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Author |
Domjan, M. |
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Title |
Selective suppression of drinking during a limited period following aversive drug treatment in rats |
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Journal Article |
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Year |
1977 |
Publication |
Journal of Experimental Psychology. Animal Behavior Processes |
Abbreviated Journal |
J Exp Psychol Anim Behav Process |
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Volume |
3 |
Issue |
1 |
Pages |
66-76 |
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Animals; *Avoidance Learning; Awareness; Conditioning, Operant; Dose-Response Relationship, Drug; Drinking Behavior/*drug effects; Lithium/*poisoning; Male; Osmolar Concentration; Rats; Saccharin/administration & dosage; *Taste; Time Factors |
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Administration of lithium chloride disrupted the intake of flavored solutions but not water in rats. This intake suppression was directly related to the amount of lithium administered (Experiment 1), occurred with both palatable and unpalatable novel saccharin solutions (Experiment 2), but was only observed if subjects were tested starting less than 75 min. after lithium treatment (Experiment 3). Twenty-five daily exposures to saccharin did not attenuate the effect (Experiment 4). However, in saccharin-reared and vinegar-reared rats, lithium did not disrupt consumption of the solutions these subjects had access to throughout life, even though suppressions of intake were observed when these subjects were tested with novel flavors (Experiment 5). The selective disruption of drinking is interpreted as a novelty-dependent sensitization reaction to the discomfort of aversive drug administration. |
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0097-7403 |
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PMID:845544 |
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Equine Behaviour @ team @ |
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2788 |
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Mitchell, D.; Kirschbaum, E.H.; Perry, R.L. |
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Title |
Effects of neophobia and habituation on the poison-induced avoidance of exteroceptive stimuli in the rat |
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Journal Article |
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Year |
1975 |
Publication |
Journal of Experimental Psychology. Animal Behavior Processes |
Abbreviated Journal |
J Exp Psychol Anim Behav Process |
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Volume |
1 |
Issue |
1 |
Pages |
47-55 |
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Animals; Avoidance Learning/*drug effects; *Awareness; *Cognition; Conditioning, Operant; Feeding Behavior/drug effects; *Habituation, Psychophysiologic; Injections, Intraperitoneal; Lithium/administration & dosage/poisoning; Male; Rats; *Taste; Time Factors; *Visual Perception |
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Two experiments on the role of neophobia in poison-induced aversions to exteroceptive stimuli are reported. In Experiment 1, rats were given either 10 or 25 days of habituation to the test situation prior to conditioning. Those animals with the longer habituation period avoided a complex of novel exteroceptive stimuli while those with the shorter habituation period did not. In Experiment 2 rats initially avoided the more novel of two containers, but gradually came to eat equal amounts from both. A single pairing of toxicosis with consumption from either the novel or the familiar container reinstated the avoidance of the novel container in both cases. The results were discussed in terms of an interaction between habituation and conditioning procedures. It was suggested that previously reported differences between interoceptive and exteroceptive conditioning effects may have been influenced by the differential novelty of the two classes of stimuli in the test situation. It was further suggested that non-contingently poisoned control groups should routinely be included in poison avoidance conditioning studies. |
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0097-7403 |
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PMID:1151289 |
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Equine Behaviour @ team @ |
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2791 |
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Author |
Blokland, A. |
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Title |
Reaction time responding in rats |
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Journal Article |
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Year |
1998 |
Publication |
Neuroscience and Biobehavioral Reviews |
Abbreviated Journal |
Neurosci Biobehav Rev |
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22 |
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6 |
Pages |
847-864 |
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Amphetamine/pharmacology; Animals; Behavior, Animal/drug effects/*physiology; Conditioning, Operant/drug effects/*physiology; Dopamine Uptake Inhibitors/pharmacology; Dose-Response Relationship, Drug; Male; Rats; Rats, Inbred Lew; Reaction Time/drug effects/*physiology |
