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Mejdell, C. M., Buvik, T., Jørgensen, G. H. M., & Bøe, K. E. (2016). Horses can learn to use symbols to communicate their preferences. Appl. Anim. Behav. Sci., 184, 66–73.
Abstract: Abstract This paper describes a method in which horses learn to communicate by touching different neutral visual symbols, in order to tell the handler whether they want to have a blanket on or not. Horses were trained for 10–15 min per day, following a training program comprising ten steps in a strategic order. Reward based operant conditioning was used to teach horses to approach and touch a board, and to understand the meaning of three different symbols. Heat and cold challenges were performed to help learning and to check level of understanding. At certain stages, a learning criterion of correct responses for 8–14 successive trials had to be achieved before proceeding. After introducing the free choice situation, on average at training day 11, the horse could choose between a “no change” symbol and the symbol for either “blanket on” or “blanket off” depending on whether the horse already wore a blanket or not. A cut off point for performance or non-performance was set to day 14, and 23/23 horses successfully learned the task within this limit. Horses of warm-blood type needed fewer training days to reach criterion than cold-bloods (P < 0.05). Horses were then tested under differing weather conditions. Results show that choices made, i.e. the symbol touched, was not random but dependent on weather. Horses chose to stay without a blanket in nice weather, and they chose to have a blanket on when the weather was wet, windy and cold (χ2 = 36.67, P < 0.005). This indicates that horses both had an understanding of the consequence of their choice on own thermal comfort, and that they successfully had learned to communicate their preference by using the symbols. The method represents a novel tool for studying preferences in horses.
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Mejdell, C. M., Buvik, T., Jørgensen, G. H. M., & Bøe, K. E. (2016). Horses can learn to use symbols to communicate their preferences. Appl. Anim. Behav. Sci., 184, 66–73.
Abstract: This paper describes a method in which horses learn to communicate by touching different neutral visual symbols, in order to tell the handler whether they want to have a blanket on or not. Horses were trained for 10-15min per day, following a training program comprising ten steps in a strategic order. Reward based operant conditioning was used to teach horses to approach and touch a board, and to understand the meaning of three different symbols. Heat and cold challenges were performed to help learning and to check level of understanding. At certain stages, a learning criterion of correct responses for 8-14 successive trials had to be achieved before proceeding. After introducing the free choice situation, on average at training day 11, the horse could choose between a “no change” symbol and the symbol for either “blanket on” or “blanket off” depending on whether the horse already wore a blanket or not. A cut off point for performance or non-performance was set to day 14, and 23/23 horses successfully learned the task within this limit. Horses of warm-blood type needed fewer training days to reach criterion than cold-bloods (P<0.05). Horses were then tested under differing weather conditions. Results show that choices made, i.e. the symbol touched, was not random but dependent on weather. Horses chose to stay without a blanket in nice weather, and they chose to have a blanket on when the weather was wet, windy and cold (χ2=36.67, P<0.005). This indicates that horses both had an understanding of the consequence of their choice on own thermal comfort, and that they successfully had learned to communicate their preference by using the symbols. The method represents a novel tool for studying preferences in horses.
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Mejdell, C. M., Buvik, T., Jørgensen, G. H. M., & Bøe, K. E. (2016). Horses can learn to use symbols to communicate their preferences. Appl. Anim. Behav. Sci., 184, 66–73.
Abstract: This paper describes a method in which horses learn to communicate by touching different neutral visual symbols, in order to tell the handler whether they want to have a blanket on or not. Horses were trained for 10-15min per day, following a training program comprising ten steps in a strategic order. Reward based operant conditioning was used to teach horses to approach and touch a board, and to understand the meaning of three different symbols. Heat and cold challenges were performed to help learning and to check level of understanding. At certain stages, a learning criterion of correct responses for 8-14 successive trials had to be achieved before proceeding. After introducing the free choice situation, on average at training day 11, the horse could choose between a “no change” symbol and the symbol for either “blanket on” or “blanket off” depending on whether the horse already wore a blanket or not. A cut off point for performance or non-performance was set to day 14, and 23/23 horses successfully learned the task within this limit. Horses of warm-blood type needed fewer training days to reach criterion than cold-bloods (P<0.05). Horses were then tested under differing weather conditions. Results show that choices made, i.e. the symbol touched, was not random but dependent on weather. Horses chose to stay without a blanket in nice weather, and they chose to have a blanket on when the weather was wet, windy and cold (χ2=36.67, P<0.005). This indicates that horses both had an understanding of the consequence of their choice on own thermal comfort, and that they successfully had learned to communicate their preference by using the symbols. The method represents a novel tool for studying preferences in horses.
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Heleski, C. R., McGreevy, P. D., Kaiser, L. J., Lavagnino, M., Tans, E., Bello, N., et al. (2009). Effects on behaviour and rein tension on horses ridden with or without martingales and rein inserts. The Veterinary Journal, 181(1), 56–62.
