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Author (up) Cameron, E.Z.; du Toit, J.T.
Title Winning by a neck: tall giraffes avoid competing with shorter browsers Type Journal Article
Year 2007 Publication The American naturalist Abbreviated Journal Am Nat
Volume 169 Issue 1 Pages 130-135
Keywords Acacia/growth & development; Animals; Feeding Behavior/*physiology; Neck/*anatomy & histology; Plant Leaves/growth & development; Ruminants/*anatomy & histology/*physiology; South Africa
Abstract With their vertically elongated body form, giraffes generally feed above the level of other browsers within the savanna browsing guild, despite having access to foliage at lower levels. They ingest more leaf mass per bite when foraging high in the tree, perhaps because smaller, more selective browsers deplete shoots at lower levels or because trees differentially allocate resources to promote shoot growth in the upper canopy. We erected exclosures around individual Acacia nigrescens trees in the greater Kruger ecosystem, South Africa. After a complete growing season, we found no differences in leaf biomass per shoot across height zones in excluded trees but significant differences in control trees. We conclude that giraffes preferentially browse at high levels in the canopy to avoid competition with smaller browsers. Our findings are analogous with those from studies of grazing guilds and demonstrate that resource partitioning can be driven by competition when smaller foragers displace larger foragers from shared resources. This provides the first experimental support for the classic evolutionary hypothesis that vertical elongation of the giraffe body is an outcome of competition within the browsing ungulate guild.
Address Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria 0002, South Africa. ezcameron@zoology.up.ac.za
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1537-5323 ISBN Medium
Area Expedition Conference
Notes PMID:17206591 Approved no
Call Number refbase @ user @ Serial 410
Permanent link to this record
 
 
Author (up) Cancedda, M.
Title [Social and behavioral organization of horses on the Giara (Sardinia): distribution and aggregation] Type Journal Article
Year 1990 Publication Bollettino della Societa italiana di biologia sperimentale Abbreviated Journal Boll Soc Ital Biol Sper
Volume 66 Issue 11 Pages 1089-1096
Keywords Animals; *Animals, Wild/physiology/psychology; Environment; Female; *Horses/physiology/psychology; Italy; Male; Population Density; Sexual Behavior, Animal; *Social Behavior; Social Dominance; Water
Abstract In this paper some considerations on the environment of the 42 Kmq of the volcanic-basaltic Giara tableland are discussed. Conditioning by the environment and its effect on the distribution of a population of 712 horses is illustrated in view of their social and behavioural organization.
Address Istituto di Fisiologia Generale e Speciale, Universita di Sassari
Corporate Author Thesis
Publisher Place of Publication Editor
Language Italian Summary Language Original Title Introduzione all'organizzazione sociale e comportamentale dei cavallini sulla Giara (Sardegna): distribuzione ed aggregazione
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0037-8771 ISBN Medium
Area Expedition Conference
Notes PMID:2095819 Approved no
Call Number refbase @ user @ Serial 673
Permanent link to this record
 
 
Author (up) Capela, R.; Sousa, C.; Pena, I.; Caeiro, V.
Title Preliminary note on the distribution and ecology of Culicoides imicola in Portugal Type Journal Article
Year 1993 Publication Medical and Veterinary Entomology Abbreviated Journal Med Vet Entomol
Volume 7 Issue 1 Pages 23-26
Keywords Animals; *Ceratopogonidae; Ecology; Population Density; Portugal
Abstract Data on Culicoides imicola were obtained during studies carried out during the recent outbreak of African horse sickness in Portugal. The previous most northerly published record of C. imicola in Portugal was 38 degrees 40'N (Pegoes). In the present work the geographical distribution of this species is extended to the parallel of 41 degrees 17'N. We have also confirmed the continuous presence of adult C. imicola in Southern Portugal (Alentejo and Algarve) throughout the year. In the laboratory we obtained this species from a sample of cattle faeces and from another of soil contaminated with animal excreta. In relation to host association 57.37% of C. imicola were trapped in the vicinity of pigsties. Finally, we collected 11,463 Culicoides of which 12.47% were C. imicola.
Address Departamento de Zoologia e Antropologia, Universidade de Lisboa, Portugal
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0269-283X ISBN Medium
Area Expedition Conference
Notes PMID:8435485 Approved no
Call Number Equine Behaviour @ team @ Serial 2666
Permanent link to this record
 
 
Author (up) Capitanio, J.P.
