulting in anaemia among goats of Kerala, coccidiosis account for about 8 per cent, indicating the significance of adopting proper prevention and control measures against this disease. The present study reveals the severity and depth of anaemic changes induced by coccidia in goats. All the haematological parameters, serum biochemical parameters and serum levels of iron, copper and zinc of coccidiosis infected animals are evaluated statistically by comparing with healthy control animals.


Size And Shape Information Serve As Labels In The Alarm Calls Of Gunnison’S Prairie Dogs Cynomys Gunnisoni, C. N. Slobodchikoff, William R. Briggs, Patricia A. Dennis, Anne-Marie C. Hodge Oct 2012

Size And Shape Information Serve As Labels In The Alarm Calls Of Gunnison’S Prairie Dogs Cynomys Gunnisoni, C. N. Slobodchikoff, William R. Briggs, Patricia A. Dennis, Anne-Marie C. Hodge

Veterinary Science and Medicine Collection

Some animals have the capacity to produce different alarm calls for terrestrial and aerial predators. However, it is not clear what cognitive processes are involved in generating these calls. One possibility is the position of the predator: Anything on the ground receives a terrestrial predator call, and anything in the air receives an aerial predator call. Another possibility is that animals are able to recognize the physical features of predators and incorporate those into their calls. As a way of elucidating which of these mechanisms plays a primary role in generating the structure of different calls, we performed two field …


Association Between Stall Surface And Some Animal Welfare Measurements In Freestall Dairy Herds Using Recycled Manure Solids For Bedding, A. W. Husfeldt, M. I. Endres Oct 2012

Association Between Stall Surface And Some Animal Welfare Measurements In Freestall Dairy Herds Using Recycled Manure Solids For Bedding, A. W. Husfeldt, M. I. Endres

Housing and Confinement of Farm Animals Collection

The objective of this cross-sectional study was to investigate the association between stall surface and some animal welfare measurements in upper Midwest US dairy operations using recycled manure solids as bedding material. The study included 34 dairy operations with herd sizes ranging from 130 to 3,700 lactating cows. Forty-five percent of the herds had mattresses and 55% had deep-bedded stalls. Farms were visited once between July and October 2009. At the time of visit, at least 50% of the cows in each lactating pen were scored for locomotion, hygiene, and hock lesions. On-farm herd records were collected for the …


Mother Goats Do Not Forget Their Kids’ Calls, Elodie F. Briefer, Mónica Padilla De La Torre, Alan G. Mcelligott Sep 2012

Mother Goats Do Not Forget Their Kids’ Calls, Elodie F. Briefer, Mónica Padilla De La Torre, Alan G. Mcelligott

Sentience Collection

Parent–offspring recognition is crucial for offspring survival. At long distances, this recognition is mainly based on vocalizations. Because of maturation-related changes to the structure of vocalizations, parents have to learn successive call versions produced by their offspring throughout ontogeny in order to maintain recognition. However, because of the difficulties involved in following the same individuals over years, it is not clear how long this vocal memory persists. Here, we investigated long-term vocal recognition in goats. We tested responses of mothers to their kids’ calls 7–13 months after weaning. We then compared mothers’ responses to calls of their previous kids with …


Vocal Expression Of Emotions In Mammals: Mechanisms Of Production And Evidence, Elodie Briefer Sep 2012

Vocal Expression Of Emotions In Mammals: Mechanisms Of Production And Evidence, Elodie Briefer

Communication Skills Collection

Emotions play a crucial role in an animal’s life because they facilitate responses to external or internal events of significance for the organism. In social species, one of the main functions of emotional expression is to regulate social interactions. There has recently been a surge of interest in animal emotions in several disciplines, ranging from neuroscience to evolutionary zoology. Because measurements of subjective emotional experiences are not possible in animals, researchers use neurophysiological, behavioural and cognitive indicators. However, good indicators, particularly of positive emotions, are still lacking. Vocalizations are linked to the inner state of the caller. The emotional state …


Individual Prey Choices Of Octopuses: Are They Generalist Or Specialist?, Jennifer A. Mather, Tatiana S. Leite, Allan T. Batista Aug 2012

Individual Prey Choices Of Octopuses: Are They Generalist Or Specialist?, Jennifer A. Mather, Tatiana S. Leite, Allan T. Batista

Sentience Collection

Prey choice is often evaluated at the species or population level. Here, we analyzed the diet of octopuses of different populations with the aim to assess the importance of individual feeding habits as a factor affecting prey choice. Two methods were used, an assessment of the extent to which an individual octopus made choices of species representative of those population (PSi and IS) and 25% cutoff values for number of choices and percentage intake of individual on their prey. In one population of Octopus cf vulgaris in Bermuda individuals were generalist by IS=0.77, but most chose many prey of the …


Why (And How) Personalities In Invertebrates?, Jennifer A. Mather Aug 2012

Why (And How) Personalities In Invertebrates?, Jennifer A. Mather

Sentience Collection

No abstract provided.


