Abstract: Video analysis was used to measure temporal characteristics of the collected walk, extended walk and half pirouette at walk of eleven competitors during the team dressage competition at the 1996 Summer Olympic Games in Atlanta, GA. Forelimb stance durations, hind limb stance durations, lateral step intervals and diagonal step intervals were symmetrical for the right and left sides in the collected and extended walk strides, but there were left-right asymmetries in the forelimb stance duration and in the lateral step interval in the half pirouette strides. For both collected and extended walk strides, hind limb stance duration was significantly longer than forelimb stance duration. The mean values for the group of eleven horses showed that the collected and extended walks had a regular rhythm. The half pirouette strides showed an irregularity in which there was a short interval between footfalls of the outside forelimb and inside hind limb, and along interval between footfalls of the inside hind limb and inside forelimb. This irregularity reflected an early placement of the inside hind limb. The stance times of both hind limbs were prolonged and this finding, in combination with the early placement of the inside hind limb, led to an increase in the period of tripedal support in each stride of the half pirouette. This was interpreted as a means of maintaining the horses' balance in the absence of forward movement.

Abstract: Forty-one Dutch Warmblood immature horses were used in a study to quantify temperamental traits on the basis of heart rate (HR) and heart rate variability (HRV) measures. Half of the horses received additional training from the age of 5 months onwards; the other half did not. Horses were tested at 9, 10, 21 and 22 months of age in a novel object and a handling test. During the tests, mean HR and two heart variability indices, e.g. standard deviation of beat-to-beat intervals (SDRR) and root mean square of successive beat-to-beat differences (rMSSD), were calculated and expressed as response values to baseline measures. In both tests, horses showed at all ages a significant increase in mean HR and decrease in HRV measures, which suggests a marked shift of the balance of the autonomic nervous system towards a sympathetic dominance. In the novel object test, this shift was more pronounced in horses that had not been trained. Furthermore, statistical analysis showed that the increase in mean HR could not be entirely explained by the physical activity. The additional increase in HR, the nonmotor HR, was more pronounced in the untrained horses compared to the trained. Hence, it is suggested that this nonmotor HR might be due to the level of emotionality. HR variables showed consistency between years, as well as within the second year. These tests bring about a HR response in horses, part of which may indicate a higher level of emotionality; and horses show individual consistency of these HR variables over ages. Therefore, it is concluded that mean HR and HRV measures used with these tests quantify certain aspects of a horse's temperament.

Abstract: The horse's temperament, including its manageability and reactivity and/or fearfulness, is of importance as it can result in problems and can render horses unsuitable for inexperienced riders. Early experience, including handling during infancy, may influence the horse's adult behaviour and reduce its fear of humans and other potentially frigthening situations. In the various species studied, handling has generally been undertaken during the neonatal period. The aim of the present study was to test the effects of handling young horses around the time of weaning, a period which has been demonstrated to be effective in increasing ease of handling in cattle and goats. Sixteen Anglo-Arab foals were handled for 12 days either immediately following weaning (early handled: EH) or 21 days later (late handled: LH); eight additional non-handled foals served as controls (C). Handling consisted of haltering, gently petting all parts of the body, picking up feet and leading the foal over 120 m. During handling sessions, EH were easier to handle than LH: time taken to fit them with a halter, to pick up feet, and “walk-ratio” (time walking under constraint/total time walking) were significantly lower for EH. During subsequent tests conducted over 2 days, 4, and 7 months, as well as 10 months and to some extent 18 months after the end of handling period, EH and LH were easier to handle and less reactive than controls, although differences diminished with time. The period following weaning can therefore be qualified as an “optimal period” for handling. Some of the effects persist for at least 18 months.

Abstract: Leadership is not an inherent quality of animal groups that show directional locomotion. However, there are other factors that may be responsible for the occurrence of leadership in fish shoals, such as individual differences in nutritional state between group members. It appears that front fish have a strong influence on directional shoal movements and that individuals that occupy such positions are often characterised by larger body lengths and lower nutritional state. Potential interactions between the two factors and their importance for positioning within shoals need further attention. Initiation of directional movement in stationary shoals and position preferences in mobile shoals need to be addressed separately because they are potentially subject to different constraints. Individuals that initiate a swimming direction may not necessarily be capable of the sustained high swimming performance required to keep the front position or have the motivation to do so, for that matter. More empirical and theoretical work is necessary to look at the factors controlling positioning behaviour within shoals, as well as overall shoal shape and structure. Tracking of marked individuals whose positioning behaviour is monitored over extended time periods of hours or days would be useful. There is an indication that shoal positions are rotated by individuals according to their nutritional needs, with hungry fish occupying front positions only for as long as necessary to regain their nutritional balance. This suggests that shoal members effectively take turns at being leaders. There is a need for three-dimensional recordings of shoaling behaviour using high-speed video systems that allow a detailed analysis of information transfer in shoals of different size. The relationship between leadership and shoal size might provide an interesting field for future research. Most studies to date have been restricted to shoals of small and medium size and more information on larger shoals would be useful.

Abstract: Four methods of ranking horses on reactivity were evaluated and compared: isolation from conspecifics, presentation of a static novel stimulus, traversing a novel stimulus in a runway (isolation, novel stimulus and runway tests, respectively) and assigning subjective emotionality scores. In all tests, horses' heart rates were recorded and behaviour was videotaped. To be considered a valid test of reactivity, at least one heart rate and one behavioural measurement in the test had to change significantly between treatments (tranquilizer administation versus sham tranquilizer administration), and behavioural measures had to be displayed in at least 75% of the trials. Forty horses performed each of the three tests daily on three different days in a switchback design. Horses were assigned randomly to a daily test sequence, which was maintained throughout the study. In the runway test, no significant difference in heart rate values in tranquilized and non-tranquilized horses was found, and no behavioural attribute was displayed in more than 52% of the trials; therefore it was rejected as a valid test of reactivity. Both isolation and novel stimulus tests produced valid measurements. Mean heart rate was the most precise physiological measure for these tests, and walking and defecation frequency were the most precise behavioural measures for novel stimulus and isolation tests, respectively. Mean heart rates on the novel stimulus and isolation tests were correlated (rs = 0.79, P < 0.01) indicating that these tests produced similar rankings based on physiological responses. However, behavioural measures ranked horses differently (rs = 0.27, P < 0.10) on the tests. Rank correlations between mean heart rates and behavioural measures were higher in the novel stimulus (rs = 0.66, P < 0.01) than the isolation test (rs = 0.55, P < 0.01), indicating that the novel stimulus test ranked horses based on either physiological or behavioural responses more similarly than did the isolation test. Therefore, the novel stimulus test was considered the more accurate evaluation of reactivity. Subjective emotionality scores were correlated moderately with mean heart rates (rs > 0.33, P < 0.01) from the novel stimulus and isolation tests and with walking scores (rs = 0.47, P < 0.01) from the novel stimulus test. Assignment of subjective emotionality scores was not as accurate as the novel stimulus or isolation tests in ranking horses for reactivity. Using physiological data alone, combining physiological and behavioural measurements or using more than one behavioural measurement in reactivity tests may reflect the reactivity of the horse better than a single behavioural measurement.