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Author  |
Stahlbaum, C.C.; Houpt, K.A. |
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Title |
The role of the Flehmen response in the behavioral repertoire of the stallion |
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Journal Article |
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Year |
1989 |
Publication |
Physiology & behavior |
Abbreviated Journal |
Physiol. Behav. |
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Volume |
45 |
Issue |
6 |
Pages |
1207-1214 |
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Keywords |
Animals; Behavior, Animal/*physiology; Circadian Rhythm; Discrimination (Psychology)/physiology; Estrus; Feces; Female; Horses/*physiology; Male; Sexual Behavior, Animal/*physiology; Smell/*physiology; Taste/physiology; Urine |
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Abstract |
The role of the Flehmen response in equine behavior was investigated under field and laboratory conditions. In Experiment 1, a field study made of five stallions on pasture with between three and eighteen mares each during the season indicated the following: 1) The Flehmen response was most frequently preceded by nasal, rather than oral, investigation of substances; 2) The stallions' rate of Flehmen varied with the estrous cycles of the mares; 3) The rate of Flehmen response did not show a variation with time of day; and 4) The Flehmen response was most frequently followed by marking behaviors rather than courtship behaviors. The results suggest that the Flehmen response is not an immediate component of sexual behavior, e.g., courtship of the stallion but may be involved in the overall monitoring of the mare's estrous cycle. Therefore the Flehmen response may contribute to the chemosensory priming of the stallion for reproduction. In Experiment 2 stallions were presented with urine or feces of mares in various stages of the reproductive cycle as well as with their own or other males' urine or feces. The occurrence of sniffing and Flehmen was used to determine the discriminatory ability of the stallions. Stallions can differentiate the sex of a horse on the basis of its feces alone, but cannot differentiate on the basis of urine. This ability may explain the function of fecal marking behavior of stallions. |
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New York State College of Veterinary Medicine, Cornell University, Ithaca 14853 |
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0031-9384 |
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PMID:2813545 |
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refbase @ user @ |
Serial |
44 |
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Author |
Stahl, F.; Dorner, G. |
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Title |
Responses of salivary cortisol levels to stress-situations |
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Journal Article |
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Year |
1982 |
Publication |
Endokrinologie |
Abbreviated Journal |
Endokrinologie |
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Volume |
80 |
Issue |
2 |
Pages |
158-162 |
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Keywords |
Adrenocorticotropic Hormone/diagnostic use; Anxiety Disorders/metabolism; Circadian Rhythm; Cushing Syndrome/metabolism; Fear/physiology; Female; Humans; Hydrocortisone/*metabolism; Male; Pain/metabolism; Pregnancy; Saliva/*metabolism; Stress/*metabolism |
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Abstract |
A procedure is described for determining salivary cortisol levels by a competitive protein-binding assay using horse transcortin. The collection of saliva was performed by means of filter paper-strips. Filter paper samples are more than 5 days stable after air-drying. In this form, the samples could be stored without refrigerator or deep-freezer and, if necessary, sent by post to the laboratory without any special precaution. Stressful situation of either painful or anxious origin were associated with an adequate increase of salivary cortisol levels. The increases were 157 to 230% of the initial or normal values dependent on the kind of stress. The mean values in 4 cases of Cushing's syndrome were 380% and 1 hour after 25 I.U. ACTH 690% higher than those in normal persons. In normal persons, a well-defined circadian rhythm has been observed. |
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0013-7251 |
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PMID:6297880 |
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Call Number |
refbase @ user @ |
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4056 |
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Spadavecchia, C.; Arendt-Nielsen, L.; Spadavecchia, L.; Mosing, M.; Auer, U.; van den Hoven, R. |
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Title |
Effects of butorphanol on the withdrawal reflex using threshold, suprathreshold and repeated subthreshold electrical stimuli in conscious horses |
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Journal Article |
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Year |
2007 |
Publication |
Veterinary anaesthesia and analgesia |
Abbreviated Journal |
Vet Anaesth Analg |
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Volume |
34 |
Issue |
1 |
Pages |
48-58 |
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Keywords |
Analgesics, Opioid/pharmacology; Animals; Butorphanol/*pharmacology; Consciousness; Electric Stimulation; Electromyography; Female; Forelimb/physiology; Horses/*physiology; Male; Pain/veterinary; Pain Threshold/*drug effects; Reflex/*drug effects |