Abstract: Unsteady hand position can cause discomfort to the horse, potentially leading to conflict behaviours (CB) such as head tossing or tail lashing. Some instructors feel that martingales or elastic rein inserts can reduce discomfort caused by inexperienced and unsteady hands. Others consider these devices to be inappropriate [`]crutches'. Four horses and nine riders were tested under three conditions in random order: plain reins, adjustable training martingales (TM), and elasticised rein inserts (RI). Rein-tension data (7Â s) and behavioural data (30Â s) were collected in each direction. Rein-tension data were collected via strain-gauge transducers. Behavioural data were assessed using an ethogram of defined behaviours. No differences in the number of CB were observed. Mean rein tension for TM was higher than that of RI or controls. Relative to the withers, the head was lower for horses ridden with martingales. Carefully fitted martingales may have a place in riding schools that teach novices.
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Koistinen, T., Korhonen, H. T., Hämäläinen, E., & Mononen, J. (2016). Blue foxes' (Vulpes lagopus) motivation to gain access and interact with various resources. Appl. Anim. Behav. Sci., 176, 105–111.
Abstract: We analysed the willingness of blue foxes (Vulpes lagopus) to work for and utilise five resources: a platform, wooden block, sand floor, nest box and empty space. Ten juvenile blue fox males were housed singly in apparatus consisting of three cages connected with one-way doors through the walls in between the cages and subjected to work for each of the five resources, one at a time. The resource was placed in one of the outermost cages of the apparatus. Force needed to open the door leading to the resource cage was increased daily by 0.25 or 0.5kg. The number of daily entries, visit durations and interaction with the resource were recorded on workloads of 0, 0.5, 1.5, 2.5, 3.5, 5, 6.5, and 8kg of extra weight. The latency to start interacting with the resource after entering the resource cage was measured on a workload of 3.5kg. The mean number of daily entries in the resource and the other outermost, i.e. control cage varied from 7 to 28 and from 17 to 44, respectively. The increasing workload decreased the number of entries in the resource cage, increased those in the control cage (Linear Mixed Model: F1,638=79.5, P<0.001) and lengthened the visit durations in both cages (F1,642=7.2, P<0.01). The foxes made most (F4,643=9.0, P<0.001) and shortest (F4,641=2.8, P<0.05) visits to the outermost cages when the available resource was either a platform or empty space. The visit durations were longest when the available resource was a nest box. The foxes interacted regularly with the wooden block, but five foxes were not observed interacting with the platform. The nest box was utilised approximately 50% of the time spent in the resource cage, while the platform was utilised only 1-6% and wooden block 2-17% of the time. The mean latency to start interacting with the resource after entering the resource cage was shortest for the sand floor (8s) and longest for the platform (113s, F3,335=26.3, P<0.001). The results show that the foxes re-scheduled their activities on increasing workloads in the apparatus. Based on the number of entries and visit durations, blue foxes valued the wooden block, nest box and sand floor more than the platform or an empty cage. After entering the resource cage, the foxes started interacting fastest with the sand floor, showing high motivation to interact. After entering the resource cage, the foxes make use of the roof of the nest box more urgently than the interior of the nest box. Long bouts in the cage with nest box indicate resting behaviour.
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Geutjens, C. A., Clayton, H. M., & Kaiser, L. J. (2008). Forces and pressures beneath the saddle during mounting from the ground and from a raised mounting platform. The Veterinary Journal, 175(3), 332–337.
Abstract: The objective was to use an electronic pressure mat to measure and compare forces and pressures of the saddle on a horse's back when riders mounted from the ground and with the aid of a mounting platform. Ten riders mounted a horse three times each from the ground and from a 35 cm high mounting platform in random order. Total force (summation of forces over all 256 sensors) was measured and compared at specific points on the force-time curve. Total force was usually highest as the rider's right leg was swinging upwards and was correlated with rider mass. When normalized to rider mass, total force and peak pressure were significantly higher when mounting from the ground than from a raised platform (P < 0.05). The area of highest pressure was on the right side of the withers in 97% of mounting efforts, confirming the importance of the withers in stabilizing the saddle during mounting.
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Meschan, E. M., Peham, C., Schobesberger, H., & Licka, T. F. (2007). The influence of the width of the saddle tree on the forces and the pressure distribution under the saddle. The Veterinary Journal, 173(3), 578–584.
