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| Author | Fenton, B.; Ratcliffe, J. | ||||
| Title | Animal behaviour: eavesdropping on bats | Type | Journal Article | ||
| Year | 2004 | Publication | Nature | Abbreviated Journal | Nature |
| Volume | 429 | Issue | 6992 | Pages  |
612-613 |
| Keywords | Acoustics; Animals; Chiroptera/anatomy & histology/classification/genetics/*physiology; Echolocation/*physiology; *Evolution; Phylogeny; Predatory Behavior/physiology; Species Specificity | ||||
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| Language | English | Summary Language | Original Title | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1476-4687 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:15190335 | Approved | no | ||
| Call Number | refbase @ user @ | Serial | 500 | ||
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| Author | De Stoppelaire, G.H.; Gillespie, T.W.; Brock, J.C.; Tobin, G.A. | ||||
| Title | Use of remote sensing techniques to determine the effects of grazing on vegetation cover and dune elevation at Assateague Island National Seashore: impact of horses | Type | Journal Article | ||
| Year | 2004 | Publication | Environmental Management | Abbreviated Journal | Environ Manage |
| Volume | 34 | Issue | 5 | Pages |
642-649 |
| Keywords | Animals; Animals, Wild; Conservation of Natural Resources; Ecosystem; Environmental Monitoring; *Feeding Behavior; *Horses; Maryland; Plants/*growth & development; Population Dynamics; Silicon Dioxide; *Soil | ||||
| Abstract | The effects of grazing by feral horses on vegetation and dune topography at Assateague Island National Seashore were investigated using color-infrared imagery, lidar surveys, and field measurements. Five pairs of fenced and unfenced plots (300 m2) established in 1993 on sand flats and small dunes with similar elevation, topography, and vegetation cover were used for this study. Color-infrared imagery from 1998 and field measurements from 2001 indicated that there was a significant difference in vegetation cover between the fenced and unfenced plot-pairs over the study period. Fenced plots contained a higher percentage of vegetation cover that was dominated by American beachgrass (Ammophila breviligulata). Lidar surveys from 1997, 1999, and 2000 showed that there were significant differences in elevation and topography between fenced and unfenced plot-pairs. Fenced plots were, on average, 0.63 m higher than unfenced plots, whereas unfenced plots had generally decreased in elevation after establishment in 1993. Results demonstrate that feral horse grazing has had a significant impact on dune formation and has contributed to the erosion of dunes at Assateague Island. The findings suggest that unless the size of the feral horse population is reduced, grazing will continue to foster unnaturally high rates of dune erosion into the future. In order to maintain the natural processes that historically occurred on barrier islands, much larger fenced exclosures would be required to prevent horse grazing. | ||||
| Address | US Geological Survey, Center for Coastal and Watershed Studies, St. Petersburg, Florida 33701, USA. georgia.destoppelaire@my.FWC.com | ||||
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| Language | English | Summary Language | Original Title | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0364-152X | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:15633024 | Approved | no | ||
| Call Number | Serial | 1896 | |||
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| Author | Sarter, M. | ||||
| Title | Animal cognition: defining the issues | Type | Journal Article | ||
| Year | 2004 | Publication | Neuroscience and Biobehavioral Reviews | Abbreviated Journal | Neurosci Biobehav Rev |
| Volume | 28 | Issue | 7 | Pages |
645-650 |
| Keywords | Animals; Behavior, Animal/*physiology; Cognition/*physiology; Humans; *Models, Animal; Psychopharmacology/methods; Reproducibility of Results | ||||
| Abstract | The assessment of cognitive functions in rodents represents a critical experimental variable in many research fields, ranging from the basic cognitive neurosciences to psychopharmacology and neurotoxicology. The increasing use of animal behavioral tests as 'assays' for the assessment of effects on learning and memory has resulted in a considerable heterogeneity of data, particularly in the field of behavioral and psycho pharmacology. The limited predictive validity of changes in behavioral performance observed in standard animal tests of learning and memory indicates that a renewed effort to scrutinize the validity of these tests is warranted. In humans, levels of processing (effortful vs. automatic) and categories of information (procedural vs. episodic/declarative) are important variables of cognitive operations. The design of tasks that assess the recall of 'episodic' or 'declarative' information appears to represent a particular challenge for research using laboratory rodents. For example, the hypothesis that changes in inspection time for a previously encountered place or object are based on the recall of declarative/episodic information requires substantiation. In order to generalize findings on the effects of neuronal or pharmacological manipulations on learning and memory, obtained from one species and one task, to other species and other tasks, the mediating role of important sets of variables which influence learning and memory (e.g. attentional, affective) needs to be determined. Similar to the view that a neuronal manipulation (e.g. a lesion) represents a theory of the condition modeled (e.g. a degenerative disorder), an animal behavioral task represents a theory of the behavioral/cognitive process of interest. Therefore, the test of hypotheses regarding the validity of procedures used to assess cognitive functions in animals is an inherent part of the research process. | ||||