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OBJECTIVE: To assess the effects of a single intravenous dose of butorphanol (0.1 mg kg(-1)) on the nociceptive withdrawal reflex (NWR) using threshold, suprathreshold and repeated subthreshold electrical stimuli in conscious horses. STUDY DESIGN: 'Unblinded', prospective experimental study. ANIMALS: Ten adult horses, five geldings and five mares, mean body mass 517 kg (range 487-569 kg). METHODS: The NWR was elicited using single transcutaneous electrical stimulation of the palmar digital nerve. Repeated stimulations were applied to evoke temporal summation. Surface electromyography was performed to record and quantify the responses of the common digital extensor muscle to stimulation and behavioural reactions were scored. Before butorphanol administration and at fixed time points up to 2 hours after injection, baseline threshold intensities for NWR and temporal summation were defined and single suprathreshold stimulations applied. Friedman repeated-measures analysis of variance on ranks and Wilcoxon signed-rank test were used with the Student-Newman-Keul's method applied post-hoc. The level of significance (alpha) was set at 0.05. RESULTS: Butorphanol did not modify either the thresholds for NWR and temporal summation or the reaction scores, but the difference between suprathreshold and threshold reflex amplitudes was reduced when single stimulation was applied. Upon repeated stimulation after butorphanol administration, a significant decrease in the relative amplitude was calculated for both the 30-80 and the 80-200 millisecond intervals after each stimulus, and for the whole post-stimulation interval in the right thoracic limb. In the left thoracic limb a decrease in the relative amplitude was found only in the 30-80 millisecond epoch. CONCLUSION: Butorphanol at 0.1 mg kg(-1) has no direct action on spinal Adelta nociceptive activity but may have some supraspinal effects that reduce the gain of the nociceptive system. CLINICAL RELEVANCE: Butorphanol has minimal effect on sharp immediate Adelta-mediated pain but may alter spinal processing and decrease the delayed sensations of pain. |
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Anesthesiology Section, Department of Clinical Veterinary Sciences, Vetsuisse Faculty, University of Berne, Berne, Switzerland. claudia.spadavecchia@veths.no |
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1467-2987 |
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PMID:17238962 |
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no |
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Call Number |
refbase @ user @ |
Serial |
92 |
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Author |
Spadavecchia, C.; Arendt-Nielsen, L.; Andersen, O.K.; Spadavecchia, L.; Doherr, M.; Schatzmann, U. |
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Title |
Comparison of nociceptive withdrawal reflexes and recruitment curves between the forelimbs and hind limbs in conscious horses |
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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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64 |
Issue |
6 |
Pages |
700-707 |
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Keywords |
Animals; Consciousness; Female; Forelimb/*physiology; Hindlimb/*physiology; Horses/*physiology; Male; Nociceptors/physiology; Pain/*physiopathology/*veterinary; Pain Threshold/physiology; Recruitment, Neurophysiological/physiology; Reflex/*physiology |
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OBJECTIVE: To compare nociceptive withdrawal reflexes (NWRs) evoked from the distal aspect of the left forelimb and hind limb in conscious standing horses and to investigate NWR recruitment for graded electrical stimulation intensities. ANIMALS: 20 adult horses. PROCEDURE: Surface electromyographic (EMG) activity evoked by transcutaneous electrical stimulation of the digital palmar (or plantar) nerve was recorded from the common digital extensor and cranial tibial muscles. Stimuli consisted of 25-millisecond train-of-5 constant current pulses. Current intensity was gradually increased until NWR threshold intensity was reached. The EMG signal was analyzed for quantification of the NWR. Behavioral responses accompanying the reflex were scored (scale, 0 to 5). The NWR recruitment curves were determined at 0.9, 1.1, 1.2, and 1.3 times the NWR threshold intensity. RESULTS: The NWR threshold was significantly higher for the hind limb (median value, 6.6 mA; range, 3 to 10 mA) than the forelimb (median, 3 mA; range, 1.7 to 5.5 mA). The NWR of the hind limb had a significantly longer latency (median, 122.8 milliseconds; range, 106 to 172 milliseconds), compared with the forelimb (median, 98 milliseconds; range, 86 to 137 milliseconds), and it was associated with significantly stronger behavioral reactions. Gradual increase of NWR amplitude was evident at increasing stimulation intensities and supported by the behavioral observations. CONCLUSIONS AND CLINICAL RELEVANCE: We documented NWRs evoked from the forelimb and hind limb and their recruitment with stimuli of increasing intensity in horses. These results provide a basis for use of NWRs in studies on nociceptive modulation in horses. |
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Department of Clinical Veterinary Sciences, University of Berne, Switzerland |
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0002-9645 |
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PMID:12828255 |
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Call Number |
refbase @ user @ |
Serial |
93 |
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Author |
Smith, D.G.; Pearson, R.A. |
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A review of the factors affecting the survival of donkeys in semi-arid regions of sub-Saharan Africa |
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Journal Article |
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Year |
2005 |
Publication |
