|
|
Nagy, K., Schrott, A., & Kabai, P. (2008). Possible influence of neighbours on stereotypic behaviour in horses. Appl. Anim. Behav. Sci., 111(3-4), 321–328.
Abstract: Revealing risk factors of abnormal stereotypic behaviour (ASB) in horses can help in the design of protective measures. Previous epidemiological studies indicate that social isolation, housing, management conditions, and feeding regime have a strong effect on developing ASB. The common belief that exposure to a stereotypic horse increases the risk of ASB has never been substantiated. Here we report that a generalised linear mixed models (GLMM) analysis of data on 287 horses of nine riding schools revealed that exposure to a stereotypic neighbour is a significant risk factor for performing stereotypy. Also, aggressive behaviour towards other horses increased the odds of stereotypy in the aggressor. These correspondences are unlikely to be a riding-school effect, because riding schools were treated as random factor in the GLMM. Risk factors identified by epidemiological studies cannot be treated as causal agents without independent evidence. Our aim in presenting these findings was to draw attention to the possibility of neighbour effects so that other researchers would include this variable in their surveys.
|
|
|
|
Pimenta, V., Barroso, I., Boitani, L., & Beja, P. (2018). Risks a la carte: Modelling the occurrence and intensity of wolf predation on multiple livestock species. Biol. Conserva., 228, 331–342.
Abstract: Predation on livestock is a source of human-wildlife conflicts and can undermine the conservation of large carnivores. To design effective mitigation strategies, it is important to understand the determinants of predation across livestock species, which often differ in husbandry practices, vulnerability to predators and economic value. Moreover, attention should be given to both predation occurrence and intensity, because these can have different spatial patterns and predictors. We used spatial risk modelling to quantify factors affecting wolf predation on five livestock species in Portugal. Within the 1619 parishes encompassing the entire wolf range in the country, the national wolf compensation scheme recorded 17,670 predation events in 2009-2015, each involving one or more livestock species: sheep (31.7%), cattle (27.7%), goats (26.8%), horses (14.8%) and donkeys (3.2%). Models built with 2009-2013 data and validated with 2014-2015 data, showed a shared general pattern of predation probability on each species increasing with its own density and proximity to wolf packs. For some species there were positive relations with the density of other livestock species, and with habitat variables such as altitude, and land cover by shrubland and natural pastures. There was also a general pattern for predation intensity on each species increasing with its own density, while proximity to wolf packs had no significant effects. Predation intensity on goats, cattle and horses increased with the use of communal versus private pastures. Our results suggest that although predation may occur wherever wolves coexist with livestock species, high predation intensity is mainly restricted to particular areas where husbandry practices increase the vulnerability of animals, and this is where mitigation efforts should concentrate.
|
|
|
|
Verheyen, K., Price, J., Lanyon, L., & Wood, J. (2006). Exercise distance and speed affect the risk of fracture in racehorses. Bone, 39(6), 1322–1330.
Abstract: In order to gain insight into those training regimens that can minimise the risk of fracture in athletic populations, we conducted a large epidemiological study in racehorses. Thoroughbred racehorses provide a suitable model for studying fracture development and exercise-related risk factors in physically active populations. They represent a homogeneous population, undertaking intensive exercise programmes that are sufficiently heterogeneous to determine those factors that influence injury risk. Daily exercise information was recorded for a cohort of 1178 thoroughbreds that were monitored for up to 2 years. A total of 148 exercise-induced fractures occurred in the study population. Results from a nested case-control study showed a strong interactive effect of exercise distances at different speeds on fracture risk. Horses that exceeded 44 km at canter (< or =14 m/s) and 6 km at gallop (>14 m/s) in a 30-day period were at particularly increased risk of fracture. These distances equate to ca. 7700 bone loading cycles at canter and 880 loading cycles at gallop. Fifty-six fractures occurred in the subset of study horses that were followed since entering training as yearlings, when skeletally immature (n = 335). Cohort analysis of this data set showed that, in previously untrained bones, accumulation of canter exercise increased the risk of fracture (P < or = 0.01), whereas accumulation of high-speed gallop exercise had a protective effect (P < 0.01). However, increasing distances at canter and gallop in short time periods (up to one month) were associated with an increasing fracture risk. All training exercise involves a balance between the risk of fracture inherent in exposure to loading and the beneficial effect that loading has by stimulating bone cells to produce a more robust architecture. Results from our study provide important epidemiological evidence of the effects of physical exercise on bone adaptation and injury risk and can be used to inform the design of safer exercise regimens in physically active populations.
