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Pearce, G. P., May-Davis, S., & Greaves, D. (2005). Femoral asymmetry in the Thoroughbred racehorse. Aust Vet J, 83(6), 367–370.
Abstract: OBJECTIVE: To investigate the occurrence of geometrical asymmetries in the macro-architecture of left and right femurs from Thoroughbred racehorses previously used in competitive training and racing in New South Wales, Australia. METHODS: Detailed postmortem measurements were made of 37 characteristics of left and right femurs from eleven Thoroughbred racehorses euthanased for reasons unrelated to the study. Measurements focused on articulating surfaces and sites of attachment of muscles and ligaments known to be associated with hindlimb locomotion. RESULTS: Five measurements were significantly larger in left compared to right femurs (P < 0.05). The regions showing significant differences between left and right limbs were proximal cranial and overhead medio-lateral widths, greater trochanter depth, depth of the fovea in the femoral head and distal inter-epicondylar width. CONCLUSION: The left-right differences in femoral morphology were associated with sites of muscle and ligament attachment known to be involved with hindlimb function in negotiating turns. These differences may be the result of selection pressure for racing performance on curved race tracks and/or adaptations related to asymmetrical loading of the outside hindlimb associated with repeated negotiation of turns on such tracks.
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Santamaria, S., Bobbert, M. F., Back, W., Barneveld, A., & van Weeren, P. R. (2005). Effect of early training on the jumping technique of horses. Am J Vet Res, 66(3), 418–424.
Abstract: OBJECTIVE: To investigate the effects of early training for jumping by comparing the jumping technique of horses that had received early training with that of horses raised conventionally. ANIMALS: 40 Dutch Warmblood horses. PROCEDURE: The horses were analyzed kinematically during free jumping at 6 months of age. Subsequently, they were allocated into a control group that was raised conventionally and an experimental group that received 30 months of early training starting at 6 months of age. At 4 years of age, after a period of rest in pasture and a short period of training with a rider, both groups were analyzed kinematically during free jumping. Subsequently, both groups started a 1-year intensive training for jumping, and at 5 years of age, they were again analyzed kinematically during free jumping. In addition, the horses competed in a puissance competition to test maximal performance. RESULTS: Whereas there were no differences in jumping technique between experimental and control horses at 6 months of age, at 4 years, the experimental horses jumped in a more effective manner than the control horses; they raised their center of gravity less yet cleared more fences successfully than the control horses. However, at 5 years of age, these differences were not detected. Furthermore, the experimental horses did not perform better than the control horses in the puissance competition. CONCLUSIONS AND CLINICAL RELEVANCE: Specific training for jumping of horses at an early age is unnecessary because the effects on jumping technique and jumping capacity are not permanent.
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Fruehwirth, B., Peham, C., Scheidl, M., & Schobesberger, H. (2004). Evaluation of pressure distribution under an English saddle at walk, trot and canter. Equine Vet J, 36(8), 754–757.
Abstract: REASONS FOR PERFORMING STUDY: Basic information about the influence of a rider on the equine back is currently lacking. HYPOTHESIS: That pressure distribution under a saddle is different between the walk, trot and canter. METHODS: Twelve horses without clinical signs of back pain were ridden. At least 6 motion cycles at walk, trot and canter were measured kinematically. Using a saddle pad, the pressure distribution was recorded. The maximum overall force (MOF) and centre of pressure (COP) were calculated. The range of back movement was determined from a marker placed on the withers. RESULTS: MOF and COP showed a consistent time pattern in each gait. MOF was 12.1 +/- 1.2 and 243 +/- 4.6 N/kg at walk and trot, respectively, in the ridden horse. In the unridden horse MOF was 172.7 +/- 11.8 N (walk) and 302.4 +/- 33.9 N (trot). At ridden canter, MOF was 27.2 +/- 4.4 N/kg. The range of motion of the back of the ridden horse was significantly lower compared to the unridden, saddled horse. CONCLUSIONS AND POTENTIAL RELEVANCE: Analyses may help quantitative and objective evaluation of the interaction between rider and horse as mediated through the saddle. The information presented is therefore of importance to riders, saddlers and equine clinicians. With the technique used in this study, style, skill and training level of different riders can be quantified, which would give the opportunity to detect potentially harmful influences and create opportunities for improvement.
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Cassiat, G., Pourcelot, P., Tavernier, L., Geiger, D., Denoix, J. M., & Degueurce, D. (2004). Influence of individual competition level on back kinematics of horses jumping a vertical fence. Equine Vet J, 36(8), 748–753.
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.
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Robert, C., Audigie, F., Valette, J. P., Pourcelot, P., & Denoix, J. M. (2001). Effects of treadmill speed on the mechanics of the back in the trotting saddlehorse. Equine Vet J Suppl, (33), 154–159.
Abstract: Speed related changes in trunk mechanics have not yet been investigated, although high-speed training is currently used in the horse. To evaluate the effects of speed on back kinematics and trunk muscles activity, 4 saddle horses were recorded while trotting on a horizontal treadmill at speeds ranging from 3.5 to 6 m/s. The 3-dimensional (3-D) trajectories of skin markers on the left side of the horse and the dorsal midline of the trunk were established. Electrical activity was simultaneously obtained from the longissimus dorsi (LD) and rectus abdominis (RA) muscles using surface electrodes. Ten consecutive strides were analysed for each horse at each of the 5 velocity steps. Electromyographic and kinematic data were time-standardised to the duration of the stride cycle and compared using an analysis of variance. The back extended during the first part of each diagonal stance phase when the RA was active and the back flexed during the second part of each diagonal stance phase when the LD was active. The onset and end of muscle activity came earlier in the stride cycle and muscle activity intensity increased when speed increased. The amplitude of vertical movement of the trunk and the maximal angles of flexion decreased with increasing speed, whereas the extension angles remained unchanged. This resulted in a decreased range of back flexion-extension. This study confirms that the primary role of trunk muscles is to control the stiffness of the back rather than to induce movements. Understanding the effects of speed on the back of healthy horses is a prerequisite for the prevention and treatment of back pathology.
