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Pinchbeck, G. L., Clegg, P. D., Proudman, C. J., Morgan, K. L., & French, N. R. (2004). Whip use and race progress are associated with horse falls in hurdle and steeplechase racing in the UK. Equine Vet J, 36(5), 384–389.
Abstract: REASONS FOR PERFORMING STUDY: Falls during racing present a risk of injury to both horse and jockey and a risk of fatality to horses. OBJECTIVES: To use video recordings of races to describe the circumstances surrounding horse falls at hurdle and steeplechase fences and to identify and quantify within-race risk factors for horse falls in National Hunt racing in the UK. METHODS: A retrospective, matched, nested case-control study using video recordings of races was conducted on 6 UK racecourses. Cases and controls were matched on both race type and jump number at which the fall occurred. Conditional logistic regression analysis was used to examine the univariable and multivariable relationship between predictor variables and the risk of falling. RESULTS: The risk of falling was significantly associated with whip use and race progress. Horses which were being whipped and progressing through the race were at greater than 7 times the risk of falling compared to horses which were not being whipped and which had no change in position or lost position through the field. CONCLUSIONS: This study has identified whip use and the position of the horse with respect to others in the field as potential risk factors for horse falls. POTENTIAL RELEVANCE: If these findings are confirmed by the use of intervention trials (e.g. with whip-free or restricted whip use races), modifications could be introduced which would reduce the frequency of horse falls, leading to improved equine welfare.
Keywords: Accidental Falls/*statistics & numerical data; Animals; Athletic Injuries/epidemiology/etiology/*veterinary; Case-Control Studies; Cohort Studies; Great Britain/epidemiology; Horses/*injuries; Logistic Models; Odds Ratio; Retrospective Studies; Risk Factors; Running/statistics & numerical data; Sports; Videotape Recording
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Pinchbeck, G. L., Clegg, P. D., Proudman, C. J., Morgan, K. L., & French, N. P. (2004). A prospective cohort study to investigate risk factors for horse falls in UK hurdle and steeplechase racing. Equine Vet J, 36(7), 595–601.
Abstract: REASONS FOR PERFORMING STUDY: Equine fatalities during racing continue to be a major welfare concern and falls at fences are responsible for a proportion of all equine fatalities recorded on racecourses. OBJECTIVES: To identify and quantify risk factors for horse falls in National Hunt (NH) racing and to report the frequency of falling and falling-associated fatalities. METHODS: A prospective cohort study was conducted on 2879 horse starts in hurdle and steeplechase races on 6 UK racecourses. Any horse that suffered a fall at a steeplechase or hurdle fence during the race was defined as a case. Data were obtained by interview and observations in the parade ring and from commercial databases. Multivariable logistic regression models, allowing for clustering at the level of the track, were used to identify the relationship between variables and the risk of falling. RESULTS: There were 124 falling cases (32 in hurdling and 92 in steeplechasing) identified. The injury risk of fallers was 8.9% and fatality risk 6.5%. Duration of journey to the racecourse, behaviour in the parade ring and weather at the time of the race were associated with falling in both hurdle and steeplechase racing. Age, amount of rainfall and going were also associated with falling in steeplechase racing. CONCLUSIONS: Falls at fences are significant contributors to equine fatalities during NH racing. Potentially modifiable risk factors identified were the condition of track surfaces and journey time to the racecourse. POTENTIAL RELEVANCE: It is hoped that information from this study may be used in future interventions to improve horse and jockey safety in racing. The study has also identified areas requiring further research, such as equine behaviour and its effect on racing performance, and the effect of light conditions on jumping ability.
Keywords: *Accidental Falls/mortality/statistics & numerical data; Age Factors; Animal Welfare; Animals; Athletic Injuries/epidemiology/etiology/mortality/*veterinary; Cohort Studies; Great Britain; Horses/*injuries; Logistic Models; Odds Ratio; Prospective Studies; Questionnaires; Rain; Risk Factors; Safety; Sports
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Pinchbeck, G. L., Clegg, P. D., Proudman, C. J., Morgan, K. L., & French, N. P. (2004). Case-control investigation of the factors affecting the risk of horses falling during steeplechase racing in the UK. Vet. Rec., 155(1), 11–15.