Title Personality dimensions in adult male rhesus macaques: prediction of behaviors across time and situation Type Journal Article
Year 1999 Publication American journal of primatology Abbreviated Journal Am. J. Primatol.
Volume 47 Issue 4 Pages 299-320
Keywords Animals; *Behavior, Animal; Forecasting; Macaca mulatta/*psychology; Male; *Personality; Psychometrics; Social Behavior
Abstract The idea that consistencies in behavior exist over time and across situations underlies human personality research. Although several studies have examined personality in nonhuman primates, there are very few data showing the predictive power of personality factors. The goal of the present study was to determine whether personality dimensions, identified in adult male rhesus monkeys living in half-acre cages, predicted behavior in situations different from the one from which the dimensions were originally derived and at time points of up to 4.5 years after the original assessments. Four personality dimensions (Sociability, Confidence, Excitability, and Equability) were identified using psychometric procedures and were correlated with behaviors recorded in several situations: the animals' natal groups, during tests of behavioral responsiveness while in individual cages, in small stable and unstable social groups, while viewing stimulus videotapes, and during stable social dyads. Results indicated substantial predictability. Sociability reflected a greater tendency to engage in affiliative interactions. Confidence correlated with more aggressive behaviors and with behaviors that suggest less attractiveness. Animals high in Excitability were somewhat inconsistent in their social behavior, perhaps reflecting hyper-responsiveness to novel circumstances and thwarted opportunities for escape. Equability appeared to be related to a less aggressive, more passive, style of interaction. Excitability and Equability appear to reflect more stylistic components of social behavior, whereas Sociability and Confidence may be more content-based dimensions. Sociability was strongly related to size of kin network in the animals' natal groups, suggesting an important role for ontogeny in this dimension. These data suggest that a limited number of personality dimensions exist in adult male rhesus macaques, and that these dimensions have predictive power that is both long-term and cross situational.
Address Department of Psychology and California Regional Primate Research Center, University of California, Davis 95616, USA. jpcapitanio@ucdavis.edu
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0275-2565 ISBN Medium
Area Expedition Conference
Notes PMID:10206208 Approved no
Call Number Equine Behaviour @ team @ Serial 4116
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Author (up) Capitanio, J.P.; Widaman, K.F.
Title Confirmatory factor analysis of personality structure in adult male rhesus monkeys (Macaca mulatta) Type Journal Article
Year 2005 Publication American journal of primatology Abbreviated Journal Am. J. Primatol.
Volume 65 Issue 3 Pages 289-294
Keywords Animals; *Behavior, Animal; Macaca mulatta/*psychology; Male; *Personality; Psychometrics; Social Behavior
Abstract Reports from different laboratories have suggested that nonhuman primates have somewhat similar dimensions of personality. To date, however, no attempts have been made to statistically replicate a specific factor structure. In the present report, two independent observers recorded the behavior of 58 adult male rhesus monkeys, and then rated the animals with the use of a 50-item personality instrument. A confirmatory factor analysis (CFA) of the ratings resulted in the replication of a previously described four-factor personality structure [Maninger et al., American Journal of Primatology 61:73-83, 2003]. The first two dimensions-Sociability and Confidence-showed strong loadings and are similar to Affiliation and Agency dimensions in humans. The remaining dimensions-Equability and Irritability-were less clear, and it is possible that additional traits will have to be identified before a more robust structure can be established for these dimensions.
Address Department of Psychology, University of California-Davis, Davis, California 95616, USA. jpcapitanio@ucdavis.edu
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0275-2565 ISBN Medium
Area Expedition Conference
Notes PMID:15772988 Approved no
Call Number Equine Behaviour @ team @ Serial 4111
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Author (up) Carmalt, J.L.; Carmalt, K.P.; Barber, S.M.
Title The effect of occlusal equilibration on sport horse performance Type Journal Article
Year 2006 Publication Journal of Veterinary Dentistry Abbreviated Journal J Vet Dent
Volume 23 Issue 4 Pages 226-230
Keywords Analysis of Variance; Animals; Cross-Over Studies; *Dental Occlusion, Balanced; Horse Diseases/*therapy; Horses; Malocclusion/therapy/*veterinary; Occlusal Adjustment/methods/*veterinary; Prospective Studies; Treatment Outcome
Abstract The objective of this study was to investigate the effect of routine dental occlusal equilibration treatment on dressage horse performance. Sixteen horses (11 treated; 5 untreated) ridden by a single rider performed a standardized dressage test twice and were scored by two experienced dressage judges according to recognized movements and rider cues. All horses were sedated and a full-mouth speculum was used to facilitate a complete oral examination. Treated horses had dental equilibration performed using a motorized dental instrument. The horses performed a second test 48-hours after dental equilibration, exactly as the baseline test, with the judges and rider blinded as to treatment group. The total test score as well as the individual movement scores were evaluated for equality of variance and statistical tests were applied to determine the influence of treatment. There was no significant improvement in the test score of horses that had received occlusal equilibration.
