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Corr, J.A. |
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Title |
Nuns and monkeys: investigating the behavior of our oldest old |
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Journal Article |
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Year |
2004 |
Publication |
Science of Aging Knowledge Environment : SAGE KE |
Abbreviated Journal |
Sci Aging Knowledge Environ |
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Volume |
2004 |
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41 |
Pages |
pe38 |
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Aged; Aged, 80 and over/*physiology; Aging/*physiology; Animals; Behavior/*physiology; Humans; Macaca mulatta |
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The use of nonhuman primates, particularly rhesus macaques (Macaca mulatta), as the best model for human physiological and cognitive aging is broadly accepted. Studies employing nonhuman primates to investigate behavioral changes that may occur with increasing age, however, are not common mostly because of the unavailability of appropriate subjects. Recent longitudinal human studies suggest that individual personality might play a large role in aging “successfully” and in the retention of high levels of cognition into old age. As a result of the demographic trend of increasing numbers of aged monkeys and apes in captivity, an opportunity exists to further investigate behavioral aging using the monkey model. |
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Department of Anthropology, Grand Valley State University, Allendale, MI 49401, USA. corrj@gvsu.edu |
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1539-6150 |
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PMID:15483334 |
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Equine Behaviour @ team @ |
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2828 |
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Author |
Landsberg, G.; Araujo, J.A. |
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Title |
Behavior problems in geriatric pets |
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Journal Article |
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Year |
2005 |
Publication |
The Veterinary Clinics of North America. Small Animal Practice |
Abbreviated Journal |
Vet Clin North Am Small Anim Pract |
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35 |
Issue |
3 |
Pages |
675-698 |
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Aging/*pathology/physiology/*psychology; Animals; *Behavior, Animal; Cats/*physiology/psychology; Cognition/physiology; Diagnosis, Differential; Dogs/*physiology/psychology; Preventive Medicine |
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Aging pets often suffer a decline in cognitive function (eg, memory,learning, perception, awareness) likely associated with age-dependent brain alterations. Clinically, cognitive dysfunction may result in various behavioral signs, including disorientation; forgetting of previously learned behaviors, such as house training; alterations in the manner in which the pet interacts with people or other pets;onset of new fears and anxiety; decreased recognition of people, places, or pets; and other signs of deteriorating memory and learning ability. Many medical problems, including other forms of brain pathologic conditions, can contribute to these signs. The practitioner must first determine the cause of the behavioral signs and then determine an appropriate course of treatment, bearing in mind the constraints of the aging process. A diagnosis of cognitive dysfunction syndrome is made once other medical and behavioral causes are ruled out. |
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Doncaster Animal Clinic, 99 Henderson Avenue, Thornhill, Ontario L3T2K9, Canada. gmlandvm@aol.com |
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0195-5616 |
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PMID:15833565 |
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Equine Behaviour @ team @ |
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2855 |
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Author |
Dyson, S.; Murray, R. |
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Title |
Pain associated with the sacroiliac joint region: a clinical study of 74 horses |
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Journal Article |
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Year |
2003 |
Publication |
Equine Veterinary Journal |
Abbreviated Journal |
Equine Vet J |
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35 |
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3 |
Pages |
240-245 |
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Keywords |
Age Factors; Analgesia/veterinary; Anesthetics, Local/pharmacology; Animals; Body Height; Body Weight; Breeding; Female; Forelimb; Gait; Hindlimb; Horse Diseases/*diagnosis/radionuclide imaging; Horses; Lameness, Animal/*physiopathology; Lumbar Vertebrae/physiopathology; Male; Pain/diagnosis/drug therapy/radionuclide imaging/*veterinary; Sacroiliac Joint/*physiopathology; Sacrum/physiopathology |