Abstract: A concurrent case-control study of 12 UK racecourses was made between March 1, 2000, and August 31, 2001, to identify and quantify the factors associated with the risk of horses falling in steeplechase races. Cases were defined as a jumping effort at a steeplechase fence that resulted in a fall and controls were defined as a successful jumping effort over any steeplechase fence at any of the 12 racecourses within 14 days before or after the case fall. Information on the horse, the jockey and the race were collected and all the fences on all the courses were surveyed. Conditional logistic regression was used to examine the relationships between the predictor variables and the risk of falling. There was one fall per 254 jumping efforts. The risk of a horse falling decreased the more times it had raced on a particular racecourse. The number of fences, the distance from the previous fence and the nature of the previous fence also affected the risk of falling. If the previous fence was a water jump the risk of falling increased; fences that were sited on flat or slight uphill gradients (up to approximately 1 in 25) were associated with a lower risk of horses falling than downhill fences, and higher takeoff boards were associated with a higher risk of falling.
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Pinchbeck, G. L., Clegg, P. D., Proudman, C. J., Morgan, K. L., & French, N. P. (2003). Case-control study to investigate risk factors for horse falls in hurdle racing in England and Wales. Vet. Rec., 152(19), 583–587.
Abstract: Between March 1, 2000 and August 31, 2001, a case-control study was conducted on 12 racecourses in England and Wales to identify and quantify the risk factors associated with horse falls in hurdle races. The cases and controls were defined so that variables relating to the horse, the jockey, the race and racecourse, and the jump could be considered. The cases were defined as a jumping effort at a hurdle flight that resulted in a fall, and the controls were defined as a successful jump over a hurdle at any of the 12 racecourses within 14 days before or after the case fall. Conditional logistic regression was used to examine the univariable and multivariable relationships between the predictor variables and the risk of falling. The risk of falling was significantly associated with the position of the jump in the race, and with the distance and speed of the race. A horse's previous racing experience and history were also significantly associated with the risk of falling and horses participating in their first hurdle race were at almost five times greater risk of falling than horses that had hurdled before.
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Pick, D. F., Lovell, G., Brown, S., & Dail, D. (1994). Equine color perception revisited. Appl. Anim. Behav. Sci., 42(1), 61–65.
Abstract: An attempt to replicate Grzimek (1952; Z. Tierpsychol., 27: 330-338) is reported where a Quarter-Horse mare chose between colored and gray stimuli for food reinforcement. Stimuli varied across a broad range of reflectance values. A double-blind procedure with additional controls for auditory, olfactory, tactile, and position cues was used. The subject could reliably discriminate blue (462 nm) vs. gray, and red (700 nm) vs. gray without regard to reflectance (P<0.001), but could not discriminate green (496 nm) vs. gray. It is suggested that horses are dichromats in a manner similar to swine and cattle.
Keywords: Equine; Color perception; Dichromat
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Piccione, G., Caola, G., & Refinetti, R. (2005). Temporal relationships of 21 physiological variables in horse and sheep. Comp Biochem Physiol A Mol Integr Physiol, 142(4), 389–396.
Abstract: Daily or circadian oscillation has been documented in a variety of physiological and behavioral processes. Although individual variables have been studied in great detail, very few studies have been conducted on the temporal relationships between the rhythms of different variables. It is not known whether the circadian pacemaker generates each and every rhythm individually or whether most rhythms are simply derived from a few clock-controlled rhythms. As a first step in elucidating this issue, 21 physiological variables were recorded simultaneously in horse and sheep. The results indicated that, in both species, different variables exhibit different degrees of daily rhythmicity and reach their daily peaks at different times of the day. The variables exhibiting strongest rhythmicity were locomotor activity, rectal temperature, and plasma concentrations of melatonin and glucose. Comparison of rhythmicity and acrophase in the various rhythms allowed inferences to be made about mechanisms of causation.
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Phillips, C. J. C., Oevermans, H., Syrett, K. L., Jespersen, A. Y., & Pearce, G. P. (2015). Lateralization of behavior in dairy cows in response to conspecifics and novel persons. Journal of Dairy Science, 98(4), 2389–2400.