Address Scone Veterinary Hospital, NSW, Australia. carmalt_vet@hotmail.com
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0898-7564 ISBN Medium
Area Expedition Conference
Notes PMID:17286128 Approved no
Call Number Equine Behaviour @ team @ Serial 3708
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Author (up) Carroll, C.L.; Huntington, P.J.
Title Body condition scoring and weight estimation of horses Type Journal Article
Year 1988 Publication Equine veterinary journal Abbreviated Journal Equine Vet J
Volume 20 Issue 1 Pages 41-45
Keywords Animals; Biometry; *Body Weight; Female; Horses/*anatomy & histology; Male; Physical Examination/*veterinary
Abstract Three hundred and seventy two horses of varying breeds, height and fatness were weighed and measured for height at the withers. They were assessed for condition score by adaptation of a previously published method. The heart girth and length of 281 of the horses were also measured. Weight of horses was highly correlated (P less than 0.001) with height (r2 = 0.62), condition score (r2 = 0.22) and girth2 x length (r2 = 0.90). Nomograms were constructed to predict weight from height and condition score, and girth and length measurements. Weight can also be accurately estimated from the formula: (formula, see text) The average value of 'Y' in this experiment was 11900 and this estimated weight with more accuracy than some previously published values of 'Y'. Racing Thoroughbred horses were found to be significantly lighter than non-racing Thoroughbreds of the same height and condition score. The method of assessment of condition score was shown to be repeatable between different operators with varying degrees of experience.
Address Department of Agriculture and Rural Affairs, Attwood Veterinary Research Laboratory, Westmeadows, Victoria, Australia
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0425-1644 ISBN Medium
Area Expedition Conference
Notes PMID:3366105 Approved no
Call Number Serial 1808
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Author (up) Carroll, G.L.; Matthews, N.S.; Hartsfield, S.M.; Slater, M.R.; Champney, T.H.; Erickson, S.W.
Title The effect of detomidine and its antagonism with tolazoline on stress-related hormones, metabolites, physiologic responses, and behavior in awake ponies Type Journal Article
Year 1997 Publication Veterinary surgery : VS : the official journal of the American College of Veterinary Surgeons Abbreviated Journal Vet Surg
Volume 26 Issue 1 Pages 69-77
Keywords Adrenergic alpha-Antagonists/administration & dosage/*pharmacology; Animals; Behavior, Animal/drug effects/physiology; Blood Glucose/metabolism; Blood Pressure/drug effects/physiology; Consciousness/physiology; Dose-Response Relationship, Drug; Drug Interactions; Epinephrine/blood; Fatty Acids, Nonesterified/blood; Female; Heart Rate/drug effects/physiology; Horse Diseases/metabolism/physiopathology/psychology; Horses/blood/metabolism/*physiology; Hydrocortisone/blood; Hypnotics and Sedatives/administration & dosage/*pharmacology; Imidazoles/administration & dosage/*pharmacology; Injections, Intravenous; Male; Norepinephrine/blood; Receptors, Adrenergic, alpha/drug effects/*physiology; Stress/metabolism/physiopathology/veterinary; Time Factors; Tolazoline/administration & dosage/*pharmacology
Abstract Six ponies were used to investigate the effect of tolazoline antagonism of detomidine on physiological responses, behavior, epinephrine, norepinephrine, cortisol, glucose, and free fatty acids in awake ponies. Each pony had a catheter inserted into a jugular vein 1 hour before beginning the study. Awake ponies were administered detomidine (0.04 mg/kg intravenously [i.v.]) followed 20 minutes later by either tolazoline (4.0 mg/kg i.v.) or saline. Blood samples were drawn from the catheter 5 minutes before detomidine administration (baseline), 5 minutes after detomidine administration, 20 minutes before detomidine administration which was immediately before the administration of tolazoline or saline (time [T] = 0), and at 5, 30, and 60 minutes after injections of tolazoline or saline (T = 5, 30, and 60 minutes, respectively). Compared with heart rate at T = 0, tolazoline antagonism increased heart rate 45% at 5 minutes. There was no difference in heart rate between treatments at 30 minutes. Blood pressure remained stable after tolazoline, while it decreased over time after saline. Compared with concentrations at T = 0, tolazoline antagonism of detomidine in awake ponies resulted in a 55% increase in cortisol at 30 minutes and a 52% increase in glucose at 5 minutes. The change in free fatty acids was different for tolazoline and saline over time. Free fatty acids decreased after detomidine administration. Free fatty acids did not change after saline administration. After tolazoline administration, free fatty acids increased transiently. Tolazoline tended to decrease sedation and analgesia at 15 and 60 minutes postantagonism. Antagonism of detomidine-induced physiological and behavioral effects with tolazoline in awake ponies that were not experiencing pain appears to precipitate a stress response as measured by cortisol, glucose, and free fatty acids. If antagonism of an alpha-agonist is contemplated, the potential effect on hormones and metabolites should be considered.