Tropical Animal Health and Production |
Abbreviated Journal |
Trop Anim Health Prod |
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Volume |
37 Suppl 1 |
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Pages |
1-19 |
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Keywords |
Africa South of the Sahara; Animal Nutrition Physiology; Animals; Behavior, Animal; Cattle; Equidae/growth & development/*physiology; Socioeconomic Factors |
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The large fluctuations seen in cattle populations during periods of drought in sub-Saharan Africa are not evident in the donkey population. Donkeys appear to have a survival advantage over cattle that is increasingly recognized by smallholder farmers in their selection of working animals. The donkey's survival advantages arise from both socioeconomic and biological factors. Socioeconomic factors include the maintenance of a low sustainable population of donkeys owing to their single-purpose role and their low social status. Also, because donkeys are not usually used as a meat animal and can provide a regular income as a working animal, they are not slaughtered in response to drought, as are cattle. Donkeys have a range of physiological and behavioural adaptations that individually provide small survival advantages over cattle but collectively may make a large difference to whether or not they survive drought. Donkeys have lower maintenance costs as a result of their size and spend less energy while foraging for food; lower energy costs result in a lower dry matter intake (DMI) requirement. In donkeys, low-quality diets are digested almost as efficiently as in ruminants and, because of a highly selective feeding strategy, the quality of diet obtained by donkeys in a given pasture is higher than that obtained by cattle. Lower energy costs of walking, longer foraging times per day and ability to tolerate thirst may allow donkeys to access more remote, under-utilized sources of forage that are inaccessible to cattle on rangeland. As donkeys become a more popular choice of working animal for farmers, specific management practices need to be devised that allow donkeys to fully maximize their natural survival advantages. |
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Department of Agriculture and Forestry, University of Aberdeen, Aberdeen, AB24 3FX, Scotland, UK. d.g.smith@abdn.ac.uk |
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0049-4747 |
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PMID:16335068 |
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Equine Behaviour @ team @ |
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4231 |
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Author |
Sloet van Oldruitenborgh-Oosterbaan, M.M.; Spierenburg, A.J.; van den Broek, E.T.W. |
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Title |
The workload of riding-school horses during jumping |
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Year |
2006 |
Publication |
Equine Veterinary Journal. Supplement |
Abbreviated Journal |
Equine Vet J Suppl |
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Volume |
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Issue |
36 |
Pages |
93-97 |
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Keywords |
Acid-Base Equilibrium/physiology; Animals; Blood Gas Analysis/veterinary; Blood Glucose/metabolism; Cross-Over Studies; Electrolytes/blood; Female; Heart Rate/*physiology; Hematocrit/veterinary; Horses/blood/*physiology; Lactates/*blood; Male; Physical Conditioning, Animal/*physiology; *Sports; Time Factors; Water-Electrolyte Balance/physiology |
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REASONS FOR PERFORMING THE STUDY: As there are no reports on the real workload of horses that jump fences, this study was undertaken in riding-school horses. OBJECTIVE: To compare the workload of horses jumping a course of fences with that of horses cantering over the same course at the same average speed without jumping fences. The workload variables included heart rate (HR), packed cell volume (PCV), acid-base balance (venous pH, pCO2, HCO3-) and blood lactate (LA), glucose, total protein and electrolyte concentrations. METHODS: Eight healthy riding-school horses performed test A (a course of approximately 700 m with 12 jumps from 0.8-1.0 m high at an average speed of approximately 350 m/min) and test B (same course at the same speed, but without the rails) in a crossover study with at least 4 h between the 2 tests. Before each test the horses were fitted with a heart rate meter (Polar Electro). Blood samples were taken from the jugular vein at rest prior to the test, after warm-up before starting the course, immediately after the course and after recovery. All samples were analysed immediately. RESULTS: The mean +/- s.d maximal HR (beats/min) during the course (184 +/- 17 and 156 +/- 21, respectively) and the mean HR after recovery (75 +/- 6 and 63 +/- 7, respectively) were significantly higher in test A compared to test B (P = 0.001 and P = 0.007 respectively). The mean LA concentrations after the course and after recovery (mmol/l) were significantly higher in test A (3.6 +/- 2.7 and 1.0 +/- 0.9, respectively) compared to test B (0.9 +/- 0.5 and 0.3 +/- 0.1, respectively), (P = 0.016 and P = 0.048 respectively). The mean PCV (I/l) after the course and after recovery was also significantly different between tests A (0.48 +/- 0.04 and 0.39 +/- 0.03, respectively) and B (0.42 +/- 0.04 and 0.36 +/- 0.03, respectively) (P<0.01). The mean pH and the mean HCO3- (mmol/l) after the course were significantly lower in test A (7.40 +/- 0.04 and 28.9 +/- 1.4, respectively) compared to test B (7.45 +/- 0.03 and 30.4 +/- 2.3, respectively) (P<0.05). CONCLUSIONS: This study indicates that in riding-school horses jumping fences, even at a low level competition, provokes a significant workload compared to cantering the same distance and speed without fences. POTENTIAL RELEVANCE: This study makes it clear that the extra workload of jumping fences should be taken into account in the training programmes of jumping horses. Further research with more experienced horses jumping higher fences will reveal the workload for top-level jumping horses. |