| Address | Department of Psychology, University of Michigan, 4032 East Hall, 525 E. University Avenue, Ann Arbor, MI 48109-1109, USA. msarter@umich.edu | ||||
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| Language | English | Summary Language | Original Title | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0149-7634 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:15555674 | Approved | no | ||
| Call Number | Equine Behaviour @ team @ | Serial | 2804 | ||
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| Author | Pickens, C.L.; Holland, P.C. | ||||
| Title | Conditioning and cognition | Type | Journal Article | ||
| Year | 2004 | Publication | Neuroscience and Biobehavioral Reviews | Abbreviated Journal | Neurosci Biobehav Rev |
| Volume | 28 | Issue | 7 | Pages |
651-661 |
| Keywords | Animals; Association Learning/physiology; Cognition/*physiology; Conditioning (Psychology)/*physiology; Discrimination Learning/physiology; Humans; Memory; Models, Psychological; Reinforcement (Psychology); Visual Perception/physiology | ||||
| Abstract | Animals' abilities to use internal representations of absent objects to guide adaptive behavior and acquire new information, and to represent multiple spatial, temporal, and object properties of complex events and event sequences, may underlie many aspects of human perception, memory, and symbolic thought. In this review, two classes of simple associative learning tasks that address these core cognitive capacities are discussed. The first set, including reinforcer revaluation and mediated learning procedures, address the power of Pavlovian conditioned stimuli to gain access, through learning, to representations of upcoming events. The second set of investigations concern the construction of complex stimulus representations, as illustrated in studies of contextual learning, the conjunction of explicit stimulus elements in configural learning procedures, and recent studies of episodic-like memory. The importance of identifying both cognitive process and brain system bases of performance in animal models is emphasized. | ||||
| Address | Department of Psychological and Brain Sciences, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218, USA | ||||
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| Language | English | Summary Language | Original Title | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0149-7634 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:15555675 | Approved | no | ||
| Call Number | Equine Behaviour @ team @ | Serial | 2803 | ||
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| Author | Geisbauer, G.; Griebel, U.; Schmid, A.; Timney, B | ||||
| Title | Brightness discrimination and neutral point | Type | Journal Article | ||
| Year | 2004 | Publication | Canadian Journal of Zoology | Abbreviated Journal | Can. J. Zool |
| Volume | 82 | Issue | 4 | Pages |
660-670 |
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| Abstract | Abstract: Equine brightness discrimination ability and color discrimination were measured using a two-choice discrimination task. Two Haflinger horses (Equus caballus L., 1758) were trained to discriminate 30 different shades of grey varying from low to high relative brightness. Their ability to distinguish shades of grey was poor, with calculated Weber fractions of 0.42 and 0.45. In addition, a “neutral point” test to determine the dimensionality of color vision was carried out. Three hues of blue-green were tested versus a range of grey targets with brightnesses similar to those of the blue-green targets. A neutral point was found at about 480 nm. Thus, we can conclude that horses possess dichromatic color vision. |
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| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Equine Behaviour @ team @ | Serial | 3649 | ||
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| Author | Peham, C.; Licka, T.; Schobesberger, H.; Meschan, E. | ||||
| Title | Influence of the rider on the variability of the equine gait | Type | Journal Article | ||
| Year | 2004 | Publication | Human Movement Science | Abbreviated Journal | European Workshop on Movement Science |
| Volume | 23 | Issue | 5 | Pages |
663-671 |
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| Abstract | The aim of this study was to show that the motion pattern of a well-ridden horse varies less than the motion pattern of an unridden horse. In order to do so, we recorded the motion of two markers, one attached to the dorsal spinous processus of lumbar vertebra L4, the other to the right fore hoof. In total, we measured 21 horses in trot, ridden and unridden, with a fitting and with a non-fitting saddle. After breaking down the entire time series of the three-dimensional motion of the markers into their respective motion cycles, we computed a measure of motion pattern variability for the motion as well as for the derivatives (velocity and acceleration) along each of the three principal dimensions. Two of six variables (velocity and acceleration in the forward direction) displayed a significant discrimination between the ridden and the unridden case, and demonstrated the beneficial effect of a rider on the horse's motion pattern variability. Saddle fit was shown to have also an influence on motion variability: variability of two variables (velocity and of acceleration in forward direction) was significantly lower with a fitting saddle compared to a non-fitting saddle, a third variable (acceleration in the transversal direction) showed a significant difference also. This new method offers an objective evaluation of saddle fit, and a sensitive assessment of the quality of the rider in the moving horse. | ||||