Address Department of Small Animal Medicine and Surgery, Texas A&M University, College Station, USA
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0161-3499 ISBN Medium
Area Expedition Conference
Notes PMID:9123816 Approved no
Call Number refbase @ user @ Serial 96
Permanent link to this record
 
 
Author (up) Carroll, J.; Murphy, C.J.; Neitz, M.; Hoeve, J.N.; Neitz, J.
Title Photopigment basis for dichromatic color vision in the horse Type Journal Article
Year 2001 Publication Journal of Vision Abbreviated Journal J Vis
Volume 1 Issue 2 Pages 80-87
Keywords Adaptation, Physiological; Animals; Color Perception/*physiology; Cones (Retina)/chemistry/*physiology; Electroretinography; Horses/*physiology; Photic Stimulation; Phototransduction/physiology; Retinal Pigments/analysis/*physiology; Visual Perception/physiology
Abstract Horses, like other ungulates, are active in the day, at dusk, dawn, and night; and, they have eyes designed to have both high sensitivity for vision in dim light and good visual acuity under higher light levels (Walls, 1942). Typically, daytime activity is associated with the presence of multiple cone classes and color-vision capacity (Jacobs, 1993). Previous studies in other ungulates, such as pigs, goats, cows, sheep and deer, have shown that they have two spectrally different cone types, and hence, at least the photopigment basis for dichromatic color vision (Neitz & Jacobs, 1989; Jacobs, Deegan II, Neitz, Murphy, Miller, & Marchinton, 1994; Jacobs, Deegan II, & Neitz, 1998). Here, electroretinogram flicker photometry was used to measure the spectral sensitivities of the cones in the domestic horse (Equus caballus). Two distinct spectral mechanisms were identified and are consistent with the presence of a short-wavelength-sensitive (S) and a middle-to-long-wavelength-sensitive (M/L) cone. The spectral sensitivity of the S cone was estimated to have a peak of 428 nm, while the M/L cone had a peak of 539 nm. These two cone types would provide the basis for dichromatic color vision consistent with recent results from behavioral testing of horses (Macuda & Timney, 1999; Macuda & Timney, 2000; Timney & Macuda, 2001). The spectral peak of the M/L cone photopigment measured here, in vivo, is similar to that obtained when the gene was sequenced, cloned, and expressed in vitro (Yokoyama & Radlwimmer, 1999). Of the ungulates that have been studied to date, all have the photopigment basis for dichromatic color vision; however, they differ considerably from one another in the spectral tuning of their cone pigments. These differences may represent adaptations to the different visual requirements of different species.
Address Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee, WI, USA
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1534-7362 ISBN Medium
Area Expedition Conference
Notes PMID:12678603 Approved no
Call Number Equine Behaviour @ team @ Serial 4060
Permanent link to this record
 
 
Author (up) Cassiat, G.; Pourcelot, P.; Tavernier, L.; Geiger, D.; Denoix, J.M.; Degueurce, D.
Title Influence of individual competition level on back kinematics of horses jumping a vertical fence Type Journal Article
Year 2004 Publication Equine Veterinary Journal Abbreviated Journal Equine Vet J
Volume 36 Issue 8 Pages 748-753
Keywords 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
Abstract 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.
Address UMR INRA-ENVA de Biomecanique et Pathologie Locomotrice du Cheval, Ecole Nationale Veterinaire d'Alfort, Avenue du General de Gaulle, 94704 Maisons Alfort, France
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0425-1644 ISBN Medium
Area Expedition Conference
Notes PMID:15656509 Approved no
Call Number Equine Behaviour @ team @ Serial 4042
Permanent link to this record