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The use of reaction time has a great tradition in the field of human information processing research. In animal research the use of reaction time test paradigms is mainly limited to two research fields: the role of the striatum in movement initiation; and aging. It was discussed that reaction time responding can be regarded as “single behavior”, this term was used to indicate that only one behavioral category is measured, allowing a better analysis of brain-behavior relationships. Reaction time studies investigating the role of the striatum in motor functions revealed that the initiation of a behavioral response is dependent on the interaction of different neurotransmitters (viz. dopamine, glutamate, GABA). Studies in which lesions were made in different brain structures suggested that motor initiation is dependent on defined brain structures (e.g. medialldorsal striatum, prefrontal cortex). It was concluded that the use of reaction time measures can indeed be a powerful tool in studying brain-behavior relationships. However, there are some methodological constraints with respect to the assessment of reaction time in rats, as was tried to exemplify by the experiments described in the present paper. On the one hand one should try to control for behavioral characteristics of rats that may affect the validity of the parameter reaction time. On the other hand, the mean value of reaction time should be in the range of what has been reported in man. Although these criteria were not always met in several studies, it was concluded that reaction time can be validly assessed in rats. Finally, it was discussed that the use of reaction time may go beyond studies that investigate the role of the basal ganglia in motor output. Since response latency is a direct measure of information processing this parameter may provide insight into basic elements of cognition. Based on the significance of reaction times in human studies the use of this dependent variable in rats may provide a fruitful approach in studying brain-behavior relationships in cognitive functions. |
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Department of Psychology, University of Maastricht, The Netherlands |
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0149-7634 |
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PMID:9809315 |
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Equine Behaviour @ team @ |
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2807 |
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Rizzolatti, G.; Fogassi, L.; Gallese, V. |
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Title |
Mirrors of the mind |
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Journal Article |
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2006 |
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Scientific American |
Abbreviated Journal |
Sci Am |
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295 |
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5 |
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54-61 |
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Animals; Brain/*physiology; Cognition/*physiology; Discrimination (Psychology)/physiology; Emotions/physiology; Humans; Imitative Behavior; Learning/*physiology; Mental Processes/*physiology; Motor Activity/physiology; Neurons/physiology; Recognition (Psychology); Sensation/physiology |
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Neurosciences Department, University of Parma, Italy |
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0036-8733 |
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PMID:17076084 |
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Equine Behaviour @ team @ |
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2829 |
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Author |
Gray, E.R.; Spetch, M.L. |
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Title |
Pigeons Encode Absolute Distance but Relational Direction From Landmarks and Walls |
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Journal Article |
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Year |
2006 |
Publication |
Journal of Experimental Psychology: Animal Behavior Processes |
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32 |
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4 |
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474-480 |
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spatial cognition; absolute distance; relational direction; landmark configurations |
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In recent studies, researchers have examined animals' use of absolute or relational distances in finding a hidden goal. When trained with an array of landmarks, most animals use the default strategy of searching at an absolute distance from 1 or more landmarks. In contrast, when trained in enclosures, animals often use the relationship among walls. In the present study, pigeons were trained to find the center of an array of landmarks or a set of short walls that did not block external cues. Expansion tests showed that both groups of pigeons primarily used an absolute distance strategy. However, on rotational tests, pigeons continued to search in the center of the array, suggesting that direction was learned in relation to array. |
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Equine Behaviour @ team @ |
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2894 |
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Author |
Simpson, B.S. |
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Title |
Neonatal foal handling |
Type |
Journal Article |
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Year |
2002 |
Publication |
Applied Animal Behaviour Science |
Abbreviated Journal |
Appl. Anim. Behav. Sci. |
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78 |
Issue |
2-4 |
Pages |
303-317 |
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Neonatal foal handling; Imprint training; Learning in foals; Heart rate; Serum cortisol concentrations |
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Recent interest has focused on the advantage of intensively handling young foals as a means of producing more tractable horses, accustomed to humans and receptive to training. To date, the effect of this intensive handling, dubbed “imprint training” in the popular literature, has not been tested. The present study compares seven foals handled intensively as neonates with eight untreated controls. The handling protocol started from 2-8 h after birth and continued daily for a total of 5 days. The protocol consisted of a series of stimuli and experiences that were each repeated until the foal no longer resisted or reacted negatively. Subsequently, foals were tested before weaning, at 4 months of age. Results indicated that handled foals (HF) ranked higher than control foals (CF) in subjective ratings of calmness (*P<0.0117) and friendliness (*P<0.0001) and in several specific