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REASONS FOR PERFORMING STUDY: There has been no large study of horses with suspected sacroiliac (SI) joint region pain in which the clinical diagnosis has been supported by either abnormal radiopharmaceutical activity in the SI joint region or by periarticular infiltration of local anaesthetic solution. OBJECTIVES: To describe the clinical features of horses with SI joint region pain, to document the age, breed, sex, discipline, size and conformation of affected horses and to compare these with the author's (SD) normal case population and to document the results of infiltration of local anaesthetic solution around the SI joint region. METHODS: Horses were selected for inclusion in the study based upon the exclusion of other causes of lameness or poor performance, together with clinical signs suggestive of SI joint pain and abnormal radiopharmaceutical activity in the SI joint region and/or a positive response to periarticular infiltration of local anaesthetic solution. RESULTS: Sacroiliac joint region disease was identified in 74 horses between November 1997 and March 2002. Dressage and showjumping horses appeared to be at particular risk (P < 0.001). Affected horses were generally slightly older than the normal clinic population (P < 0.0001), taller at the withers (P < 0.0001) and of greater bodyweight (P < 0.01). There was a significant effect of breed (P < 0.001), with a substantially higher proportion of Warmblood horses (51%) in the SI pain group compared to the normal clinic population (29%). There was no correlation between conformation and the presence of SI joint region pain. The tubera sacrale appeared grossly symmetrical in most (95%) horses. Poor development of the epaxial muscles in the thoracolumbar region and asymmetry of the hindquarter musculature were common. Twenty-six horses (35%) showed restricted flexibility of the thoracolumbar region and 10 (16%) had an exaggerated response to pressure applied over the tubera sacrale. Fourteen horses (19%) were reluctant to stand on one hindlimb for prolonged periods. The majority of horses (75%) had a straight hindlimb flight and only 18% moved closely behind or plaited. In all horses restricted hindlimb impulsion was the predominant feature; invariably this was most obvious when the horse was ridden. Stiffness, unwillingness to work on the bit and poor quality canter were common. Sacroiliac joint region pain was seen alone (47%), or in conjunction with thoracolumbar pain (16%), hindlimb lameness (20%), forelimb lameness (7%) or a combination of problems (10%). Seventy-three horses (99%) had abnormalities of the SI joint region identified using nuclear scintigraphy. Infiltration of local anaesthetic solution around the SI joint region produced profound improvement in gait in all 34 horses in which it was performed. CONCLUSIONS AND POTENTIAL RELEVANCE: Careful clinical examination combined with scintigraphic evaluation of the SI joint region and local analgesia can enable a more definitive diagnosis of SI joint region pain than has previously been possible. |
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Centre for Equine Studies, Animal Health Trust, Lanwades Park, Kentford, Newmarket, Suffolk CB8 7UU, UK |
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0425-1644 |
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PMID:12755425 |
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Equine Behaviour @ team @ |
Serial |
3723 |
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Author |
Herholz, C.P.; Gerber, V.; Tschudi, P.; Straub, R.; Imhof, A.; Busato, A. |
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Use of volumetric capnography to identify pulmonary dysfunction in horses with and without clinically apparent recurrent airway obstruction |
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Journal Article |
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Year |
2003 |
Publication |
American Journal of Veterinary Research |
Abbreviated Journal |
Am J Vet Res |
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Volume |
64 |
Issue |
3 |
Pages |
338-345 |
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Keywords |
Aging; Airway Obstruction/*complications/diagnosis/*veterinary; Animals; Capnography/*methods/*veterinary; Female; Horse Diseases/*diagnosis; Horses; Lung Diseases/complications/*diagnosis/*veterinary; Male; Predictive Value of Tests |
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OBJECTIVE: To investigate whether volumetric capnography indices could be used to differentiate between horses without recurrent airway obstruction (RAO) and horses with RAO that were in clinical remission or that had clinically apparent RAO. ANIMALS: 70 adult Swiss Warmblood horses (20 used for pleasure riding and 50 used for dressage or show jumping). PROCEDURE: Horses were allocated to 4 groups on the basis of history, clinical signs, results of endoscopy, and cytologic findings (group 1, 21 healthy horses; group 2, 22 horses with RAO that were in remission; group 3, 16 horses with mild RAO; group 4, 11 horses with exacerbated RAO). Expiratory volume and CO2 curves were recorded by use of a computerized ultrasonic spirometer. Volumetric capnograms were plotted, and derived indices were calculated. RESULTS: Dead-space volume (VD) was calculated by use of the Bohr equation (VD(Bohr)) and for physiologic VD (VD(phys)). Ratios for VD(Bohr) to expiratory tidal volume (VT) and VD(phys) to V(T) as well as an index of effective CO2 elimination were significantly different among groups of horses. Age and use of the horses also significantly affected volumetric capnography indices. CONCLUSIONS AND CLINICAL RELEVANCE: Ratios of VD(Bohr) to VT and VD(phys) to VT as well as an index of effective CO2 elimination were sufficiently sensitive measures to distinguish between healthy horses and horses with RAO in remission. To optimize the ability of volumetric capnography indices to differentiate among horses in heterogeneous populations, it is important to account for effects of age and specific use of the horses. |