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| Notes | Approved | no | |||
| Call Number | Equine Behaviour @ team @ | Serial | 3670 | ||
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| Author | Dutto, D.J.; Hoyt, D.F.; Clayton, H.M.; Cogger, E.A.; Wickler, S.J. | ||||
| Title | Moments and power generated by the horse (Equus caballus) hind limb during jumping | Type | Journal Article | ||
| Year | 2004 | Publication | The Journal of Experimental Biology | Abbreviated Journal | J Exp Biol |
| Volume | 207 | Issue | Pt 4 | Pages |
667-674 |
| Keywords | Animals; Biomechanics; Hindlimb/*physiology; Horses/*physiology; Locomotion/*physiology | ||||
| Abstract | The ability to jump over an obstacle depends upon the generation of work across the joints of the propelling limb(s). The total work generated by one hind limb of a horse and the contribution to the total work by four joints of the hind limb were determined for a jump. It was hypothesized that the hip and ankle joints would have extensor moments performing positive work, while the knee would have a flexor moment and perform negative work during the jump. Ground reaction forces and sagittal plane kinematics were simultaneously recorded during each jumping trial. Joint moment, power and work were determined for the metatarsophalangeal (MP), tarsal (ankle), tibiofemoral (knee) and coxofemoral (hip) joints. The hip, knee and ankle all flexed and then extended and the MP extended and then flexed during ground contact. Consistent with our hypothesis, large extensor moments were observed at the hip and ankle joints and large flexor moments at the knee and MP joints throughout ground contact of the hind limb. Peak moments tended to occur earlier in stance in the proximal joints but peak power generation of the hind limb joints occurred at similar times except for the MP joint, with the hip and ankle peaking first followed by the MP joint. During the first portion of ground contact (approximately 40%), the net result of the joint powers was the absorption of power. During the remainder of the contact period, the hind limb generated power. This pattern of power absorption followed by power generation paralleled the power profiles of the hip, ankle and MP joints. The total work performed by one hind limb was 0.71 J kg(-1). Surprisingly, the knee produced 85% of the work (0.60 J kg(-1)) done by the hind limb, and the positive work performed by the knee occurred during the first 40% of the take-off. There is little net work generated by the other three joints over the entire take-off. Velocity of the tuber coxae (a landmark on the pelvis of the animal) was negative (downward) during the first 40% of stance, which perhaps reflects the negative work performed to decrease the potential energy during the first 40% of contact. During the final 60% of contact, the hip, ankle and MP joints generate positive work, which is reflected in the increase of the animal's potential energy. | ||||
| Address | Department of Kinesiology and Health Promotion, California State Polytechnic University, Pomona, CA 91768, USA. ddutto@csupomona.edu | ||||
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| Language | English | Summary Language | Original Title | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0022-0949 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:14718509 | Approved | no | ||
| Call Number | Equine Behaviour @ team @ | Serial | 3654 | ||
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| Author | Rollot, Y.; Lecuyer, E.; Chateau, H.; Crevier-Denoix, N. | ||||
| Title | Development of a 3D model of the equine distal forelimb and of a GRF shoe for noninvasive determination of in vivo tendon and ligament loads and strains | Type | Journal Article | ||
| Year | 2004 | Publication | Equine Veterinary Journal | Abbreviated Journal | Equine Vet J |
| Volume | 36 | Issue | 8 | Pages |
677-682 |
| Keywords | Animals; Biomechanics; Floors and Floorcoverings; Forelimb/*physiology/ultrasonography; Gait/physiology; Horses/*physiology; Image Processing, Computer-Assisted; Imaging, Three-Dimensional/methods/*veterinary; Ligaments, Articular/*physiology; Locomotion/*physiology; Models, Biological; Shoes; Tendons/*physiology; Toe Joint/physiology/ultrasonography | ||||
| Abstract | REASONS FOR PERFORMING STUDY: As critical locomotion events (e.g. high-speed and impacts during racing, jump landing) may contribute to tendinopathies, in vivo recording of gaits kinematic and dynamic parameters is essential for 3D reconstruction and analysis. OBJECTIVE: To propose a 3D model of the forelimb and a ground reaction force recording shoe (GRF-S) for noninvasively quantifying tendon and ligament loads and strains. METHODS: Bony segments trajectories of forelimbs placed under a power press were recorded using triads of ultrasonic kinematic markers linked to the bones. Compression cycles (from 500-6000 N) were applied for different hoof orientations. Locations of tendon and ligament insertions were recorded with regard to the triads. The GRF-S recorded GRF over the hoof wall and used four 3-axis force sensors sandwiched between a support shoe and the shoe to be tested. RESULTS: