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Author Palleroni, A.; Hauser, M.; Marler, P. doi  openurl
  Title Do responses of galliform birds vary adaptively with predator size? Type Journal Article
  Year 2005 Publication Animal Cognition Abbreviated Journal Anim. Cogn.  
  Volume 8 Issue 3 Pages (up) 200-210  
  Keywords Adaptation, Psychological; Animals; *Avoidance Learning; *Behavior, Animal; Body Size; Chickens; Female; Food Chain; Male; *Pattern Recognition, Visual; *Predatory Behavior; *Recognition (Psychology); Risk Assessment  
  Abstract Past studies of galliform anti-predator behavior show that they discriminate between aerial and ground predators, producing distinctive, functionally referential vocalizations to each class. Within the category of aerial predators, however, studies using overhead models, video images and observations of natural encounters with birds of prey report little evidence that galliforms discriminate between different raptor species. This pattern suggests that the aerial alarm response may be triggered by general features of objects moving in the air. To test whether these birds are also sensitive to more detailed differences between raptor species, adult chickens with young were presented with variously sized trained raptors (small, intermediate, large) under controlled conditions. In response to the small hawk, there was a decline in anti-predator aggression and in aerial alarm calling as the young grew older and less vulnerable to attack by a hawk of this size. During the same developmental period, responses to the largest hawk, which posed the smallest threat to the young at all stages, did not change; there were intermediate changes at this time in response to the middle-sized hawk. Thus the anti-predator behavior of the adult birds varied in an adaptive fashion, changing as a function of both chick age and risk. We discuss these results in light of current issues concerning the cognitive mechanisms underlying alarm calling behavior in animals.  
  Address Primate Cognitive Neuroscience Laboratory, Department of Psychology, Harvard University, 33 Kirkland St., Cambridge, MA, 02138, USA. aliparti@wjh.harvard.edu  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 1435-9448 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15660209 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2496  
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Author Reluga, T.C.; Viscido, S. doi  openurl
  Title Simulated evolution of selfish herd behavior Type Journal Article
  Year 2005 Publication Journal of Theoretical Biology Abbreviated Journal J. Theor. Biol.  
  Volume 234 Issue 2 Pages (up) 213-225  
  Keywords Selfish herd; Behavior; Evolution; Predation risk  
  Abstract Single species aggregations are a commonly observed phenomenon. One potential explanation for these aggregations is provided by the selfish herd hypothesis, which states that aggregations result from individual efforts to reduce personnel predation risk at the expense of group-mates. Not all movement rules based on the selfish herd hypothesis are consistent with observed animal behavior. Previous work has shown that herd-like aggregations are not generated by movement rules limited to local interactions between nearest neighbors. Instead, rules generating realistic herds appear to require delocalized interactions. To date, it has been an open question whether or not the necessary delocalization can emerge from local interactions under natural selection. To address this question, we study an individual-based model with a single quantitative genetic trait that controls the influence of neighbors as a function of distance. The results indicate that predation-based selection can increase the influence of distant neighbors relative to near neighbors. Our results lend support for the idea that selfish herd behavior can arise from localized movement rules under natural selection.  
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  Notes Approved no  
  Call Number refbase @ user @ Serial 553  
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Author Jackson, R.R.; Pollard, S.D.; Li, D.; Fijn, N. doi  openurl
  Title Interpopulation variation in the risk-related decisions of Portia labiata, an araneophagic jumping spider (Araneae, Salticidae), during predatory sequences with spitting spiders Type Journal Article
  Year 2002 Publication Animal Cognition Abbreviated Journal Anim. Cogn.  
  Volume 5 Issue 4 Pages (up) 215-223  
  Keywords Animals; Female; Male; Mental Processes; *Predatory Behavior; Risk Factors; *Spiders  
  Abstract The extent to which decision-making processes are constrained in animals with small brains is poorly understood. Arthropods have brains much smaller and simpler than those of birds and mammals. This raises questions concerning limitations on how intricate the decision-making processes might be in arthropods. At Los Banos in the Philippines, Scytodes pallidus is a spitting spider that specialises in preying on jumping spiders, and Portia labiata is a jumping spider that preys on S. pallidus. Scytodid spit comes from the mouth, and egg-carrying females are less dangerous than eggless scytodids because the female uses her chelicerae to hold her eggs. Held eggs block her mouth, and she has to release them before she can spit. The Los Banos P. labiata sometimes adjusts its tactics depending on whether the scytodid encountered is carrying eggs or not. When pursuing eggless scytodids, the Los Banos P. labiata usually takes detour routes that enable it to close in from behind (away from the scytodid's line of fire). However, when pursuing egg-carrying scytodids, the Los Banos P. labiata sometimes takes faster direct routes to reach these safer prey. The Los Banos P. labiata apparently makes risk-related adjustments specific to whether scytodids are carrying eggs, but P. labiata from Sagada in the Philippines (allopatric to Scytodes) fails to make comparable risk-related adjustments.  