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Department of Equine Internal Medicine, Faculty of Veterinary Medicine, University of Berne, Langgasstr 124, CH-3012 Berne, Switzerland |
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0002-9645 |
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PMID:12661875 |
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Equine Behaviour @ team @ |
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3724 |
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Author |
Young, L.E.; Rogers, K.; Wood, J.L.N. |
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Left ventricular size and systolic function in Thoroughbred racehorses and their relationships to race performance |
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Journal Article |
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Year |
2005 |
Publication |
Journal of Applied Physiology (Bethesda, Md. : 1985) |
Abbreviated Journal |
J Appl Physiol |
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99 |
Issue |
4 |
Pages |
1278-1285 |
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*Adaptation, Physiological; Aging/physiology; Animal Husbandry; Animals; *Echocardiography; Female; Heart/*physiology; Heart Ventricles; Horses/*physiology; Male; *Physical Conditioning, Animal; Running/*physiology; Stroke Volume; Systole; Task Performance and Analysis |
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Cardiac morphology in human athletes is known to differ, depending on the sports-specific endurance component of their events, whereas anecdotes abound about superlative athletes with large hearts. As the heart determines stroke volume and maximum O(2) uptake in mammals, we undertook a study to test the hypothesis that the morphology of the equine heart would differ between trained horses, depending on race type, and that left ventricular size would be greatest in elite performers. Echocardiography was performed in 482 race-fit Thoroughbreds engaged in either flat (1,000-2,500 m) or jump racing (3,200-6,400 m). Body weight and sex-adjusted measures of left ventricular size were largest in horses engaged in jump racing over fixed fences, compared with horses running shorter distances on the flat (range 8-16%). The observed differences in cardiac morphologies suggest that subtle differences in training and competition result in cardiac adaptations that are appropriate to the endurance component of the horses' event. Derived left ventricular mass was strongly associated with published rating (quality) in horses racing over longer distances in jump races (P < or = 0.001), but less so for horses in flat races. Rather, left ventricular ejection fraction and left ventricular mass combined were positively associated with race rating in older flat racehorses running over sprint (<1,408 m) and longer distances (>1,408 m), explaining 25-35% of overall variation in performance, as well as being closely associated with performance in longer races over jumps (23%). These data provide the first direct evidence that cardiac size influences athletic performance in a group of mammalian running athletes. |
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Centre for Equine Studies, Animal Health Trust, Newmarket, Suffolk, UK. lesley.young@aht.org.uk |
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8750-7587 |
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PMID:15920096 |
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Equine Behaviour @ team @ |
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3768 |
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Rollot, Y.; Lecuyer, E.; Chateau, H.; Crevier-Denoix, N. |
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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 |
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Journal Article |
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Year |
2004 |
Publication |
Equine Veterinary Journal |
Abbreviated Journal |
Equine Vet J |
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Volume |
36 |
Issue |
8 |
Pages |
677-682 |
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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 |
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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. |
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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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0425-1644 |
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PMID:15656495 |
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Equine Behaviour @ team @ |
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3769 |
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Cassiat, G.; Pourcelot, P.; Tavernier, L.; Geiger, D.; Denoix, J.M.; Degueurce, D. |
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Influence of individual competition level on back kinematics of horses jumping a vertical fence |