Abstract: As there is no statistical evidence that saddle fit influences the load exerted on a horse's back this study was performed to assess the hypothesis that the width of the tree significantly alters the pressure distribution on the back beneath the saddle. Nineteen sound horses were ridden at walk and trot on a treadmill with three saddles differing only in tree width. Kinetic data were recorded by a sensor mat. A minimum of 14 motion cycles were used in each trial. The saddles were classified into four groups depending on fit. For each horse, the saddle with the lowest overall force (LOF) was determined. Saddles were classified as “too-narrow” if they were one size (2 cm) narrower than the LOF saddle, and “too-wide” if they were one size (2 cm) wider than the LOF saddle. Saddles two sizes wider than LOF saddles were classified as “very-wide”. In the group of narrow saddles, the pressure in the caudal third (walk 0.63 N/cm2 +/- 0.10; trot 1.08 N/cm2 +/- 0.26) was significantly higher compared to the LOF saddles (walk 0.50 N/cm2 +/- 0.09; trot 0.86 N/cm2 +/- 0.28). In the middle transversal third, the pressure of the wide saddles (walk 0.73 N/cm2 +/- 0.06; trot 1.52 N/cm2 +/- 0.19) and very-wide saddles (walk 0.77 N/cm2 +/- 0.06; trot 1.57 N/cm2 +/- 0.19) was significantly higher compared to LOF saddles (walk 0.65 N/cm2 +/- 0.10/ 0.63 N/cm2 +/- 0.11; trot 1.33 N/cm2 +/- 0.22/1.27 N/cm2 +/- 0.20). This study demonstrates that the load under poorly fitting saddles is distributed over a smaller area than under properly fitting saddles, leading to potentially harmful pressures peaks.
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Hieshima, K., Kawasaki, Y., Hanamoto, H., Nakayama, T., Nagakubo, D., Kanamaru, A., et al. (2004). CC Chemokine Ligands 25 and 28 Play Essential Roles in Intestinal Extravasation of IgA Antibody-Secreting Cells. The Journal of Immunology, 173(6), 3668–3675.
Abstract: CCL25 (also known as thymus-expressed chemokine) and CCL28 (also known as mucosae-associated epithelial chemokine) play important roles in mucosal immunity by recruiting IgA Ab-secreting cells (ASCs) into mucosal lamina propria. However, their exact roles in vivo still remain to be defined. In this study, we first demonstrated in mice that IgA ASCs in small intestine expressed CCR9, CCR10, and CXCR4 on the cell surface and migrated to their respective ligands CCL25, CCL28, and CXCL12 (also known as stromal cell-derived factor 1), whereas IgA ASCs in colon mainly expressed CCR10 and CXCR4 and migrated to CCL28 and CXCL12. Reciprocally, the epithelial cells of small intestine were immunologically positive for CCL25 and CCL28, whereas those of colon were positive for CCL28 and CXCL12. Furthermore, the venular endothelial cells in small intestine were positive for CCL25 and CCL28, whereas those in colon were positive for CCL28, suggesting their direct roles in extravasation of IgA ASCs. Consistently, in mice orally immunized with cholera toxin (CT), anti-CCL25 suppressed homing of CT-specific IgA ASCs into small intestine, whereas anti-CCL28 suppressed homing of CT-specific IgA ASCs into both small intestine and colon. Reciprocally, CT-specific ASCs and IgA titers in the blood were increased in mice treated with anti-CCL25 or anti-CCL28. Anti-CXCL12 had no such effects. Finally, both CCL25 and CCL28 were capable of enhancing α4 integrin-dependent adhesion of IgA ASCs to mucosal addressin cell adhesion molecule-1 and VCAM-1. Collectively, CCL25 and CCL28 play essential roles in intestinal homing of IgA ASCs primarily by mediating their extravasation into intestinal lamina propria.
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Stock, K. F., Hamann, H., & Distl, O. (2006). Factors associated with the prevalence of osseous fragments in the limb joints of Hanoverian Warmblood horses. Vet J, 171(1), 147–156.
Abstract: Factors associated with the prevalence of osseous fragments (OF) in fetlock and hock joints were investigated in a population of young Hanoverian Warmblood horses selected for sale at auction from 1991 to 1998. The study was based on results of a standardized radiological examination of 3127 horses. The prevalences of OF in the two joints were significantly dependent on the date, type and quality of the auction, the region of origin and on the anticipated suitability of the horses for dressage and/or show-jumping. The probability of finding OF increased with wither-height. Furthermore, there was a significant association of the individual sire with the prevalence of OF in both fetlock and hock joints, and of the maternal grandsire with the prevalence of OF in the hock joints. Consequently, both non-genetic and genetic parameters should be taken into account in order to reduce the prevalence of OF in young Warmblood riding horses.
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Uehara, T., Yokomizo, H., & Iwasa, Y. (2005). Mate-choice copying as Bayesian decision making. Am Nat, 165(3), 403–410.
Abstract: Mate-choice copying by females has been reported in fishes (e.g., guppies) and lekking birds. Presumably, females assess males' quality using both information from direct observation of males and information acquired by observing other females' choices. Here, we study mathematically the conditions under which mate-choice copying is advantageous on the basis of Bayesian decision theory. A female may observe the mate choice of another female, called the model female, who has performed an optimal choice based on her own judgment. The conditions required for the focal female to choose the same mate as that chosen by the model female should depend on the male's appearance to her, the reliability of her own judgment of male quality, and the reliability of the model females. When three or more females are involved, the optimal mate choice critically depends on whether multiple model females make decisions independently or they themselves copy the choices of others. If two equally reliable females choose different males, the choice of the second female, made knowing the choice of the first, should have a stronger effect on the choice of the third (focal) female. This “last-choice precedence” should be tested experimentally.
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