  Address Department of Zoology, University of Canterbury, Private Bag 4800, Christchurch, New Zealand  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 1435-9448 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:12461599 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2591  
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Author Knubben, J.M.; Fürst, A.; Gygax, L.; Stauffacher, M. url  doi
openurl 
  Title Bite and kick injuries in horses: Prevalence, risk factors and prevention Type Journal Article
  Year 2008 Publication Equine Veterinary Journal Abbreviated Journal  
  Volume 40 Issue 3 Pages (up) 219-223  
  Keywords horse; kick; bite; injury; risk factors  
  Abstract Reasons for performing study: Studies on the prevalence and predisposing factors of bite and kick injuries in horses have not been reported in a population-based data sample. Objectives: To investigate the prevalence of bite and kick injuries in horses and associated risk factors in a representative sample of horses in Switzerland. Methods: A questionnaire on the incidence of disease and injury, which included the frequency of bite and kick injuries and their association with breed, housing, use and feeding regime, was sent to 2559 horse owners randomly selected throughout Switzerland. Results: The data of 2912 horses with 897 disorders diagnosed by a veterinarian were analysed. There were 231 injuries, 50 (21.6%) caused by a bite or kick from another horse; this number corresponded to 5.6% of all diseases and injuries and concerned only 1.7% of all the horses evaluated. Warmblood, Thoroughbred and Arabian horses had a 4.3 times higher risk of bite or kick injuries than horses of other breeds. Eighteen per cent of injuries were associated with a change in housing management and occurred regardless of whether horses were kept in groups permanently or sporadically. Conclusions and potential relevance: A stable group hierarchy and a housing system that provides adequate space and is adapted to horse-specific behaviour are important factors in prevention and kick and bite injuries.  
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  Publisher Blackwell Publishing Ltd Place of Publication Editor  
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  ISSN 2042-3306 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 5760  
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Author Fleurance, G.; Duncan, P.; Fritz, H.; Cabaret, J.; Cortet, J.; Gordon, I.J. url  doi
openurl 
  Title Selection of feeding sites by horses at pasture: Testing the anti-parasite theory Type Journal Article
  Year 2007 Publication Applied Animal Behaviour Science Abbreviated Journal Appl. Anim. Behav. Sci.  
  Volume 108 Issue 3-4 Pages (up) 228-301  
  Keywords Foraging strategies; Horses; Parasite risk; Patch choice  
  Abstract Management of grazed grasslands for production and/or conservation objectives requires a thorough understanding of the choices of feeding sites by herbivores, and of the biological processes involved. Most models of the feeding strategies of herbivores are based on the principle that optimising the intake of energy (or some nutrient) is the primary goal of foragers but other selective forces, such as parasitism, could be important. Gastrointestinal parasites (including cyathostome nematodes) have powerful effects on the fitness of herbivores and may act as a major selection pressure favouring host behaviour that reduces the risk of encountering parasites. Among large herbivores, horses have perhaps the most marked tendency to select particular feeding sites within grasslands. We test here: (1) whether horses select feeding patches with relatively low parasite densities and (2) if their choice is affected by their parasite load. We used 10 two-year old saddle-horses and three periods. In the first period, the horses were under natural parasitism which varied strongly among individuals; in the second period they were all dewormed, and in the third, a sub-set of the horses was experimentally infected with cyathostome larvae. Ninety-eight percent of the infective larvae in the pasture were found <1 m from faeces. The main determinant of the choice of feeding patch by horses was the availability of patches of different parasite risk and grass height. Controlling for availability, the horses used tall grasses (>16 cm) less than expected, whether the grass was contaminated or not, and they selected for short patches >1 m from faeces, where the risk of encountering parasites was low. These results suggest that selection of feeding sites by horses is driven by an interaction between their nutritional and anti-parasite strategies: the horses avoid the patches of tall grass which are generally of low quality and areas contaminated by parasite larvae which leads them to prefer the patches of short grass far from faeces. The parasite status of the horses at the time of the experiment had no effect on their feeding choices. However, before concluding that the challenge by cyathostomes has no effect on the selection of feeding sites in horses, it will be necessary to test whether the history of parasitism of the individuals, rather than the current status, is important.  
