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Dubois, C., & Ricard, A. (2007). Efficiency of past selection of the French Sport Horse: Selle Francais breed and suggestions for the future. Livestock Science, 112(1-2), 161–171.
Abstract: Parameters of genetic trend of Selle Francais (SF) horse breed were studied from 1974 to 2002 and detailed since 1991 because historical BLUP animal model genetic evaluation for jumping competition was available since 1989. During this period, annual births varied from 6000 to 10,000. The annual genetic trend for show jumping was 0.055 of genetic standard deviation between 1985 and 1995 and 0.096 since 1995 without unfavourable trend for dressage (ΔG = + 0.002) and eventing (ΔG = + 0.011). The three parameters of genetic trend: the selection intensity (i = 1.95 for males, 0.48 for females), the accuracy (r = 0.66 for males, 0.60 for females), and the generation interval (L = 12.0 years for males, 11.5 for females) explained this result. Particularities were: a higher number of progeny for best sires which induced true selection intensity equal to 2.21, a new and important selection on progeny (46% births form sires tested on progeny between 2000 and 2002), a high rate of own performance test in competition for mares (45%) which induced high accuracy of mare pathway. However, demographic possibilities were not reached, the possible selection rate for male (1.5%) and females (49%) should increase genetic gain + 14% and + 11% respectively. The generation interval was too long: a better selection at first stage for males, with equal rapid test on progeny and a shorter period of reproduction, i.e. a higher number of foals per sire, should decrease the relative importance of progeny test and should decrease generation interval. The drop of mares aged more than 10 at first progeny should decrease 1.2 year generation interval without loss on accuracy. If breeders keep the same structure (test of stallion and majority of mares on their own performance), they could add new criteria (conformation, gaits...) in the breeding value estimation for SF and maintain the high genetic trend on jumping.
Keywords: Horse; Genetic trend; Selection; Jumping
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Krueger, K. (2007). Behaviour of horses in the “round pen technique”. Appl. Anim. Behav. Sci., 104(1-2), 162–170.
Abstract: I investigated the behavioural background of the way horses learn to follow humans in the “round pen technique” suggested by “horse whisperers” as a gentle method for initial horse training. Though the practicability of this technique has been adequately demonstrated in the past, the horses' behaviour during such training has not yet been documented in detail. In a riding arena, horses, that did not follow the trainer immediately, were chased away so that they galloped around the trainer. Galloping horses showed specific behaviour such as turning the ear to the trainer, chewing, licking, and stretching head and throat downwards. In subsequent trials horses needed to be chased for less time and finally followed immediately, even when conditions were changed or the trainer was replaced by another person. This suggests that horses learn to follow in this particular situation and also show some generalisation. However, following did not occur on a pasture even after several successful trials in the riding arena.
Keywords: Learning; Dominance relationship; Horse; Human-animal relationships
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Balendra, G., Turner, M., McCrory, P., & Halley, W. (2007). Injuries in amateur horse racing (point to point racing) in Great Britain and Ireland during 1993-2006. Br J Sports Med, 41(3), 162–166.
Abstract: OBJECTIVES: To provide a breakdown of injury incidence from amateur jump racing (also known as point to point racing) in Great Britain and Ireland during 1993-2006 and to compare the injury epidemiology with professional horse racing in Great Britain, Ireland and France. DESIGN: Retrospective review. SETTING: Great Britain and Ireland. PARTICIPANTS: Amateur jockeys. MAIN OUTCOME MEASURES: Injury rates. RESULTS: Injury data suggest that point to point racing is more dangerous from an injury point of view than professional jump racing, which has previously been shown to be more dangerous than flat racing. Amateur jockeys have more falls than their professional counterparts, and this in turn puts them at greater risk of sustaining more serious injuries. CONCLUSIONS: Amateur (point to point) jockeys represent a sporting population that previously has been little studied. They represent a group at high risk of injury, and hence formal injury surveillance tracking and counter measures for injury prevention are recommended.
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Jorgensen, G. H. M., & Boe, K. E. (2007). A note on the effect of daily exercise and paddock size on the behaviour of domestic horses (Equus caballus). Appl. Anim. Behav. Sci., 107(1-2), 166–173.