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Wolfe, J. M. (1983). Hidden visual processes. Sci Am, 248(2), 94–103.
Abstract: Isoluminant stimulus is an image whose edges are defined only by a change in color, not by change in brightness. The stimulus here is imperfect: the blue parts and the green parts of the image are only as nearly equal in brightness as they can be on the printed page. Moreover, the change in brightness beyond the edge of the page is apparent, and so is the fact that the reader is holding the magazine at reading distance. When such cues are removed under laboratory conditions, subjects faced with an isoluminant stimulus prove unable to bring its edges into focus. This deficiency contributes to making a familiar face hard to recognize. The experiment indicates that the brain process underlying visual accommodation (the focusing of the eyes) cannot “see” color; it is a hidden process distinct from the processes that lead to perception. The image shows Groucho Marx as he appeared in the motion picture Horse Feathers.
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Cattell, R. B., & Korth, B. (1973). The isolation of temperament dimensions in dogs. Behav Biol, 9(1), 15–30.
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Meyer, W., & Pakur, M. (1999). [Remarks on the domestic dog as an object of instruction for the education of the developing child]. Berl Munch Tierarztl Wochenschr, 112(4), 131–138.
Abstract: Based on an intensive analysis of literature, the study summarizes problems involved in the significance of domesticated dogs as objects of instruction and assistants of the education of children. Several important topics are discussed in view of advances for children in families keeping dogs. Such topics are mainly related to a general socio-emotional level, the support of cognitive development and character formation. Further aspects are the acquisition of a sense of responsibility, and the development of self-confidence, a sense of social membership and security, as well as important attributes of character such as frankness, broad mindedness, and sympathetic understanding. Moreover, knowledge about the life cycle and functions of body organs can be conveyed, and the dog could, at least in part, substitute for brothers and sisters. Basically, positive attitudes towards animals in general, as well as nature and environment are supported. All topics are critically commented and considered to be realistic or not. The supporting role of parents, in particular, is emphasized. Parental commitment should include deep concern with the typical attributes of the dog breed desired, and optimal dog keeping conditions to prevent harm to the children. The final commentary lays special emphasis on negative features of domestication for a pet owner, and cautions against non-biological and illusionary ideas about domesticated animals.
Keywords: Animals; Animals, Domestic; *Bonding, Human-Pet; Character; Child; *Child Development; Child, Preschool; Cognition; *Dogs; Emotions; Empathy; Humans
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Newberry, R. C., & Swanson, J. C. (2008). Implications of breaking mother-young social bonds. Appl. Anim. Behav. Sci., 110(1-2), 3–23.
Abstract: Whereas mammalian mothers and young may retain long-term social affiliations in nature, the management of animals in captivity typically dictates that offspring are abruptly and permanently separated from their mothers at a relatively early age, often prior to the time of natural weaning. For animal breeders, this strategy can enhance the yield of offspring from a breeding population. Morbidity and mortality can also precipitate severance of mother-young bonds. Although it is recognized that early weaning provides nutritional challenges for the young, relatively little attention has been paid to the psychological consequences and long-term impacts of breaking the mother-young bond in non-human mammals. Furthermore, whereas great strides are being made in our understanding of the neurobiological and genetic underpinnings of social bonding, the mechanisms underlying the process of detachment following establishment of a mother-young bond remain relatively unexplored, although parallels can be drawn with processes involved in withdrawal from addictive substances. In this review, we outline mechanisms involved in social bonding. We consider the diversity in extent and duration of mother-young attachment across mammalian lineages and implications for predicting the outcome of severing ties between mothers and young at different times post-partum. We identify characteristics signalling emotional distress resulting from separation of mothers and young and discuss strategies for mitigating separation-induced distress. These include postponement of separation, ensuring high-quality maternal care of young prior to separation, providing bonded individuals with opportunities to separate voluntarily for brief periods prior to permanent separation, use of anti-suck devices prior to separation, allowing a period of partial (fence line) contact prior to full separation, providing substitutes for stimuli previously exchanged between mother and young, providing social buffers, gradual introduction to new housing arrangements, and pharmacological intervention. Areas for future research are proposed, including the use of functional neuroimaging technologies and functional genomics approaches, in combination with behavioural assessments of reinstatement motivation, individual recognition memory and long-term consequences of early separation, to shed further light on the nature of mother-young bonding and detachment in animals.
Keywords: Animal welfare; Emotion; Separation; Social attachment; Weaning
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Pell, M. D. (2006). Cerebral mechanisms for understanding emotional prosody in speech. Brain and Language, 96(2), 221–234.
Abstract: Hemispheric contributions to the processing of emotional speech prosody were investigated by comparing adults with a focal lesion involving the right (n = 9) or left (n = 11) hemisphere and adults without brain damage (n = 12). Participants listened to semantically anomalous utterances in three conditions (discrimination, identification, and rating) which assessed their recognition of five prosodic emotions under the influence of different task- and response-selection demands. Findings revealed that right- and left-hemispheric lesions were associated with impaired comprehension of prosody, although possibly for distinct reasons: right-hemisphere compromise produced a more pervasive insensitivity to emotive features of prosodic stimuli, whereas left-hemisphere damage yielded greater difficulties interpreting prosodic representations as a code embedded with language content.
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