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  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 4228  
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Author Dugatkin, L.A.; Godin, G.J. doi  openurl
  Title Predator inspection, shoaling and foraging under predation hazard in the Trinidadian guppy,Poecilia reticulata Type Journal Article
  Year 1992 Publication Environmental Biology of Fishes Abbreviated Journal  
  Volume 34 Issue 3 Pages (up) 265-276  
  Keywords Antipredation – Social group – Feeding – Predation risk – Trade-off – Fish  
  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.  
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  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 2176  
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Author Lee, J.; Paik, M. openurl 
  Title Sex preferences and fertility in South Korea during the year of the Horse Type Journal Article
  Year 2006 Publication Demography Abbreviated Journal Demography  
  Volume 43 Issue 2 Pages (up) 269-292  
  Keywords Asian Continental Ancestry Group/*psychology; *Astrology; Attitude/*ethnology; Chronology; *Culture; Female; *Fertility; Humans; Korea; Male; *Mythology; Risk; *Sex Ratio; Social Desirability; Time  
  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.  
  Address Department of Economics, Sam M. Walton College of Business, Business Building 402, University of Arkansas, Fayetteville, AR 72701-1201, USA. jlee@walton.uark.edu  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0070-3370 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16889129 Approved no  
  Call Number Serial 1867  
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Author Atwill, E.R.; Mohammed, H.O.; Lopez, J.W. openurl 
  Title Evaluation of travel and use as a risk factor for seropositivity to Ehrlichia risticii in horses of New York state Type Journal Article
  Year 1996 Publication American Journal of Veterinary Research Abbreviated Journal Am J Vet Res  
  Volume 57 Issue 3 Pages (up) 272-277  
  Keywords Animals; Cross-Sectional Studies; Ehrlichiosis/epidemiology/*veterinary; Female; *Horse Diseases; Horses; Male; New York/epidemiology; Probability; Random Allocation; Risk Factors; *Travel  
  Abstract OBJECTIVES--To determine whether mean annual frequency and destination of equine travel was associated with exposure to Ehrlichia risticii and whether these associations were modified by horses' place of residence. DESIGN--Cross-sectional study. SAMPLE POPULATION--511 equine operations containing 2,587 horses were visited in New York state from a target population of 39,000 operations. PROCEDURE--Each horse was tested for serum antibodies against E risticii, using indirect fluorescent antibody. Information on the horse's travel history, farm's management practices, and surrounding ecology was obtained by personal interview and resource maps. Statistical analyses were performed on 2 cohorts of animals: all horses enrolled in the study and horses born on the property or that resided at least 4 years on the farm. Three county-based risk regions (RR) were identified by use of cluster analysis. RESULTS--Mean seroprevalence for each of the 3 RR was 2.4 (low risk), 8.5 (moderate risk), and 18.5% (high risk) for cohort 1 and 2.5, 8.0, and 18.4% for cohort 2. Among cohorts 1 and 2, pleasure riding and breeding trips were associated with exposure to E risticii, but horse residence (low, moderate, or high RR) was an effect modifier for these associations. Among cohort 1 and stratifying the analysis according to the RR for the travel destination, trail riding at low RR and trail riding at high RR were associated with exposure. Among cohort 2 and stratifying the analysis according to the RR for the travel destination, breeding trips were associated with exposure, and strong effect modification was present for horse residence (low, moderate, or high RR). CONCLUSIONS--Only certain types of travel to specific RR were associated with higher risk of exposure to E risticii. In many instances, travel was not associated, or was associated, with a reduced risk of exposure.  