Validation of the model by comparing calculated and measured superficial digital flexor tendon strains, and evaluation of the role of proximal interphalangeal joint in straight sesamoidean ligament and oblique sesamoidean ligament strains, were successfully achieved. Objective comparisons of the 3 components of GRF over the hoof for soft and hard grounds could be recorded, where the s.d. of GRF norm was more important on hard ground at walk and trot. CONCLUSIONS: Soft grounds (sand and rubber) dissipate energy by lowering GRF amplitude and diminish bounces and vibrations at impact. At comparable speed, stance phase was longer on soft sand ground. POTENTIAL RELEVANCE: The conjugate use of the GRF-S and the numerical model would help to quantify and analyse ground/shoe combination on comfort, propulsion efficiency or lameness recovery. | ||||
| Address | UMR INRA-ENVA de Biomecanique et Pathologie Locomotrice du Cheval, Ecole Nationale Veterinaire d'Alfort, 7, Avenue du General de Gaulle, 94704 Maisons-Alfort, France | ||||
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| Language | English | Summary Language | Original Title | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0425-1644 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:15656495 | Approved | no | ||
| Call Number | Equine Behaviour @ team @ | Serial | 3769 | ||
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| Author | Davies, H.M.S.; Merritt, J.S. | ||||
| Title | Surface strains around the midshaft of the third metacarpal bone during turning | Type | Journal Article | ||
| Year | 2004 | Publication | Equine Veterinary Journal | Abbreviated Journal | Equine Veterinary Journal |
| Volume | 36 | Issue | 8 | Pages |
689-692 |
| Keywords | horse; exercise; strain; third metacarpal bone; turns | ||||
| Abstract | Summary Reasons for performing study: Bone strains quantify skeletal effects of specific exercise and hence assist in designing training programmes to avoid bone injury. Objective: To test whether compressive strains increase on the lateral surface of the inside third metacarpal bone (McIII) and the medial surface of the outside McIII in a turn. Methods: Rosette strain gauges on dorsal, medial and lateral surfaces of the midshaft of the left McIII in 2 Thoroughbred geldings were recorded simultaneously during turning at the walk on a bitumen surface. Results: Medial surface: Compression peaks were larger in the outside limb. Tension peaks were larger in the inside limb and in a tighter turn. On the lateral surface compression and tension peaks were larger on the inside limb, which showed the largest recorded strains (compression of -1400 microstrains). Dorsal compression strains were larger on the outside limb and on a larger circle. Tensile strains were similar in both directions and larger on a larger circle. Conclusions: Compressive strains increased on the lateral surface of the inside McIII and medial surface of the outside McIII in a turn. Potential relevance: Slow-speed turning exercise may be sufficient to maintain bone mechanical characteristics in the inside limb lateral McIII cortex. Further work is needed to confirm these findings and to determine whether faster gaits and/or tighter turns are sufficient to cause bone modelling levels of strain in the medial and lateral McIII cortex. | ||||
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| Publisher | American Medical Association (AMA) | Place of Publication | Editor | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0425-1644 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Equine Behaviour @ team @ | Serial | 6715 | ||
| Permanent link to this record | |||||
| Author | Griffiths,S. W.; Brockmark, S.; Höjesjö,J.; Johnsson,J. I. | ||||
| Title | Coping with divided attention: the advantage of familiarity | Type | Journal Article | ||
| Year | 2004 | Publication | Proceedings of the Royal Society B: Biological Sciences | Abbreviated Journal | Proc. Roy. Soc. Lond. B Biol. Sci. |
| Volume | 271 | Issue | 1540 | Pages |
695-699 |
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| Abstract | The ability of an animal to perform a task successfully is limited by the amount of attention being simultaneously focused on other activities. One way in which individuals might reduce the cost of divided attention is by preferentially focusing on the most beneficial tasks. In territorial animals where aggression is lower among familiar individuals, the decision to associate preferentially with familiar conspecifics may therefore confer advantages by allowing attention to be switched from aggression to predator vigilance and feeding. Wild juvenile brown trout were used to test the prediction that familiar fishes respond more quickly than unfamiliar fishes to a simulated predator attack. Our results confirm this prediction by demonstrating that familiar trout respond 14% faster than unfamiliar individuals to a predator attack. The results also show that familiar fishes consume a greater number of food items, foraging at more than twice the rate of unfamiliar conspecifics. To the best of our knowledge, these results provide the first evidence that familiarity–biased association confers advantages through the immediate fitness benefits afforded by faster predator–evasion responses and the long–term benefits provided by increased feeding opportunities. | ||||
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| Notes | 10.1098/rspb.2003.2648 | Approved | no | ||
| Call Number | Equine Behaviour @ team @ | Serial | 5007 | ||
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