|
|
|
|
Endy, T. P., & Nisalak, A. (2002). Japanese encephalitis virus: ecology and epidemiology. Curr Top Microbiol Immunol, 267, 11–48.
|
|
|
|
Lee, J., & Paik, M. (2006). Sex preferences and fertility in South Korea during the year of the Horse. Demography, 43(2), 269–292.
Abstract: Since antiquity, people in several East Asian countries, such as China, Japan, and South Korea, have believed that a person is destined to possess specific characteristics according to the sign of the zodiac under which he or she was born. South Koreans, in particular, have traditionally considered that the year of the Horse bears inauspicious implications for the birth of daughters. Using monthly longitudinal data at the region level in South Korea between 1970 and 2003, we found that in the year of the Horse, the sex ratio at birth significantly increased while fertility decreased.
|
|
|
|
Heitkamp, H. C., Horstmann, T., & Hillgeris, D. (1998). [Riding injuries and injuries due to handling horses in experienced riders]. Unfallchirurg, 101(2), 122–128.
Abstract: A group of experienced riders who qualified for the German riding badge 9.5 years ago answered a questionnaire pertaining to injuries during jumping, dressage and cross-country riding, as well as handling the horse. During riding 69% of the persons had had 187 injuries and while handling the horse 52% had had 124 injuries. Fractures and contusions were the most-frequent injuries; most riding injuries were located in the upper extremities and shoulder while handling mainly in the hands and feet. The number of injuries was comparable in jumping, dressage or cross-country riding. The time engaged in jumping was about one-third of the other types of riding, but the injuries were more severe. While handling the horse the number of injuries relative to the time spent during the activity were higher but less complicated. No change in safety precautions had been implemented by 67% of the persons injured. The injury rate for equestrians is relatively low both in handling the horse and during riding. The frequent fractures and contusions may be reduced by following the required safety regulations.
|
|
|
|
Dugatkin, L. A., & Godin, G. J. (1992). Predator inspection, shoaling and foraging under predation hazard in the Trinidadian guppy,Poecilia reticulata. Environmental Biology of Fishes, 34(3), 265–276.
Abstract: Guppies,Poecilia reticulata, living in stream pools in Trinidad, West Indies, approached a potential fish predator (a cichlid fish model) in a tentative, saltatory manner, mainly as singletons or in pairs. Such behavior is referred to as predator inspection behavior. Inspectors approached the trunk and tail of the predator model more frequently, more closely and in larger groups than they approached the predator's head, which is presumably the most dangerous area around the predator. However, guppies were not observed in significantly larger shoals in the stream when the predator model was present. In a stream enclosure, guppies inspected the predator model more frequently when it was stationary compared to when it was moving, and made closer inspections to the posterior regions of the predator than to its head. Therefore, the guppies apparently regarded the predator model as a potential threat and modified their behavior accordingly when inspecting it. Guppies exhibited a lower feeding rate in the presence of the predator, suggesting a trade-off between foraging gains and safety against predation. Our results further suggest that predator inspection behavior may account for some of this reduction in foraging. These findings are discussed in the context of the benefits and costs of predator inspection behavior.
|
|
|
|
Waters, A. J., Nicol, C. J., & French, N. P. (2002). Factors influencing the development of stereotypic and redirected behaviours in young horses: findings of a four year prospective epidemiological study. Equine Vet J, 34(6), 572–579.