Immune Responses In Lactating Holstein Cows Supplemented With Cu, Mn, And Zn As Sulfates Or Methionine Hydroxy Analogue Chelates, L. M. Nemec, J. D. Richards, C. A. Atwell, D. E. Diaz, G. I. Zanton, T. F. Gressley Aug 2012

Immune Responses In Lactating Holstein Cows Supplemented With Cu, Mn, And Zn As Sulfates Or Methionine Hydroxy Analogue Chelates, L. M. Nemec, J. D. Richards, C. A. Atwell, D. E. Diaz, G. I. Zanton, T. F. Gressley

Physiology Collection

The aim of this study was to compare effects of inorganic sulfate versus chelated forms of supplemental Cu, Mn, and Zn on milk production, plasma and milk mineral concentrations, neutrophil activity, and antibody titer response to a model vaccination. Holstein cows (n = 25) were assigned in 2 cohorts based on calving date to a 12-wk randomized complete block design study. The first cohort consisted of 17 cows that had greater days in milk (DIM; mean of 77 DIM at the start of the trial) than the second cohort of 8 cows (32 DIM at the start of the trial). …


It Pays To Cheat: Tactical Deception In A Cephalopod Social Signalling System, Culum Brown, Martin P. Garwood, Jane E. Williamson Jul 2012

It Pays To Cheat: Tactical Deception In A Cephalopod Social Signalling System, Culum Brown, Martin P. Garwood, Jane E. Williamson

Communication Skills Collection

Signals in intraspecific communication should be inherently honest; otherwise the system is prone to collapse. Theory predicts, however, that honest signalling systems are susceptible to invasion by cheats, the extent of which is largely mediated by fear of reprisal. Cuttlefish facultatively change their shape and colour, an ability that evolved to avoid predators and capture prey. Here, we show that this ability is tactically employed by male mourning cuttlefish (Sepia plangon) to mislead conspecifics during courtship in a specific social context amenable to cheating 39 per cent of the time, while it was never employed in other social contexts. Males …


Effect Of Pen Size, Group Size, And Stocking Density On Activity In Freestall-Housed Dairy Cows, E. Telezhenko, Marina A.G. Von Keyserlingk, A. Talebi, Daniel M. Weary Jun 2012

Effect Of Pen Size, Group Size, And Stocking Density On Activity In Freestall-Housed Dairy Cows, E. Telezhenko, Marina A.G. Von Keyserlingk, A. Talebi, Daniel M. Weary

Housing and Confinement of Farm Animals Collection

The purpose was to determine the effects of the physical dimensions of the pen and group size and stocking density on cow activity. Cows (randomly assigned to 4 groups of 6 animals each) were tested in pens with 24 or 12 lying places and in groups with 12 or 6 cows. All groups were tested in each of the 4 treatments with treatment order allocated using a 4 × 4 Latin square. The distance moved and the number of movements were calculated using 5-min scan sampling of video recordings over a 48-h period. Time spent lying down, number of lying …


Plasticity Of Boldness In Rainbow Trout, Oncorhynchus Mykiss: Do Hunger And Predation Influence Risk-Taking Behaviour?, Jack S. Thomson, Phillip C. Watts, Tom G. Pottinger, Lynne U. Sneddon May 2012

Plasticity Of Boldness In Rainbow Trout, Oncorhynchus Mykiss: Do Hunger And Predation Influence Risk-Taking Behaviour?, Jack S. Thomson, Phillip C. Watts, Tom G. Pottinger, Lynne U. Sneddon

Ethology Collection

Boldness, a measure of an individual's propensity for taking risks, is an important determinant of fitness but is not necessarily a fixed trait. Dependent upon an individual's state, and given certain contexts or challenges, individuals may be able to alter their inclination to be bold or shy in response. Furthermore, the degree to which individuals can modulate their behaviour has been linked with physiological responses to stress. Here we attempted to determine whether bold and shy rainbow trout, Oncorhynchus mykiss, can exhibit behavioural plasticity in response to changes in state (nutritional availability) and context (predation threat). Individual trout were initially …


Blood Cortisol Concentrations Predict Boldness In Juvenile Mulloway (Argyosomus Japonicus), Vincent Raoult, Culum Brown, Amina Zuberi, Jane E. Williamson May 2012

Blood Cortisol Concentrations Predict Boldness In Juvenile Mulloway (Argyosomus Japonicus), Vincent Raoult, Culum Brown, Amina Zuberi, Jane E. Williamson

Sentience Collection

There is a growing interest in animal personality because individual variation is the substrate of the evolutionary process. Despite revelations that personality traits affect key fitness variables, little is known about the proximate mechanisms generating consistent behavioural differences between individuals. Boldness, the propensity to take risks, is one of the most widely studied aspects of personality in fishes. We assessed the position of juvenile Argyosomus japonicus on the ‘‘boldness–shyness’’ continuum by repeatedly recording the time taken to exit a refuge and explore a novel environment. Stress-related hormone concentrations after exposure to a mild stressor were analysed 1 month before behavioural …