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Journal Article |
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Year |
2004 |
Publication |
Equine Veterinary Journal |
Abbreviated Journal |
Equine Vet J |
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Volume |
36 |
Issue |
8 |
Pages |
748-753 |
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Animals; Back/*physiology; Biomechanics; Female; Forelimb/*physiology; Gait/*physiology; Hindlimb/*physiology; Horses/*physiology; Image Processing, Computer-Assisted; Imaging, Three-Dimensional/veterinary; Locomotion/physiology; Male; Video Recording |
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REASONS FOR PERFORMING STUDY: The costs and investments required for the purchase and training of showjumpers justify the need to find selection means for jumping horses. Use of objective kinematic criteria correlated to jumping ability could be helpful for this assessment. OBJECTIVES: To compare back kinematics between 2 groups of horses of different competition levels (Group 1, competing at high level; Group 2 competing at low level) while free jumping over a 1 m vertical fence. METHODS: Three-dimensional recordings were performed using 2 panning cameras. Kinematic parameters of the withers and tuber sacrale (vertical displacement, vertical and horizontal velocities), backline inclination and flexion-extension motion of the 3 main dorsal segments (thoracic, thoracolumbar and lumbosacral) were analysed. RESULTS: Group 2 horses had a lower displacement of their withers and tuber sacrale from the end of the last approach stride until the first departure stride (P<0.05). As a result, they increased the flexion of their thoracolumbar and lumbosacral junctions during the hindlimb swing phase before take-off (P<0.05). However, withers and tuber sacrale velocities were slightly modified. Group 1 horses pitched their backline less forward during the forelimb stance phase before take-off and straightened it more after landing (P<0.05), probably indicating a more efficient strutting action of their forelimbs. CONCLUSIONS AND POTENTIAL RELEVANCE: Because significant differences in back motion were found between good and poor jumpers when jumping a 1 m high fence, criteria based on certain back kinematics can be developed that may help in the selection of talented showjumpers. |
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UMR INRA-ENVA de Biomecanique et Pathologie Locomotrice du Cheval, Ecole Nationale Veterinaire d'Alfort, Avenue du General de Gaulle, 94704 Maisons Alfort, France |
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0425-1644 |
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PMID:15656509 |
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Equine Behaviour @ team @ |
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4042 |
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Templeton, J.J.; Giraldeau, L.-A. |
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Vicarious sampling: the use of personal and public information by starlings foraging in a simple patchy environment |
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Journal Article |
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Year |
1996 |
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Behavioral Ecology and Sociobiology |
Abbreviated Journal |
Behav. Ecol. Sociobiol. |
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38 |
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2 |
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105-114 |
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Social foraging ? Patch sampling ? Public information ? Sturnidae |
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Group foragers may be able to assess patch quality more efficiently by paying attention to the sampling activities of conspecifics foraging in the same patch. In a previous field experiment, we showed that starlings foraging on patches of hidden food could use the successful foraging activities of others to help them assess patch quality. In order to determine whether a starling could also use another individual's lack of foraging success to assess and depart from empty patches more quickly, we carried out two experimental studies which compared the behaviour of captive starlings sampling artificial patches both when alone and when in pairs. Solitary starlings were first trained to assess patch quality in our experimental two-patch system, and were then tested on an empty patch both alone and with two types of partner bird. One partner sampled very few holes and thus provided a low amount of public information; the other sampled numerous holes and thus provided a high amount of public information. In experiment 1, we found no evidence of vicarious sampling. Subjects sampled a similar number of empty holes when alone as when with the low and high information partners; thus they continued to rely on their own personal information to make their patch departure decisions. In experiment 2, we modified the experimental patches, increasing the ease with which a bird could watch another's sampling activities, and increasing the difficulty of acquiring accurate personal sampling information. This time, subjects apparently did use public information, sampling fewer empty holes before departure when with the high-information partner than when with the low-information partner, and sampling fewer holes when with the low-information partner than when alone. We suggest that the degree to which personal and public information are used is likely to depend both on a forager's ability to remember where it has already sampled and on the type of environment in which foraging takes place. |