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Department of Equine Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 114, 3584 CM Utrecht, The Netherlands |
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PMID:17402399 |
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Call Number |
Equine Behaviour @ team @ |
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3760 |
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Sloet van Oldruitenborgh-Oosterbaan, M.M.; Blok, M.B.; Begeman, L.; Kamphuis, M.C.D.; Lameris, M.C.; Spierenburg, A.J.; Lashley, M.J.J.O. |
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Title |
Workload and stress in horses: comparison in horses ridden deep and round ('rollkur') with a draw rein and horses ridden in a natural frame with only light rein contact |
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Journal Article |
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Year |
2006 |
Publication |
Tijdschrift Voor Diergeneeskunde |
Abbreviated Journal |
Tijdschr Diergeneeskd |
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Volume |
131 |
Issue |
5 |
Pages |
152-157 |
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Animal Husbandry/methods; Animals; Biomechanics; Blood Glucose/analysis; Female; Heart Rate/physiology; Hematocrit/veterinary; Horses/blood/*physiology; Hydrocortisone/blood; Lactic Acid/blood; Physical Conditioning, Animal/adverse effects/*physiology; Stress, Physiological/blood/etiology/veterinary |
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'Rollkur' or 'overbending' is the low and deep riding of a dressage horse during training or warming up. Lately, this technique has been criticized, and not necessarily objectively, on welfare grounds. To be able to evaluate these criticisms, more needs to be known about the workload and stress of horses being ridden 'rollkur'. The aim of the present study was to compare the workload of eight riding-school horses when being ridden deep and round with a draw rein ('rollkur') and when being ridden in a natural frame with only light rein contact ('free'). Workload (as measured by heart rate and blood lactate concentration) was slightly higher when horses were ridden 'rollkur' than when they were ridden 'free'. There were no differences in packed cell volume, or glucose and cortisol concentrations. No signs of uneasiness or stress could be determined when the horses were ridden 'rollkur'. Subjectively, all horses improved their way of moving during 'rollkur' and were more responsive to their rider. |
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Department of Equine Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 12, 3584 CM Utrecht, The Netherlands. m.sloet@vet.uu.nl |
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0040-7453 |
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PMID:16532786 |
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Equine Behaviour @ team @ |
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5638 |
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Skov-Rackette, S.I.; Miller, N.Y.; Shettleworth, S.J. |
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Title |
What-where-when memory in pigeons |
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Journal Article |
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Year |
2006 |
Publication |
Journal of experimental psychology. Animal behavior processes |
Abbreviated Journal |
J Exp Psychol Anim Behav Process |
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32 |
Issue |
4 |
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345-358 |
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Animals; Behavior, Animal/physiology; Columbidae; Conditioning, Operant/physiology; Memory/*physiology; Reinforcement (Psychology); Space Perception/*physiology; Spatial Behavior/physiology; Teaching; Visual Perception/physiology |
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The authors report a novel approach to testing episodic-like memory for single events. Pigeons were trained in separate sessions to match the identity of a sample on a touch screen, to match its location, and to report on the length of the retention interval. When these 3 tasks were mixed randomly within sessions, birds were more than 80% correct on each task. However, performance on 2 different tests in succession after each sample was not consistent with an integrated memory for sample location, time, and identity. Experiment 2 tested binding of location and identity memories in 2 different ways. The results were again consistent with independent feature memories. Implications for tests of episodic-like memory are discussed. |
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Department of Psychology, University of Toronto, Toronto, ON, Canada |
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0097-7403 |
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PMID:17044738 |
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refbase @ user @ |
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357 |
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Skedros, J.G.; Dayton, M.R.; Sybrowsky, C.L.; Bloebaum, R.D.; Bachus, K.N. |
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The influence of collagen fiber orientation and other histocompositional characteristics on the mechanical properties of equine cortical bone |
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Journal Article |