Abstract: Abstract The right brain hemisphere, connected to the left eye, coordinates fight and flight behaviors in a wide variety of vertebrate species. We investigated whether left eye vision predominates in dairy cows’ interactions with other cows and humans, and whether dominance status affects the extent of visual lateralization. Although we found no overall lateralization of eye use to view other cows during interactions, cows that were submissive in an interaction were more likely to use their left eye to view a dominant animal. Both subordinate and older cows were more likely to use their left eye to view other cattle during interactions. Cows that predominantly used their left eye during aggressive interactions were more likely to use their left eye to view a person in unfamiliar clothing in the middle of a track by passing them on the right side. However, a person in familiar clothing was viewed predominantly with the right eye when they passed mainly on the left side. Cows predominantly using their left eyes in cow-to-cow interactions showed more overt responses to restraint in a crush compared with cows who predominantly used their right eyes during interactions (crush scores: left eye users 7.9, right eye users 6.4, standard error of the difference = 0.72). Thus, interactions between 2 cows and between cows and people were visually lateralized, with losing and subordinate cows being more likely to use their left eyes to view winning and dominant cattle and unfamiliar humans.
Keywords: dairy cow; dominance; hemispheric processing; visual lateralization
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Peugnet, P., Wimel, L., Duchamp, G., Sandersen, C., Camous, S., Guillaume, D., et al. (2014). Enhanced or Reduced Fetal Growth Induced by Embryo Transfer into Smaller or Larger Breeds Alters Post-Natal Growth and Metabolism in Pre-Weaning Horses. PLoS ONE, 9(7), e102044 EP -.
Abstract: <p>In equids, placentation is diffuse and nutrient supply to the fetus is determined by uterine size. This correlates with maternal size and affects intra-uterine development and subsequent post-natal growth, as well as insulin sensitivity in the newborn. Long-term effects remain to be described. In this study, fetal growth was enhanced or restricted through ET using pony (P), saddlebred (S) and draft (D) horses. Control P-P (n = 21) and S-S (n = 28) pregnancies were obtained by AI. Enhanced and restricted pregnancies were obtained by transferring P or S embryos into D mares (P-D, n = 6 and S-D, n = 8) or S embryos into P mares (S-P, n = 6), respectively. Control and experimental foals were raised by their dams and recipient mothers, respectively. Weight gain, growth hormones and glucose homeostasis were investigated in the foals from birth to weaning. Fetal growth was enhanced in P-D and these foals remained consistently heavier, with reduced T3 concentrations until weaning compared to P-P. P-D had lower fasting glucose from days 30 to 200 and higher insulin secretion than P-P after IVGTT on day 3. Euglycemic clamps in the immediate post-weaning period revealed no difference in insulin sensitivity between P-D and P-P. Fetal growth was restricted in S-P and these foals remained consistently lighter until weaning compared to S-D, with elevated T3 concentrations in the newborn compared to S-S. S-P exhibited higher fasting glycemia than S-S and S-D from days 30 to 200. They had higher maximum increment in plasma glucose than S-D after IVGTT on day 3 and clamps on day 200 demonstrated higher insulin sensitivity compared to S-D. Neither the restricted nor the enhanced fetal environment affected IGF-1 concentrations. Thus, enhanced and restricted fetal and post-natal environments had combined effects that persisted until weaning. They induced different adaptive responses in post-natal glucose metabolism: an early insulin-resistance was induced in enhanced P-D, while S-P developed increased insulin sensitivity.</p>
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Petersen, J. L., Mickelson, J. R., Cothran, E. G., Andersson, L. S., Axelsson, J., Bailey, E., et al. (2013). Genetic Diversity in the Modern Horse Illustrated from Genome-Wide SNP Data. Plos One, 8(1), e54997.
Abstract: Horses were domesticated from the Eurasian steppes 5,000-6,000 years ago. Since then, the use of horses for transportation, warfare, and agriculture, as well as selection for desired traits and fitness, has resulted in diverse populations distributed across the world, many of which have become or are in the process of becoming formally organized into closed, breeding populations (breeds). This report describes the use of a genome-wide set of autosomal SNPs and 814 horses from 36 breeds to provide the first detailed description of equine breed diversity. FST calculations, parsimony, and distance analysis demonstrated relationships among the breeds that largely reflect geographic origins and known breed histories. Low levels of population divergence were observed between breeds that are relatively early on in the process of breed development, and between those with high levels of within-breed diversity, whether due to large population size, ongoing outcrossing, or large within-breed phenotypic diversity. Populations with low within-breed diversity included those which have experienced population bottlenecks, have been under intense selective pressure, or are closed populations with long breed histories. These results provide new insights into the relationships among and the diversity within breeds of horses. In addition these results will facilitate future genome-wide association studies and investigations into genomic targets of selection.
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Peters, G., & Tembrock, G. (1998). Subharmonics, biphonation, and deterministic chaos in mammal vocalizations. Bioacoustics, 9. |