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Harcourt, J. L., Biau, S., Johnstone, R., & Manica, A. (2010). Boldness and Information Use in Three-Spined Sticklebacks. Ethology, 116(5), 440–447.
Abstract: Abstract In foraging groups, individuals may utilise information from their social environment to aid decision making when choosing where to search for food. Little work has looked at the costs or benefits of behavioural differences, such as consistent individual variation in boldness, with respect to learning ability. Here, we investigate the response of three-spined stickleback (Gasterosteus aculeatus) to ‘social cues’, ‘local enhancement’ and ‘public information’ during foraging tasks. Our results confirm previous work suggesting that this species responds to social cues and local enhancement but not public information. Variation in boldness did not affect the use of different types of information. However, time taken to make a choice and reach a patch varied between fish with different levels of boldness. Contrary to expectation, shy fish were the more variable individuals, having a greater range of reaction times when responding to the tasks. This suggests that individual behavioural differences still play a role when utilising information obtained from the environment and may influence the relative benefits that could result in different contexts.
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Schmidt, A., Biau, S., Möstl, E., Becker-Birck, M., Morillon, B., Aurich, J., et al. (2010). Changes in cortisol release and heart rate variability in sport horses during long-distance road transport. Domest Anim Endocrinol, 38(3), 179–189.
Abstract: It is widely accepted that transport is stressful for horses, but only a few studies are available involving horses that are transported regularly and are accustomed to transport. We determined salivary cortisol immunoreactivity (IR), fecal cortisol metabolites, beat-to-beat (RR) interval, and heart rate variability (HRV) in transport-experienced horses (N = 7) in response to a 2-d outbound road transport over 1370 km and 2-d return transport 8 d later. Salivary cortisol IR was low until 60 min before transport but had increased (P < 0.05) 30 min before loading. Transport caused a further marked increase (P < 0.001), but the response tended to decrease with each day of transport. Concentrations of fecal cortisol metabolites increased on the second day of both outbound and return transports and reached a maximum the following day (P < 0.001). During the first 90 min on Day 1 of outbound transport, mean RR interval decreased (P < 0.001). Standard deviations of RR interval (SDRR) decreased transiently (P < 0.01). The root mean square of successive RR differences (RMSSD) decreased at the beginning of the outbound and return transports (P < 0.01), reflecting reduced parasympathetic tone. On the first day of both outbound and return transports, a transient rise in geometric HRV variable standard deviation 2 (SD2) occurred (P < 0.01), indicating increased sympathetic activity. In conclusion, transport of experienced horses leads to increased cortisol release and changes in heart rate and HRV, which is indicative of stress. The degree of these changes tended to be most pronounced on the first day of both outbound and return transport.
Keywords: Horse; Transport; Cortisol; Heart rate variability
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Barrey, E., Desliens, F., Poirel, D., Biau, S., Lemaire, S., Rivero, J. L. L., et al. (2002). Early evaluation of dressage ability in different breeds. Equine Vet J Suppl, (34), 319–324.
Abstract: Dressage is one of the Olympic equestrian sports practiced in several countries using different horse breeds. Specific characteristics of the walk, trot and canter are required for dressage. It has been assumed that some of these traits could be selected for genetically and contribute to dressage performance. The purpose of this study was to compare the walk, trot and conformation characteristics in young horses of different breeds used for dressage. A total of 142 horses age 3 years were classified into 3 groups of breeds (German, French and Spanish saddle horses) and tested using the same procedure. The skeletal conformation measurements were made by image analysis. Gait variables of the walk and trot were measured by the accelerometric gait analysis system Equimetrix. Discriminant analysis could explain the variability between the groups by taking into account the walk (P<0.0003), trot (P<0.0001) and conformation variables (P<0.0001). Many gait and conformation variables were significantly different between the breeds. In summary, the German horses had gait characteristics more adapted for dressage competition, and the results of this group could be used as a reference for early evaluation in dressage. Purebred Spanish horses could be considered as a reference for collected gaits used for farm work and old academic dressage. The gait and conformation tests could be applied in a breeding or crossing plan to detect more accurately young horses with good dressage ability.
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Becker-Birck, M., Biau, S., Aurich, C., Möstl, E., Ille, N., & Aurich, J. (2012). Heart rate and heart rate variability in the horse and its rider: different responses to training and a public equestrian performance. In K. Krueger (Ed.), Proceedings of the 2. International Equine Science Meeting (Vol. in press). Wald: Xenophon Publishing.
Abstract: While detailed information exists on the cardiovascular response of horses to racing or endurance, much less is known about cardiovascular function of the rider in equestrian sports. Combined analysis of the horse-rider-team has not been investigated so far. In this study, we have analyzed changes in heart rate and heart variability (HRV) variables SDRR (standard deviation of beat-to-beat interval) and RMSSD (root mean square of successive beat-to-beat intervals) both in well-trained horses (n=9) and their highly experienced riders (n=7) during the airs above the ground (sauteurs en liberté of the Cadre noir de Saumur) at a public performance and at an identical, but non-public training session, both lasting for exactly 7 min. Heart rate in the horses and riders increased during the airs above the ground, both in training and in the public performance (p<0.001 over time). In the horses, this increase did not differ between training and public performance (training: from 35±6 in the stable to 97±17 beats/min during riding, performance: from 43±13 to 103±13 beats/min, respectively). In contrast, in the riders, the increase in heart rate was significantly more pronounced (p<0.01) during the public performance (basal value 91±10, maximum 150±15 beats/min) than during training (basal value 94±10, maximum 118±12 beats/min). With regard to HRV in horses, overall SDRR did not change significantly over time and did not differ significantly between training and performance. RMSSD decreased during both training and performance to the same extent, indicating a decrease in parasympathetic (vagal) tone. In the riders, both HRV variables decreased significantly during riding (p<0.001) and for SDRR the decrease was more pronounced (p<0.05) during an equestrian performance compared to a training session. During the performance SDRR decreased from a basal value of 5.0±1.5 to a minimum of 3.2±0.6 msec while respective values for the training session were 5.3±1.1 and 2.3±1.1 msec. Both a public performance and an identical training session of the airs above the ground in the ridden horse caused an increase in heart rate and a decrease in HRV variables. While increases in heart rate are mainly caused by physical activity, decreases in HRV also indicate a stress response. The cardiovascular response in the horses did not differ between a training session and a public performance but clear differences could be demonstrated in the riders. During a public performance, the increase in heart rate and decrease in SDRR were more pronounced than during a similar training session. In conclusion, the presence of an audience thus causes more pronounced sympathoadrenal activity in experienced riders than the same equestrian tasks ridden without spectators present. In contrast, the presence of an audience was without effect on sympathoadrenal activity in experienced horses. KW -
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