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Equine Behaviour @ team @ |
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4198 |
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Fleurance, G.; Duncan, P.; Fritz, H.; Cabaret, J.; Cortet, J.; Gordon, I.J. |
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Selection of feeding sites by horses at pasture: Testing the anti-parasite theory |
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Journal Article |
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2007 |
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Applied Animal Behaviour Science |
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Appl. Anim. Behav. Sci. |
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108 |
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3-4 |
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228-301 |
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Foraging strategies; Horses; Parasite risk; Patch choice |
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Management of grazed grasslands for production and/or conservation objectives requires a thorough understanding of the choices of feeding sites by herbivores, and of the biological processes involved. Most models of the feeding strategies of herbivores are based on the principle that optimising the intake of energy (or some nutrient) is the primary goal of foragers but other selective forces, such as parasitism, could be important. Gastrointestinal parasites (including cyathostome nematodes) have powerful effects on the fitness of herbivores and may act as a major selection pressure favouring host behaviour that reduces the risk of encountering parasites. Among large herbivores, horses have perhaps the most marked tendency to select particular feeding sites within grasslands. We test here: (1) whether horses select feeding patches with relatively low parasite densities and (2) if their choice is affected by their parasite load. We used 10 two-year old saddle-horses and three periods. In the first period, the horses were under natural parasitism which varied strongly among individuals; in the second period they were all dewormed, and in the third, a sub-set of the horses was experimentally infected with cyathostome larvae. Ninety-eight percent of the infective larvae in the pasture were found <1 m from faeces. The main determinant of the choice of feeding patch by horses was the availability of patches of different parasite risk and grass height. Controlling for availability, the horses used tall grasses (>16 cm) less than expected, whether the grass was contaminated or not, and they selected for short patches >1 m from faeces, where the risk of encountering parasites was low. These results suggest that selection of feeding sites by horses is driven by an interaction between their nutritional and anti-parasite strategies: the horses avoid the patches of tall grass which are generally of low quality and areas contaminated by parasite larvae which leads them to prefer the patches of short grass far from faeces. The parasite status of the horses at the time of the experiment had no effect on their feeding choices. However, before concluding that the challenge by cyathostomes has no effect on the selection of feeding sites in horses, it will be necessary to test whether the history of parasitism of the individuals, rather than the current status, is important. |
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Equine Behaviour @ team @ |
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4228 |
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Valone, T.J. |
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Group foraging, public information, and patch estimation |
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1989 |
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Oikos |
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Oikos |
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56 |
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3 |
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357-363 |
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Techniques; Mathematical techniques; Nutrition; Feeding behaviour; Behaviour; Social behaviour^, Comprehensive Zoology; Mathematical model; Resource patch estimation by group members; use of public information; Foraging; Group behaviour |
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Abstract |
Public information is information about the quality of a patch that can be obtained by observing the foraging success of other individuals in that patch. I examine the influence of the use of public information on patch departure and foraging efficiency of group members. When groups depart a patch with the first individual to leave, the use of public information can prevent the underutilization of resource patches. |
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Equine Behaviour @ team @ |
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4274 |
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