handling tasks (venipuncture *P<0.0220; placing in stock *P<0.0128). Although, in approach tests all foals but one allowed approach of a person to 4 m, significantly more HF approached the person than CF (P<0.0080). In stimulus tests, foals were presented specific stimuli to which they had been tested as neonates. Two of eight CF were too unruly and dangerous to test. Of foals that could be tested, CF required significantly more time to hook-up a heart rate monitor (**P<0.0055). Split-plot analysis indicated that HF had lower heart rates to initial left-sided stimuli, presented first, than CF (*P<0.0421). In response to right-sided stimuli, heart rate scores of CF were not significantly different from HF (P<0.2259), suggesting reduced reactivity over time due to a learning effect. Behavioral responses to specific stimuli did not differ between CF and HF, suggesting that neonatal handling has a general rather than specific effect on subsequent behavior. Cortisol concentrations were measured before and after testing and the difference calculated. All foals had higher post-testing levels than pre-testing levels. There was a significant difference between HF and CF, indicating greater reactivity among the CF (*P<0.050). In general, the results indicated that foals handled as neonates were more tractable and less reactive. Specific neonatal handling tasks, such as sticking a finger up the foal's nose or patting the bottom of the foot, seemed to have no beneficial effect on related tasks such as passing a nasogastric tube or tapping with a farrier's hammer at 4 months of age. Mechanisms for the observed effect of neonatal handling require further investigation. |
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Equine Behaviour @ team @ |
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3623 |
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Anderson, T.M.; McIlwraith, C.W.; Douay, P. |
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Title |
The role of conformation in musculoskeletal problems in the racing Thoroughbred |
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Journal Article |
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2004 |
Publication |
Equine Veterinary Journal |
Abbreviated Journal |
Equine Vet J |
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36 |
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7 |
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571-575 |
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Animals; Carpus, Animal/anatomy & histology/physiology; Horse Diseases/etiology/*pathology/surgery; Horses/*anatomy & histology/injuries/physiology; Likelihood Functions; Logistic Models; Muscle, Skeletal/*anatomy & histology/pathology; Musculoskeletal Diseases/pathology/surgery/*veterinary; Tarsus, Animal/anatomy & histology/physiology; Treatment Outcome |
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REASONS FOR PERFORMING STUDY: The relationship of conformation to future potential injury is a standard approach in practise but, at present, is largely based on subjective observations. OBJECTIVE: To measure conformation in 3-year-old Thoroughbreds and objectively test its relationship with the occurrence of musculoskeletal problems. METHODS: Conformation measurements were taken from photographs using specific reference points marked on the horses and processed on the computer. Clinical observations were recorded for each horse on a regular basis. Stepwise (forward) logistic regression analysis was performed to investigate the relationship between the binary response of the clinical outcomes probability and the conformation variables by the method of maximum likelihood. RESULTS: Clinical outcomes significantly (P<0.05) associated with conformational variables included effusion of the front fetlock, effusion of the right carpus, effusion of the carpus, effusion of the hind fetlock, fracture of the left or right carpus, right front fetlock problem and hind fetlock problem. CONCLUSIONS: Offset knees (offset ratio) contributed to fetlock problems. Long pasterns increased the odds of a fracture in the front limb. An increase in the carpal angle as viewed from the front (carpal valgus) may serve as a protective mechanism, as the odds for a carpal fracture and carpal effusion decreased with an increase in the carpal angle. POTENTIAL RELEVANCE: This study demonstrates relationships between conformation and musculoskeletal disease in the racehorse. The information may be useful in selection and management of the racing Thoroughbred. |
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Colorado State University, Equine Science and Equine Orthopaedic Research Programs, Fort Collins, Colorado 80523, USA |
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0425-1644 |
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PMID:15581320 |
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Equine Behaviour @ team @ |
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3697 |
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Kristiansen, K.K.; Kold, S.E. |
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Multivariable analysis of factors influencing outcome of 2 treatment protocols in 128 cases of horses responding positively to intra-articular analgesia of the distal interphalangeal joint |
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Journal Article |
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2007 |
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Equine Veterinary Journal |
Abbreviated Journal |
Equine Vet J |
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39 |
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2 |
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150-156 |
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Analgesia/methods/*veterinary; Anesthesia, Local/methods/veterinary; Animals; Anti-Inflammatory Agents/therapeutic use; Female; Foot Diseases/drug therapy/prevention & control/*veterinary; Glycosaminoglycans/therapeutic use; Horse Diseases/*drug therapy/prevention & control; Horses; Injections, Intra-Articular/*veterinary; Joint Diseases/drug therapy/prevention & control/veterinary; Lameness, Animal/drug therapy/prevention & control; Male; Methylprednisolone/analogs & derivatives/therapeutic use; Multivariate Analysis; Pain/prevention & control/veterinary; Retrospective Studies; Time Factors; *Toe Joint/drug effects/pathology; Treatment Outcome |
