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Madigan, J. E., Kortz, G., Murphy, C., & Rodger, L. (1995). Photic headshaking in the horse: 7 cases. Equine Vet J, 27(4), 306–311.
Abstract: Seven horses with headshaking are described. No physical abnormalities were detected in any of the cases. Six of these horses had onset of clinical signs in the spring. The role of light was assessed by application of a blindfold or dark grey lens to the eyes, covering the eyes with a face mask and observing the horse in total darkness outdoors. Cessation of headshaking was observed with blindfolding (5/5 horses), night darkness outdoors (4/4 horses) and use of grey lenses (2/3 horses). Outdoor behaviour suggested efforts to avoid light in 4/4 cases. The photic sneeze in man is suggested as a putative mechanism for equine headshaking. Five of 7 horses had improvement with cyproheptadine treatment (0.3 mg/kg bwt b.i.d.). Headshaking developed within 2 calendar weeks of the same date for 3 consecutive years in one horse. Neuropharmacological alterations associated with photoperiod mechanisms leading to optic trigeminal summation are suggested as possible reasons for spring onset of headshaking.
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Marc, M., Parvizi, N., Ellendorff, F., Kallweit, E., & Elsaesser, F. (2000). Plasma cortisol and ACTH concentrations in the warmblood horse in response to a standardized treadmill exercise test as physiological markers for evaluation of training status. J. Anim Sci., 78(7), 1936–1946.
Abstract: Reliable physiological markers for performance evaluation in sport horses are missing. To determine the diagnostic value of plasma ACTH and cortisol measurements in the warmblood horse, 10 initially 3-yr-old geldings of the Hannovarian breed were either exposed to a training schedule or served as controls. During experimental Phase 1, horses were group-housed, and half of the horses were trained for 20 wk on a high-speed treadmill. During Phase 2, groups were switched and one group was trained for 10 wk as during Phase 1, whereas the control group was confined to boxes. During Phase 3 horses were initially schooled for riding. Thereafter, all horses were regularly schooled for dressage and jumping, and half of the horses received an additional endurance training for 24 wk. During all phases horses were exposed at regular intervals to various standardized treadmill exercise tests. During and after the tests frequent blood samples were taken from an indwelling jugular catheter for determination of ACTH and cortisol. Treadmill exercise increased both hormones. Maximum ACTH concentrations were recorded at the end of exercise, and maximum cortisol levels were recorded 20 to 30 min later. Except for one test there were no differences in ACTH levels between trained horses and controls. There was no significant effect of training on the cortisol response (net increase) to treadmill exercise in any of the tests during Phase 1. During Phase 2 higher cortisol responses were recorded in controls than in trained horses (P < .05) after 10 wk of training (controls confined to boxes). During Phase 3 plasma cortisol responses were also higher in controls than in trained horses (P < .05 after 6, 18, and 24, P < or = .07 after 12 wk of training) when the inclination of the treadmill was 5%, but not at 3%. There was no overlap in net cortisol responses at 30 min between trained and untrained horses. An ACTH application after 24 wk of training resulted in higher cortisol responses in controls than in trained horses (P < or = .05), without any overlap between the groups at 30 min after ACTH. Plasma cortisol responses to either treadmill exercise or ACTH injection may be a reliable physiological marker for performance evaluation. Prerequisites are sufficient differences in training status and sufficient intensity of exercise test conditions.
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Broekhuis, F., Madsen, E. K., & Klaassen, B. (2019). Predators and pastoralists: how anthropogenic pressures inside wildlife areas influence carnivore space use and movement behaviour. Anim Conserv, .