Abstract: Stereotypies are invariant and repetitive behaviour patterns that seemingly have no function, which tend to develop in captive animals faced with insoluble problems and may be indicative of reduced welfare. A 4 year prospective study of the factors influencing the development of stereotypic and redirected behaviours (abnormal behaviour) in a population of 225 young Thoroughbred and part-Thoroughbred horses was conducted between 1995 and 1999. Abnormal behaviour affected 34.7% of the population. Multivariable analysis showed that foals of low- or middle-ranking mares were less likely to develop abnormal behaviour than foals of dominant mares (rate ratio (RR) 0.23, P<0.01; RR 0.48, P<0.01, respectively). Weaning by confinement in a stable or barn was associated with an increased rate of development of abnormal behaviour, compared with paddock-weaning (RR 2.19, P<0.05), and housing in barns, rather than at grass after weaning, was associated with a further increase (RR 2.54, P<0.01). Specific stereotypic and redirected behaviours were then considered as separate outcomes. Crib-biting was initiated by 10.5% of horses at median age 20 weeks, weaving by 4.6% of horses at median age 60 weeks, box-walking by 2.3% of horses at median age 64 weeks and wood-chewing by 30.3% of horses at median age 30 weeks. Wood-chewing developed at a lower rate in horses born to subordinate or mid-ranking mares than in horses born to dominant mares (RR 0.29, P<0.01; RR 0.41, P<0.01, respectively), and at a higher rate in horses kept in barns or stables rather than at grass after weaning (RR 4.49, P<0.001; RR 1A6, P<0.001, respectively). Feeding concentrates after weaning was associated with a 4-fold increase in the rate of development of crib-biting (RR 4.12, P = 0.02). The results of this study support the idea that simple changes in feeding, housing and weaning practices could substantially lower the incidence of abnormal behaviour in young horses.
|
|
|
|
McGreevy, P. D., Cripps, P. J., French, N. P., Green, L. E., & Nicol, C. J. (1995). Management factors associated with stereotypic and redirected behaviour in the thoroughbred horse. Equine Vet J, 27(2), 86–91.
Abstract: A greater knowledge of the effect of management factors is required to investigate the ontogeny of abnormal behaviour in the stabled horse. A postal survey of racehorse (flat) trainers yielded information about 22 yard and management factors. The relationship of the factors to the prevalence of abnormal behaviour was analysed by logistic regression. Management factors related to the time spent in the stable showed the strongest associations with stereotypic behaviour. The risk of horses performing abnormal behaviour increased: 1) as the amount of forage fell below 6.8 kg/day, 2) when bedding types other than straw were used, 3) when the total number of horses on the yard was fewer than 75, 4) in association with box designs that minimised contact between neighbouring horses, 5) when hay, rather than other types of forage, was used.
|
|
|
|
Senior, J. M., Pinchbeck, G. L., Allister, R., Dugdale, A. H. A., Clark, L., Clutton, R. E., et al. (2006). Post anaesthetic colic in horses: a preventable complication? Equine Vet J, 38(5), 479–484.
Abstract: REASONS FOR PERFORMING STUDY: There is little information on the prevalence of, and risk factors associated with, post anaesthetic colic (PAC) in horses undergoing nonabdominal operations. OBJECTIVES: To undertake the first prospective study of prevalence of PAC and identify risk factors in its development in nonabdominal procedures. METHODS: A multicentre prospective case-control study was conducted, on every horse undergoing anaesthesia for a nonabdominal procedure between April 2004 and June 2005. Colic cases were defined as any horse with recognised signs of abdominal pain within 72 h of general anaesthesia that could not be attributed to any concurrent disease. Five control horses per case were selected randomly from the study population at all hospitals. Multivariable logistic regression analysis was used to examine the relationship between predictor variables and the risk of developing PAC. RESULTS: The estimated mean prevalence of PAC in the study population was 5.2% (95% CI, 2.8, 8.0). However, the prevalence of colic varied between each centre. The most commonly diagnosed cause of colic was impaction. Multivariable analyses showed that the centre involved and the type of surgery performed were associated with an increased risk of PAC. Preoperative food deprivation and the use of opioid drugs were confounding factors. CONCLUSIONS: Prevalence of PAC varied significantly between the 4 hospitals studied; there may be hospital-related covariates that account for this. The type of surgery performed influenced the risk of PAC. POTENTIAL RELEVANCE: Identifying the risk factors for PAC is a prerequisite for its prevention. This study indicates horses at increased risk of PAC that might benefit from a more critical evaluation of post anaesthetic gastrointestinal function and/or the provision of preventative measures. Further investigation is required to explain the variation in prevalence of PAC between centres.
|
|
