1,064 research outputs found
Survey of breeders’ management of horses in Europe, North America and Australia: comparison of factors associated with the development of abnormal behaviour
No full textAn online survey of domestic horse breeders in the USA, UK, Australia, Canada and mainland Europe was carried out in order to examine management risk factors associated with the development of abnormal behaviour patterns. One hundred and forty breeders responded, and epidemiological results suggested that the overall number of horses showing abnormal behaviours may be declining (5.2% of the sample). However, as found in previous studies, extensive, as opposed to intensive management practices reduce the risk of foals developing abnormal behaviours. In addition, offering foals low-energy forage in higher quantities reduces the risk of abnormal behaviour (P < 0.001). Results are discussed in relation to previous surveys, and suggestions are made for breeders and owners to help reduce the risks of young horses developing abnormal behaviours associated with weaning practices
Impaired instrumental choice in crib-biting horses (Equus caballus)
No full textHorses displaying an oral stereotypy were tested on an instrumental choice paradigm to examine differences in learning from non-stereotypic counterparts. The paradigm was specifically applied in order to examine learning that requires maintenance of response-outcome judgements. The stereotypic horses were found not to choose a more immediate reinforcer over three learning sessions. This suggests an initial behavioural correlate for dorsomedial striatum dysregulation in the stereotypy phenotype
Silcrete plant fossils from Lightning Ridge, New South Wales: new evidence for climate change and monsoon elements in the Australian Cenozoic
No full textDiverse Cenozoic (possibly latest Oligocene to mid–late Miocene) macrofossils from the Lightning Ridge opal fields are illustrated and discussed. Specimens identified to, or closely comparable with, extant taxa include ferns (Lygodium, Gleichenia and others), conifers now extinct in Australia (Dacrydium, Retrophyllum and Papuacedrus), Lauraceae (Cryptocarya/Cinnamomum), sclerophyllous Proteaceae (Banksia, Lomatia and Grevillea), Cunoniaceae/Elaeocarpaceae and Eucalyptus (and/or other Myrtaceae). Overall, at least four fern, three conifer and 30 angiosperm taxa are recognised. The climate supported many species with close relatives in wet Australasian habitats, including rainforests. However, a drier or more seasonal (?monsoonal) aspect is especially indicated by the presence of lobed leaves that resemble extant species of Brachychiton (Malvaceae), Erythrina (Fabaceae) and tribe Cercideae (Fabaceae). A degree of water stress is also suggested by the prevalence of narrow, toothed and/or deeply lobed angiosperm leaves.Raymond J. Carpenter, Matthew P. Goodwin, Robert S. Hill and Karola Kanol
Smarter choices ?changing the way we travel. Case study reports
No full textThis report accompanies the following volume:Cairns S, Sloman L, Newson C, Anable J, Kirkbride A and Goodwin P (2004)Smarter Choices ? Changing the Way We Travel. Report published by theDepartment for Transport, London, available via the ?Sustainable Travel? section ofwww.dft.gov.uk, and from http://eprints.ucl.ac.uk/archive/00001224/
Differential place and response learning in horses displaying an oral stereotypy
No full textSignificant similarities exist between the neural and behavioural features of environmentally and drug-induced stereotypy. For example, exposure to dopamine agonists, such as amphetamine, induces stereotypy and causes alterations in midbrain neurophysiology similar to those observed following chronic stress. An additional behavioural feature of these neural
29 changes in the drug-induced phenotype is an enhanced rate of switching from response-outcome (R-O) to stimulus-response (S-R) learning. The aim of the current experiment was to examine O and S-R learning in horses displaying environmentally-induced oral stereotypies. This was achieved by employing variations of a place-response paradigm. In Experiment 1, we found that crib-biting horses displayed ‘response’ learning after 20-learning trials, whereas non-crib-biting controls tended to display ‘place’ learning throughout the experiment. In Experiment 2, we used a modified version of the place-response paradigm, where the subjects were introduced to the maze from different start points and forced always to turn the same way. We found that the crib biters acquired the task at a faster rate suggesting again that this group were displaying ‘response’ learning. Finally, in Experiment 3, we carried out an arena test to ensure that crib biters were capable of ‘place’ learning. These results are the first to show that horses displaying an oral stereotypy, a behavioural phenotype previously associated with stress-induced perturbations of the basal ganglia, preferentially use ‘response’ learning. The findings are discussed in relation to the search for an aetiological model of stereotypy
New Research Questions Statin ‘Benefit’ In People At Low Risk Of Heart Disease - 25 January 2011
No full textNEW DELHI - Although clinical studies have suggested that the cholesterol lowering drugs known as statins could benefit people who are not already ill with cardiovascular disease, this assumption may have been premature - according to the author of a new Cochrane systematic review of the effects of statins. Shah Ebrahim explains to Peter Goodwin how many of the drugs-industry sponsored trials showing statin benefits have shortcomings, and that the cautious advice is to reserve statin therapy for patients who already have heart disease and those at risk of having a heart attack since the side effects of very widespread use of these drugs among healthy low-risk people are not yet fully known