Abstract: Abstract Across the globe, wildlife populations and their behaviours are negatively impacted by people. Protected areas are believed to be an antidote to increasing human pressures but even they are not immune to the impact of anthropogenic activities. Areas that have been set aside for the protection of wildlife therefore warrant more attention when investigating the impact of anthropogenic pressures on wildlife. We use cheetahs Acinonyx jubatus as a case study to explore how a large carnivore responds to anthropogenic pressures inside wildlife areas. Using GPS-collar data we investigate cheetah space use, both when moving and stationary, and movement parameters (speed and turn angles) in relation to human disturbance, distance to human settlement, livestock abundance and livestock site use inside wildlife areas. Space use was negatively influenced by human disturbance, resulting in habitat loss and fragmentation and potentially reducing landscape permeability between neighbouring wildlife areas. Cheetahs were also less likely to stop in areas where livestock numbers were high, but more likely to stop in areas that were frequently used by livestock. The latter could reflect that cheetahs are attracted to livestock however, cheetahs in the study area rarely predated on livestock. It is therefore more likely that areas that are frequently used by livestock attract wild herbivores, which in turn could influence cheetah space use. We did not find any effects of people and livestock on cheetahs? speed and turn angles which might be related to the resolution of the data. We found that cheetahs are sensitive to human pressures and we believe that they could be an indicator species for other large carnivores facing similar challenges. We suggest that further research is needed to determine the levels of anthropogenic pressures needed to maintain ecological integrity, especially inside wildlife areas.
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Leighty, K. A., & Fragaszy, D. M. (2003). Primates in cyberspace: using interactive computer tasks to study perception and action in nonhuman animals. Anim. Cogn., 6(3), 137–139.
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White, A. M., Swaisgood, R. R., & Czekala, N. (2007). Ranging patterns in white rhinoceros, Ceratotherium simum simum: implications for mating strategies. Appl. Anim. Behav. Sci., 74(2), 349–356.
Abstract: How animals use space has important consequences for feeding ecology, social organization, mating strategies and conservation management. In white rhinoceros, female home ranges are much larger than male territories, suggesting that movement patterns are influenced by factors other than resource distribution. In this study we placed radiotransmitters on 15 female white rhinoceros, recording 1758 locations and collecting behavioural data during 1671 observation sessions, making this the largest data set of its kind in this species. We investigated how habitat variables and male territories influenced female movement and reproductive behaviour. Female home ranges were approximately 20 km2 and core areas were 5 km2, with male territories roughly the same size as female core areas. Female range size did not vary with season, but the pattern of space use did vary. Females used grassland habitat preferentially, utilizing these areas significantly more than expected based on availability. Findings relevant to the mating strategy include: (1) the amount of grassland in a male's territory predicted female use of the territory; (2) the time that a female spent in a male's territory was a significant predictor of reproductive activity with the male, indicating that females probably mate with the most familiar male; and (3) the temporal pattern of female space use suggests that females did not increase mate sampling behaviour nor did they become more choosy about which males they visited when reproductively active. These findings suggest that males may maximize reproductive success by defending areas containing more grassland habitat.
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Stahl, F., & Dorner, G. (1982). Responses of salivary cortisol levels to stress-situations. Endokrinologie, 80(2), 158–162.
Abstract: A procedure is described for determining salivary cortisol levels by a competitive protein-binding assay using horse transcortin. The collection of saliva was performed by means of filter paper-strips. Filter paper samples are more than 5 days stable after air-drying. In this form, the samples could be stored without refrigerator or deep-freezer and, if necessary, sent by post to the laboratory without any special precaution. Stressful situation of either painful or anxious origin were associated with an adequate increase of salivary cortisol levels. The increases were 157 to 230% of the initial or normal values dependent on the kind of stress. The mean values in 4 cases of Cushing's syndrome were 380% and 1 hour after 25 I.U. ACTH 690% higher than those in normal persons. In normal persons, a well-defined circadian rhythm has been observed.
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Amant, R. S., & Horton, T. E. (2008). Revisiting the definition of animal tool use. Anim. Behav., 75(4), 1199–1208.