  Address Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 0002-9645 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:8669754 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2658  
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Author Boden, L.A.; Anderson, G.A.; Charles, J.A.; Morgan, K.L.; Morton, J.M.; Parkin, T.D.H.; Slocombe, R.F.; Clarke, A.F. openurl 
  Title Risk of fatality and causes of death of Thoroughbred horses associated with racing in Victoria, Australia: 1989-2004 Type Journal Article
  Year 2006 Publication Equine Veterinary Journal Abbreviated Journal Equine Vet J  
  Volume 38 Issue 4 Pages (up) 312-318  
  Keywords Animals; Athletic Injuries/epidemiology/mortality/*veterinary; *Cause of Death; Female; *Floors and Floorcoverings; Horses/*injuries; Male; Physical Conditioning, Animal/*adverse effects; Risk Factors; Running/injuries; Safety; Sports; Victoria  
  Abstract REASONS FOR PERFORMING STUDY: Determining the risk of fatality of Thoroughbred horses while racing is essential to assess the impact of intervention measures designed to minimise such fatalities. OBJECTIVES: To measure the risk of racehorse fatality in jump and flat starts on racecourses in Victoria, Australia, over a 15 year period and to determine proportional mortality rates for specific causes of death. METHODS: All fatalities of Thoroughbred horses that occurred during or within 24 h of a race were identified from a database. The risk of a start resulting in a racehorse fatality in all races and within flat and jump races, proportional mortality rates, population attributable risk, population attributable fraction and risk ratios were calculated along with 95% confidence intervals. Poisson regression was also performed to estimate risk ratios. RESULTS: There were 514 fatalities over the 15 year period; 316 in flat races and 198 in jump races. The risk of fatality was 0.44 per 1000 flat starts and 8.3 per 1000 jump starts (18.9 x greater). The risk of fatality on city tracks was 1.1 per 1000 starts whereas on country tracks it was 0.57 per 1000 starts. Of the 316 fatalities in flat races, 73.4% were due to limb injury, 2.5% to cranial or vertebral injury and 19.0% were sudden deaths. Of the 198 fatalities in jump races, 68.7% were due to limb injury, 16.2% to cranial or vertebral injury and 3.5% were sudden deaths. The risk of fatality in flat starts increased between 1989 and 2004 but the risk in jump starts remained unchanged over the 15 year period. CONCLUSIONS: The risk of fatality in flat starts was lower in Victoria than North America and the UK but the risk in jump starts was greater. Catastrophic limb injury was the major reason for racehorse fatality in Victoria but there was a larger percentage of sudden deaths than has been reported overseas. The risk of fatality in jump starts remained constant over the study period despite jump racing reviews that recommended changes to hurdle and steeple races to improve safety. POTENTIAL RELEVANCE: This study provides important benchmarks for the racing industry to monitor racetrack fatalities and evaluate intervention strategies.  
  Address Department of Veterinary Science, The University of Melbourne, Werribee, Victoria, Australia  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 0425-1644 ISBN Medium  
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  Notes PMID:16866197 Approved no  
  Call Number Equine Behaviour @ team @ Serial 3761  
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Author Murray, J.K.; Singer, E.R.; Morgan, K.L.; Proudman, C.J.; French, N.P. doi  openurl
  Title Risk factors for cross-country horse falls at one-day events and at two-/three-day events Type Journal Article
  Year 2005 Publication The Veterinary Journal Abbreviated Journal  
  Volume 170 Issue 3 Pages (up) 318-324  
  Keywords Horse; Eventing; Fall; Cross-country; Risk  
  Abstract The cross-country phase of eventing competitions has been associated with injuries and fatalities to horses and riders. A case-control study was carried out to identify variables that were associated with increased or decreased risk of a horse fall on the cross-country phase at event competitions. After initial analysis, the dataset was split according to the categories of one-day events as compared to two- or three-day events to establish whether significant risk factors varied between the different types of eventing competitions. Data were collected for 121 cases (horse falls) at one-day events, 59 cases at two- or three-day events and for their 540 matched controls. The data were analysed using conditional logistic regression. The variables of no previous refusals on the course, fences with a landing in water and the combined variable of the angle and the spread of the fence were significantly associated with the risk of a horse fall in both datasets. Additional risk factors for one-day event falls were: fences requiring a take-off from water, a drop landing, the rider's knowledge of their position before the cross-country phase and if the rider received cross-country tuition. Three-day event risk factors in the multivariable model included: the camber of the fence and participation in non-equestrian sports by the rider. This study identified variables that were significantly associated with an increase or a decrease in the risk of a horse fall during the cross-country phase of different types of eventing competitions. Some of these variables are modifiable and the results of this study have been reported to the governing body of the sport of eventing in the UK so that possible interventions might be considered.  
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  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 3671  
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