Abstract: In a 2 x 3 factorial experiment we examined the effect of exercise (no exercise/daily exercise) and paddock size (small: 150 m2, medium: 300 m2 and large: 450 m2) on the behaviour of horses. In both these treatment periods nine (three cold blood and six warm blood) adult horses were exposed to all the three paddock size treatments for 2 h daily, for 1 week in each paddock size, and the order of paddock size treatments were rotated systematically. In between turnout in paddocks the horses were all housed in tie stalls. In the non-exercise period the horses walked significantly more, they travelled a longer distance, explored more and stood more alert, than in the period with exercise. The horses stood less passively in the large paddock compared to the medium and the small paddock, and they also travelled a longer distance in the larger paddock sizes. At days with heavy rain and wind, the horses were more restless and walked significantly more than in warmer weather. In conclusion; daily exercise significantly reduced the general activity in the paddocks. Increasing the paddock size to 450 m2, increased the time spent eating grass from under the fence and decreased the time spent standing passively.
Keywords: Horse; Exercise; Paddock size; Behaviour; Turnout
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Motch, S. M., Harpster, H. W., Ralston, S., Ostiguy, N., & Diehl, N. K. (2007). A note on yearling horse ingestive and agonistic behaviours in three concentrate feeding systems. Appl. Anim. Behav. Sci., 106(1-3), 167–172.
Abstract: The objective of this study was to compare behaviours of yearling horses fed concentrates under each of three management systems. Over two consecutive years, 16 yearling horses (n = 8/year; 4 fillies, 4 geldings, full siblings between years) were observed over a 60-day trial period/year at 15:30 h each day. The experimental design consisted of three factors (sex, feeder type, and year); repeated measures on feeder type: tire feeders (control system), individual tub feeders, and manger feeders. Frequency of agonistic interaction was affected by feeder type and sex. Fillies performed more than three times the total number of agonistic behaviours per feeding session as geldings. In both years, horses spent the most time eating and had the fewest agonistic interactions when fed in tire feeders.
Keywords: Horse; Feeding; Agonistic behaviour; Social behaviour; Sex differences
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Schmidt, R., Amrhein, V., Kunc, H. P., & Naguib, M. (2007). The day after: effects of vocal interactions on territory defence in nightingales. T. J. Anim. Ecol., 76(1), 168–173.
Abstract: 1. Models on territory acquisition and tenure predict that territorial animals benefit by adjusting territorial defence behaviour to previous challenges they had experienced within the socially complex environment of communication networks. 2. Here, we addressed such issues of social cognition by investigating persisting effects of vocal contests on territory defence behaviour in nightingales Luscinia megarhynchos (Brehm). 3. Using interactive playback during nocturnal song of subjects, a rival was simulated to countersing either aggressively (by song overlapping) or moderately (by song alternating) from outside the subjects' territory. Thereby, the time-specific singing strategy provided an experimentally controlled source of information on the motivation of an unfamiliar rival. 4. Expecting that nightingales integrate information with time, the same rival was simulated to return as a moderately singing intruder on the following morning. 5. The results show that the vigour with which male nightingales responded to the simulated intrusion of an opponent during the day depended on the nature of the nocturnal vocal interaction experienced several hours before. 6. Males that had received the song overlapping playback the preceding night approached the simulated intruder more quickly and closer and sang more songs near the loudspeaker than did males that had received a song alternating playback. 7. This adjustment of territory defence strategies depending on information from prior signalling experience suggests that integrating information with time plays an important part in territory defence by affecting a male's decision making in a communication network.
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Tanaka, M. (2007). Recognition of pictorial representations by chimpanzees (Pan troglodytes). Anim. Cogn., 10(2), 169–179.