Abstract: Benjamin Beck's definition of tool use has served the field of animal cognition well for over 25 years (Beck 1980, Animal Tool Behavior: the Use and Manufacture of Tools, New York, Garland STPM). This article proposes a new, more explanatory definition that accounts for tool use in terms of two complementary subcategories of behaviours: behaviours aimed at altering a target object by mechanical means and behaviours that mediate the flow of information between the tool user and the environment or other organisms in the environment. The conceptual foundation and implications of the new definition are contrasted with those of existing definitions, particularly Beck's. The new definition is informally evaluated with respect to a set of scenarios that highlights differences from Beck's definition as well as those of others in the literature.
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Boden, L. A., Anderson, G. A., Charles, J. A., Morgan, K. L., Morton, J. M., Parkin, T. D. H., et al. (2006). Risk of fatality and causes of death of Thoroughbred horses associated with racing in Victoria, Australia: 1989-2004. Equine Vet J, 38(4), 312–318.
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.
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Linklater, W. L., Cameron, E. Z., Stafford, K. J., & Veltman, C. J. (2000). Social and spatial structure and range use by Kaimanawa wild horses (Equus caballus: Equidae). New Zealand J. Ecol., 24(2), 139–152.
Abstract: We measured horse density, social structure, habitat use, home ranges and altitudinal micro-climates in the south-western Kaimanawa ranges east of Waiouru, New Zealand. Horse density in the Auahitotara ecological sector averaged 3.6 horses.km-2 and ranged from 0.9 to 5.2 horses.km-2 within different zones. The population's social structure was like that of other feral horse populations with an even adult sex ratio, year round breeding groups (bands) with stable adult membership consisting of 1 to 11 mares, 1 to 4 stallions, and their predispersal offspring, and bachelor groups with unstable membership. Bands and bachelor males were loyal to undefended home ranges with central core use areas. Band home range sizes varied positively with adult band size. Home ranges overlapped entirely with other home ranges. Horses were more likely to occupy north facing aspects, short tussock vegetation and flush zones and avoid high altitudes, southern aspects, steeper slopes, bare ground and forest remnants. Horses were more likely to be on north facing aspects, steeper slopes, in exotic and red tussock grasslands and flush zones during winter and at lower altitudes and on gentler slopes in spring and summer. Seasonal shifts by bands to river basin and stream valley floors in spring and higher altitudes in autumn and winter are attributed to the beginning of foaling and mating in spring and formation of frost inversion layers in winter. Given horse habitat selectivity and the presence of other ungulate herbivores, results from present exclosures are likely to exaggerate the size of horse impacts on range vegetation. Proposals to manage the population by relocation and confinement are likely to modify current social structure and range use behaviour and may lead to the need for more intensive management in the longer term.
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Guttridge, T. L., Dijk, S., Stamhuis, E. J., Krause, J., Gruber, S. H., & Brown, C. (2013). Social learning in juvenile lemon sharks, Negaprion brevirostris. Animal Cognition, 16(1), 55–64.
Abstract: Social learning is taxonomically widespread and can provide distinct behavioural advantages, such as in finding food or avoiding predators more efficiently. Although extensively studied in bony fishes, no such empirical evidence exists for cartilaginous fishes. Our aim in this study was to experimentally investigate the social learning capabilities of juvenile lemon sharks, Negaprion brevirostris. We designed a novel food task, where sharks were required to enter a start zone and subsequently make physical contact with a target in order to receive a food reward. Naive sharks were then able to interact with and observe (a) pre-trained sharks, that is, ‘demonstrators’, or (b) sharks with no previous experience, that is, ‘sham demonstrators’. On completion, observer sharks were then isolated and tested individually in a similar task. During the exposure phase observers paired with ‘demonstrator’ sharks performed a greater number of task-related behaviours and made significantly more transitions from the start zone to the target, than observers paired with ‘sham demonstrators’. When tested in isolation, observers previously paired with ‘demonstrator’ sharks completed a greater number of trials and made contact with the target significantly more often than observers previously paired with ‘sham demonstrators’. Such experience also tended to result in faster overall task performance. These results indicate that juvenile lemon sharks, like numerous other animals, are capable of using socially derived information to learn about novel features in their environment. The results likely have important implications for behavioural processes, ecotourism and fisheries.
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