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Year |
2006 |
Publication |
The Journal of Experimental Biology |
Abbreviated Journal |
J Exp Biol |
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Volume |
209 |
Issue |
Pt 15 |
Pages |
3025-3042 |
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Animals; Biomechanics; Bone and Bones/*physiology; Collagen/*physiology; Forelimb; Horses/*physiology |
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This study examined relative influences of predominant collagen fiber orientation (CFO), mineralization (% ash), and other microstructural characteristics on the mechanical properties of equine cortical bone. Using strain-mode-specific (S-M-S) testing (compression testing of bone habitually loaded in compression; tension testing of bone habitually loaded in tension), the relative mechanical importance of CFO and other material characteristics were examined in equine third metacarpals (MC3s). This model was chosen since it had a consistent non-uniform strain distribution estimated by finite element analysis (FEA) near mid-diaphysis of a thoroughbred horse, net tension in the dorsal/lateral cortices and net compression in the palmar/medial cortices. Bone specimens from regions habitually loaded in tension or compression were: (1) tested to failure in both axial compression and tension in order to contrast S-M-S vs non-S-M-S behavior, and (2) analyzed for CFO, % ash, porosity, fractional area of secondary osteonal bone, osteon cross-sectional area, and population densities of secondary osteons and osteocyte lacunae. Multivariate multiple regression analyses revealed that in S-M-S compression testing, CFO most strongly influenced total energy (pre-yield elastic energy plus post-yield plastic energy); in S-M-S tension testing CFO most strongly influenced post-yield energy and total energy. CFO was less important in explaining S-M-S elastic modulus, and yield and ultimate stress. Therefore, in S-M-S loading CFO appears to be important in influencing energy absorption, whereas the other characteristics have a more dominant influence in elastic modulus, pre-yield behavior and strength. These data generally support the hypothesis that differentially affecting S-M-S energy absorption may be an important consequence of regional histocompositional heterogeneity in the equine MC3. Data inconsistent with the hypothesis, including the lack of highly longitudinal collagen in the dorsal-lateral ;tension' region, paradoxical histologic organization in some locations, and lack of significantly improved S-M-S properties in some locations, might reflect the absence of a similar habitual strain distribution in all bones. An alternative strain distribution based on in vivo strain measurements, without FEA, on non-Thoroughbreds showing net compression along the dorsal-palmar axis might be more characteristic of the habitual loading of some of the bones that we examined. In turn, some inconsistencies might also reflect the complex torsion/bending loading regime that the MC3 sustains when the animal undergoes a variety of gaits and activities, which may be representative of only a portion of our animals, again reflecting the possibility that not all of the bones examined had similar habitual loading histories. |
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Utah Bone and Joint Center, 5323 S. Woodrow Street #202, Salt Lake City, UT 84107, USA. jskedros@utahboneandjoint.com |
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English |
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0022-0949 |
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Notes |
PMID:16857886 |
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no |
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Serial |
1868 |
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Author |
Sivak, J.G.; Allen, D.B. |
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Title |
An evaluation of the “ramp” retina of the horse eye |
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Journal Article |
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Year |
1975 |
Publication |
Vision Research |
Abbreviated Journal |
Vision Res |
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Volume |
15 |
Issue |
12 |
Pages |
1353-1356 |
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Keywords |
Accommodation, Ocular; Animals; Aqueous Humor/physiology; Cornea/physiology; Freezing; Horses/*anatomy & histology; Lens, Crystalline/anatomy & histology/physiology; Refraction, Ocular; Retina/*anatomy & histology; Vitreous Body/physiology |
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Abstract |
Using a rapid freezing and sectioning technique, the distance between the lens and retina of the horse eye was measured. There is no indication of a ramp retina that could serve accommodation. The pupil axis of the eye coincides with the maximum lens to retina distance. The changes in the lens-retina distance are greater below the axis than above it. Calculations were made of refractive power of the horse eye from measurements of curvature and refractive indices of the ocular tissues. These calculations agree both qualitatively and quantitatively with retinoscopic measurements on live horses. Both show that the refractive state shifts in the direction of hyperopia above and below the axis and that this shift is greater below the axis than above it. Some dynamic accommodative ability in the living eye was observed. |
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English |
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ISSN |
0042-6989 |
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Notes |
PMID:1210017 |
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Call Number |
Equine Behaviour @ team @ |
Serial |
3647 |
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