8 research outputs found

    Are Large Dogs Smarter Than Small Dogs? Investigating Within Species Differences in Large and Small Dogs: Spatial Memory

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    The study of canine cognition can be useful in understanding the ontology and selective pressures that affect the development of cognitive abilities. Dogs have undergone intensive artificial selection yielding distinctive breeds which differ both phenotypically and behaviorally. Breed based cognitive differences have not been found but some studies suggest there may be differences in broader categories such as working disposition and sex. The influence of size on canine cognition has not been thoroughly addressed despite the fact that large dogs are often perceived to be ‘smarter’ than small dogs. This preconception has only recently been addressed and supported in one study comparing large and small dogs in a social cognition task where large dogs outperformed small dogs in a pointing choice task. Here I assessed the cognitive differences of large and small dogs using a series of spatial cognition tasks. As predicted there were no differences between large and small dogs, although small differences were found between males and females when spay/neuter status was accounted for. Therefore, it is unlikely that disparities found in social cognition tasks are due to genetic or physiological differences related to size. Instead it is probable that differences in cognitive performance are based on other factors such as prior training experience or past experience with humans in general

    Signature Whistle Production during a Bottlenose Dolphin Group Integration

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    Bottlenose dolphins are an important species of interest because they possess a variety of abilities that are relatively rare in the animal kingdom, one being complex acoustic communication. Signature whistles - distinctive calls that are unique for each individual – are one of the most studied call types, but we know little about how these calls are used in various contexts, such as during an introduction. Looking at the socio-behavioral context in which signature whistles are used is likely the best way of learning how these whistles are used in a particular context (Caldwell, Caldwell, & Tyack, 1990). For this project, the behavior and vocalizations of dolphins that were being introduced for the first time were analyzed to assess how signature whistle production and behavior changed after introduction. The new individual, a juvenile male, was kept physically, but not visually and acoustically, separated during the introduction. Signature whistle production for the new dolphin declined steeply on the day of introduction, increased the following week, and almost fully recovered over a month later. Overall, he produced approximately three times more signature whistles than the other dolphins. The resident female showed interest in the new individual following the initial introduction, and her signature whistle production increased after the introduction. The resident adult male showed little interest in the newcomer and his signature whistle production increased slightly. Following introduction, there were only slight changes in the behavior of resident group members, which included increased circle swimming and object play. Circle swimming also increased significantly for the new individual. There were no differences in social behavior and no agonistic behaviors were observed. The new dolphin’s decrease in signature whistling on the day of introduction was unexpected but may be due to individual differences in response to stress. In some ways, these findings are inconsistent with the few reports of typical bottlenose dolphin behavior during an introduction. Information from additional introductions will be needed to determine if the patterns of signature whistle usage and behavior seen here are typical of the range of behaviors exhibited in this context

    Is Enrichment Always Enriching and How Would You Know? Unintended Consequences and the Importance of Formal Assessment of Enrichment Programs in Bottlenose Dolphins (Tursiops truncatus)

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    Bottlenose dolphins (Tursiops truncatus) are viewed as a highly intelligent species capable of complex behaviors. This requires marine parks to maintain dynamic environmental enrichment programs in order to ensure dolphins’ optimal psychological and physiological well-being while in human care. In this study, two experiments were conducted to determine the effects of different forms of enrichment on the behavior of four bottlenose dolphins. In Experiment 1, multiple forms of novel enrichment resulted in a shift away from individual swim patterns – a change that is associated with increased behavioral diversity and so often considered an improvement in animal welfare – but also resulted in avoidance behavior and initially resulted in a decrease in affiliative behavior. In Experiment 2, introducing choice of enrichments resulted in unintended social consequences, such as agonistic behaviors. These two experiments together demonstrated that interpreting the results of enrichment programs may not be as straightforward as often presumed. The results suggest that unique forms of enrichment and variable schedules might be particularly effective but also that consistent evaluation continues to be necessary to minimize unintended behavioral consequences

    Convalescent plasma in patients admitted to hospital with COVID-19 (RECOVERY): a randomised controlled, open-label, platform trial

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    SummaryBackground Azithromycin has been proposed as a treatment for COVID-19 on the basis of its immunomodulatoryactions. We aimed to evaluate the safety and efficacy of azithromycin in patients admitted to hospital with COVID-19.Methods In this randomised, controlled, open-label, adaptive platform trial (Randomised Evaluation of COVID-19Therapy [RECOVERY]), several possible treatments were compared with usual care in patients admitted to hospitalwith COVID-19 in the UK. The trial is underway at 176 hospitals in the UK. Eligible and consenting patients wererandomly allocated to either usual standard of care alone or usual standard of care plus azithromycin 500 mg once perday by mouth or intravenously for 10 days or until discharge (or allocation to one of the other RECOVERY treatmentgroups). Patients were assigned via web-based simple (unstratified) randomisation with allocation concealment andwere twice as likely to be randomly assigned to usual care than to any of the active treatment groups. Participants andlocal study staff were not masked to the allocated treatment, but all others involved in the trial were masked to theoutcome data during the trial. The primary outcome was 28-day all-cause mortality, assessed in the intention-to-treatpopulation. The trial is registered with ISRCTN, 50189673, and ClinicalTrials.gov, NCT04381936.Findings Between April 7 and Nov 27, 2020, of 16 442 patients enrolled in the RECOVERY trial, 9433 (57%) wereeligible and 7763 were included in the assessment of azithromycin. The mean age of these study participants was65·3 years (SD 15·7) and approximately a third were women (2944 [38%] of 7763). 2582 patients were randomlyallocated to receive azithromycin and 5181 patients were randomly allocated to usual care alone. Overall,561 (22%) patients allocated to azithromycin and 1162 (22%) patients allocated to usual care died within 28 days(rate ratio 0·97, 95% CI 0·87–1·07; p=0·50). No significant difference was seen in duration of hospital stay (median10 days [IQR 5 to >28] vs 11 days [5 to >28]) or the proportion of patients discharged from hospital alive within 28 days(rate ratio 1·04, 95% CI 0·98–1·10; p=0·19). Among those not on invasive mechanical ventilation at baseline, nosignificant difference was seen in the proportion meeting the composite endpoint of invasive mechanical ventilationor death (risk ratio 0·95, 95% CI 0·87–1·03; p=0·24).Interpretation In patients admitted to hospital with COVID-19, azithromycin did not improve survival or otherprespecified clinical outcomes. Azithromycin use in patients admitted to hospital with COVID-19 should be restrictedto patients in whom there is a clear antimicrobial indication

    Does Size Really Matter? Investigating Cognitive Differences In Spatial Memory Ability Based On Size In Domestic Dogs

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    The study of canine cognition can be useful in understanding the selective pressures affecting cognitive abilities. Dogs have undergone intensive artificial selection yielding distinctive breeds, which differ both phenotypically and behaviorally and no other species has a wider range in brain size. As brain size has long been hypothesized to relate to cognitive capacity, this species offers a useful model to further explore this relationship. The influence of physical size on canine cognition has not been thoroughly addressed, despite the fact that large dogs are often perceived to be ‘smarter’ than small dogs. To date, this preconception has only recently been addressed and supported in one study comparing large and small dogs in a social cognition task, where large dogs outperformed small dogs in a pointing choice task. We assessed large and small dogs using a series of spatial cognition tasks and detected no differences between the two groups. Further research is needed to clarify why our results failed to compliment previous findings. It is possible that differences found in social cognition tasks may not be due to differences in size, rather they may be based on other factors such as methodology, prior training experience, or past experience with humans in general
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