Abstract: In this study, I investigated chimpanzees' ability to recognize pictorial representations. Four adults and three juvenile chimpanzees were trained to choose images of photographs of flowers among 12 items belonging to four categories on a touch-sensitive monitor. As a generalization test, the following five types of images were presented: (1) novel photographs, (2) colored sketches (more realistic), (3) a colored clip art (cartoon-like images), (4) black-and-white line drawings, and (5) Kanji characters (as the control images). One adult and all three juvenile chimpanzees were able to choose any style of the nonphotographic images of flowers significantly above the chance level, whereas none could choose the correct Kanji characters corresponding to a flower significantly above the chance level. The other three adult chimpanzees' performance level did not exceed the chance level in terms of choosing nonphotographic images although they showed good transfer skills to novel photographs. The results revealed that not all chimpanzees could recognize pictures used by humans without training. The results also suggest “critical period” in acquisition of skill in recognizing pictures in chimpanzees. Only one adult chimpanzee, who had acquired skill in recognizing visual symbols, also recognized pictures aside from the juvenile chimpanzees. Her learning history might have aided her in acquiring this skill. The results of this study suggest a relationship between pictorial competence and symbolic one.
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Bonnie, K. E., & Earley, R. L. (2007). Expanding the scope for social information use. Anim. Behav., 74(2), 171–18.
Abstract: Our understanding of how, why, and the circumstances under which animals use social information has been facilitated by three principal areas of research, social learning, public information use and social eavesdropping. With few exceptions, these related concepts have remained remarkably distinct within the literature, with little discussion or integration among them. Are these distinctions warranted? We tackle the issue by exploring similarities and differences between the concepts with respect to how animals gather and use social information, the type of information gathered, how information is packaged, and the relative payoffs to individuals involved. We contend that none of the currently dominant paradigms, social learning, public information use, or social eavesdropping, provide a unifying theme for studying social information use. Instead, we favour the central characteristic of the three concepts, social information use, as the overarching umbrella, and advocate a broader conceptual framework for understanding more comprehensively how animals behave with their social environments. Our intention is not to revolutionize the fields of social learning, public information use or social eavesdropping, but rather to stimulate discussion among researchers investigating the abilities of animals to extract information from the social environment.
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Stöwe, M. & K., K. (2007). Behavioural phenotypes may determine whether social context facilitates or delays novel object exploration in ravens. International Journal of Ornithology, 148(Suppl 2), 179–184.
Abstract: Individuals consistently differ in behavioural phenotypes. Here we examine the interaction between behavioural phenotype and response to social context during novel object exploration in a neophobic corvid species, the raven (Corvus corax). The presence of conspecifics tends to encourage object exploration and learning but may also delay or even inhibit exploratory behaviour. Factors such as individual differences in response to social context may determine whether the presence of a conspecific facilitates or inhibits approach to novel objects. We confronted eleven six-month-old hand-raised ravens with novel objects, both individually and in dyadic combinations. We defined individuals as “fast” and “slow” explorers on the basis of their approach latency to novel objects when tested individually. The presence of a conspecific delayed the approach of fast birds to novel objects. Slow birds, in contrast, approached the novel objects with lower latencies and spent more time close to them when in dyads with fast siblings than when alone. The individuals" approach behaviour seemed to determine whether social context facilitated or delayed exploratory behaviour. This may contribute to explaining ambiguous results concerning the effects of social context in previous studies.
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Petruso, E. J., Fuchs, T., & Bingman, V. P. (2007). Time-space learning in homing pigeons (Columba livia): orientation to an artificial light source. Anim. Cogn., 10(2), 181–188.
Abstract: Time-space learning reflects an ability to represent in memory event-stimulus properties together with the place and time of the event; a capacity well developed in birds. Homing pigeons were trained in an indoor octagonal arena to locate one food goal in the morning and a different food goal in the late afternoon. The goals differed with respect to their angular/directional relationship to an artificial light source located outside the arena. Further, the angular difference in reward position approximated the displacement of the sun's azimuth that would occur during the same time period. The experimental birds quickly learned the task, demonstrating the apparent ease with which birds can adopt an artificial light source to discriminate among alternative spatial responses at different times of the day. However, a novel midday probe session following successful learning revealed that the light source was interpreted as a stable landmark and not as a surrogate sun that would support compass orientation. Probe sessions following a phase shift of the light-dark cycle revealed that the mechanism employed to make the temporal discrimination was prevailingly based on an endogenous circadian rhythm and not an interval timing mechanism.
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