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REASONS FOR PERFORMING STUDY: There is limited knowledge available of factors influencing response to treatments of the DIP-joint in horses with lameness responding to diagnostic analgesia of the DIP-joint. For this reason a multivariable statistical analysis was performed. HYPOTHESIS: Horses with lameness reduced by > or = 75% 10 min after intra-articular analgesia of the DIP-joint, can be treated successfully by intra-articular medication of the joint. Multiple factors influence the response to treatment. METHODS: The study was performed retrospectively based on clinical records of horses treated with either polysulphated glycosaminoglycan (PSGAG) or methylprednisolone acetate (MPA) in the DIP-joint between January 1996 and January 2003. Information was collected from clinical records and from the owners of the horses via a detailed questionnaire, in which they described their perception of the outcome a minimum of one year after treatment. Allocation of the horses to the 2 treatment groups was done mainly because of a change in treatment policy. In Regime A all horses received 3 intra-articular injections of PSGAG approximately 8 days apart, whereas in Regime B all horses received a single intra-articular injection of MPA as a first treatment. If the horse did not improve sufficiently to return to work by 4 weeks, a series of 3 intra-articular PSGAG injections was administered. RESULTS: Of the horses receiving Regime A, 67% had a successful outcome, compared with 46% of the group receiving Regime B. A significantly better result was obtained in dressage horses than in jumping horses (eventing and showjumping). Other variables such as age, duration of lameness, distribution of lameness, degree of lameness, response to DIP-joint analgesia and radiographic observations were also associated with success of treatment. CONCLUSIONS AND POTENTIAL RELEVANCE: There is a rationale for using either PSGAG or MPA intra-articularly in the treatment of lameness, reduced > or = 75% within 10 min of analgesia of the DIP-joint. |
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Willesley Equine Clinic Ltd., Tetbury, Gloucestershire, GL8 8QU UK |
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PMID:17378444 |
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Equine Behaviour @ team @ |
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3707 |
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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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2003 |
Publication |
American Journal of Veterinary Research |
Abbreviated Journal |
Am J Vet Res |
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64 |
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3 |
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338-345 |
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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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Gulotta, M.; Rogatsky, E.; Callender, R.H.; Dyer, R.B. |
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Primary folding dynamics of sperm whale apomyoglobin: core formation |
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Journal Article |
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Year |
2003 |
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Biophysical Journal |
Abbreviated Journal |
Biophys J |
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84 |
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3 |
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1909-1918 |
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Animals; Apoproteins/*chemistry; Crystallography/*methods; Horses; Myocardium/chemistry; Myoglobin/*chemistry; Protein Conformation; *Protein Folding; Species Specificity; Structure-Activity Relationship; Temperature; Whales |
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The structure, thermodynamics, and kinetics of heat-induced unfolding of sperm whale apomyoglobin core formation have been studied. The most rudimentary core is formed at pH(*) 3.0 and up to 60 mM NaCl. Steady state for ultraviolet circular dichroism and fluorescence melting studies indicate that the core in this acid-destabilized state consists of a heterogeneous composition of structures of approximately 26 residues, two-thirds of the number involved for horse heart apomyoglobin under these conditions. Fluorescence temperature-jump relaxation studies show that there is only one process involved in Trp burial. This occurs in 20 micro s for a 7 degrees jump to 52 degrees C, which is close to the limits placed by diffusion on folding reactions. However, infrared temperature jump studies monitoring native helix burial are biexponential with times of 5 micro s and 56 micro s for a similar temperature jump. Both fluorescence and infrared fast phases are energetically favorable but the slow infrared absorbance phase is highly temperature-dependent, indicating a substantial enthalpic barrier for this process. The kinetics are best understood by a multiple-pathway kinetics model. The rapid phases likely represent direct burial of one or both of the Trp residues and parts of the G- and H-helices. We attribute the slow phase to burial and subsequent rearrangement of a misformed core or to a collapse having a high energy barrier wherein both Trps are solvent-exposed. |
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Department of Biochemistry, Albert Einstein College of Medicine, Bronx, New York 10461, USA. gulotta@aecom.yu.edu |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0006-3495 |
ISBN |
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Expedition |
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Conference |
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Notes |
PMID:12609893 |
Approved |
no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
3783 |
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