Comparison of Polar® heart rate interval data with simultaneously recorded ECG signals in horses
No full textHuman heart rate monitors (HRMs) are frequently used in equine studies to measure heart rate (HR) and interbeat intervals (IBIs). However, to date, the most commonly used HRM (the Polar® system) in horses has not been validated against simultaneously recorded electrocardiogram (ECG) signals during a range of ambulatory conditions. Polar® S810i and ECG IBIs were simultaneously recorded from six horses under three conditions commonly included in behavioural observation: standing at rest, loose in the stable and at liberty in a field. Following recording, Polar® IBI data were corrected for error processing in cardiac data. Corrected and uncorrected Polar® data were then compared with simultaneously recorded ECG data using a variety of commonly measured time and frequency domain parameters (e.g. HR variability (HRV)). Polar® data collected while horses were stabled or in the field were significantly different from ECG data, even following correction of the data, and therefore, it may not be possible for the two systems to be used interchangeably. This study indicates the need for caution while using Polar® S810i for collecting HRV data, unless horses are stationary, and even when the IBI data are corrected for measurement error
A portable audio/video recorder for longitudinal study of child development
No full textCollection and analysis of ultra-dense, longitudinal observational data of child behavior in natural, ecologically valid, non-laboratory settings holds significant promise for advancing the understanding of child development and developmental disorders such as autism. To this end, we created the Speechome Recorder - a portable version of the embedded audio/video recording technology originally developed for the Human Speechome Project - to facilitate swift, cost-effective deployment in home environments. Recording child behavior daily in these settings will enable detailed study of developmental trajectories in children from infancy through early childhood, as well as typical and atypical dynamics of communication and social interaction as they evolve over time. Its portability makes possible potentially large-scale comparative study of developmental milestones in both neurotypical and developmentally delayed children. In brief, the Speechome Recorder was designed to reduce cost, complexity, invasiveness and privacy issues associated with naturalistic, longitudinal recordings of child development.National Institutes of Health (U.S.) (Grant R01 2DC007428)Nancy Lurie Marks Family Foundatio
Behavioural correlates of the equine stereotypy phenotype
No full textStereotypic behaviour is characterised as repetitive, topographically invariant, rigid behaviour patterns, often displayed by captive, domestic and laboratory animals. The cause of these behaviours is thought primarily to be related to impoverished or species-atypical living environments, but recent research has outlined a neural phenotype, relating to basal ganglia dopamine physiology, which is common to several species. One species displaying the neural and associated behavioural phenotypes is the Horse. The purpose of this thesis was to explore, through behavioural assays, the behavioural phenotypes associated with endogenous basal ganglia dysfunction as a neural feature of equine oral stereotypy. In the first study, the behavioural effects of one aspect of the neural phenotype – downregualtion of dopamine transmission in the nigrostriatal pathways – were examined. Animals with the medial aspect of the dorsal striatum lesioned have been shown to exhibit learning differences in spatial navigation procedures. Employing two dry-maze procedures, stereotypic and control horses were required to locate food in different locations. No specific differences between the groups were found, but the stereotypic group were found to be less exploratory and tended to adopt ‘habitual’ response patterns. In the next studies, the behavioural effects of a further feature of the neural phenotype – upregulation of mesoaccumbens dopamine transmission – were examined. Chronic amphetamine exposure leads to a similar neural phenotype, and this offered an interesting hypothesis in the context of the endogenous change reported in stereotypic horses. A Pavlovian to Instrumental Transfer task was initially employed, in which horses were first trained in a Pavolvian procedure, and subsequently trained to perform an instrumental response, reinforced by the same food as in the Pavlovian phase. In the transfer phase, the Pavlovian conditioned stimulus was introduced in the context of the instrumental responding. It was predicted that response rates would increase during the transfer phase; however, the results were inconclusive. In the third study, further behavioural effects of increased mesoaccumbens dopamine were tested by employing an instrumental choice procedure. Stereotypic horses and controls were trained to choose between two mutually-exclusive schedules of reinforcement, one associated with a short delay to gain food and one with a longer delay. Chronic amphetamine exposure leads to a decrease in sensitivity to delay, and it was demonstrated that stereotypic horses showed similar patterns, failing to choose the shorter schedule. Finally, increased dopamine transmission is known to enhance the rate at which learning shifts from planned-action to habit, and this was examined in stereotypic horses using a ‘place-response’ preparation. Evidence was found to support this hypothesis in two variations of this procedure. The latter findings suggested an imbalance of the constituent cells that form the striatum: the striosome and matrix components. Taking this in conjunction with the other findings, this imbalance may hold the key to identifying the aetiology of stereotypic behaviour
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