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Author Dougherty, D.M.; Lewis, P. doi  openurl
  Title Generalization of a tactile stimulus in horses Type Journal Article
  Year 1993 Publication Journal of the Experimental Analysis of Behavior Abbreviated Journal J Exp Anal Behav  
  Volume 59 Issue 3 Pages 521-528  
  Keywords Animals; Behavior, Animal; Female; *Horses; Male; Reinforcement (Psychology); *Touch  
  Abstract Using horses, we investigated the control of operant behavior by a tactile stimulus (the training stimulus) and the generalization of behavior to six other similar test stimuli. In a stall, the experimenters mounted a response panel in the doorway. Located on this panel were a response lever and a grain dispenser. The experimenters secured a tactile-stimulus belt to the horse's back. The stimulus belt was constructed by mounting seven solenoids along a piece of burlap in a manner that allowed each to provide the delivery of a tactile stimulus, a repetitive light tapping, at different locations (spaced 10.0 cm apart) along the horse's back. Two preliminary steps were necessary before generalization testing: training a measurable response (lip pressing) and training on several reinforcement schedules in the presence of a training stimulus (tapping by one of the solenoids). We then gave each horse two generalization test sessions. Results indicated that the horses' behavior was effectively controlled by the training stimulus. Horses made the greatest number of responses to the training stimulus, and the tendency to respond to the other test stimuli diminished as the stimuli became farther away from the training stimulus. These findings are discussed in the context of behavioral principles and their relevance to the training of horses.  
  Address Human Behavioral Pharmacology Laboratory, University of Texas Health Science Center, Houston 77030  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-5002 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:8315368 Approved no  
  Call Number Equine Behaviour @ team @ Serial 3571  
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Author Dougherty, D.M.; Lewis, P. doi  openurl
  Title Stimulus generalization, discrimination learning, and peak shift in horses Type Journal Article
  Year 1991 Publication Journal of the experimental analysis of behavior Abbreviated Journal J Exp Anal Behav  
  Volume 56 Issue 1 Pages 97-104  
  Keywords Animals; *Appetitive Behavior; Attention; *Conditioning, Operant; *Discrimination Learning; Female; *Generalization, Stimulus; Horses/*psychology; Male; *Pattern Recognition, Visual; Size Perception  
  Abstract Using horses, we investigated three aspects of the stimulus control of lever-pressing behavior: stimulus generalization, discrimination learning, and peak shift. Nine solid black circles, ranging in size from 0.5 in. to 4.5 in. (1.3 cm to 11.4 cm) served as stimuli. Each horse was shaped, using successive approximations, to press a rat lever with its lip in the presence of a positive stimulus, the 2.5-in. (6.4-cm) circle. Shaping proceeded quickly and was comparable to that of other laboratory organisms. After responding was maintained on a variable-interval 30-s schedule, stimulus generalization gradients were collected from 2 horses prior to discrimination training. During discrimination training, grain followed lever presses in the presence of a positive stimulus (a 2.5-in circle) and never followed lever presses in the presence of a negative stimulus (a 1.5-in. [3.8-cm] circle). Three horses met a criterion of zero responses to the negative stimulus in fewer than 15 sessions. Horses given stimulus generalization testing prior to discrimination training produced symmetrical gradients; horses given discrimination training prior to generalization testing produced asymmetrical gradients. The peak of these gradients shifted away from the negative stimulus. These results are consistent with discrimination, stimulus generalization, and peak-shift phenomena observed in other organisms.  
  Address Department of Psychology, Ohio University, Athens 45701  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-5002 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:1940765 Approved no  
  Call Number Serial 1764  
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Author Robert, N.; Walzer, C.; Ruegg, S.R.; Kaczensky, P.; Ganbaatar, O.; Stauffer, C. doi  openurl
  Title Pathologic findings in reintroduced Przewalski's horses (Equus caballus przewalskii) in southwestern Mongolia Type Journal Article
  Year 2005 Publication Journal of zoo and Wildlife Medicine : Official Publication of the American Association of Zoo Veterinarians Abbreviated Journal J Zoo Wildl Med  
  Volume 36 Issue 2 Pages 273-285  
  Keywords Animals; Babesiosis/epidemiology/pathology/*veterinary; Cause of Death; Conservation of Natural Resources; Disease Susceptibility/veterinary; Environment; Female; Food Chain; Horse Diseases/*epidemiology/pathology; Horses; Male; Mongolia/epidemiology; Streptococcal Infections/epidemiology/pathology/*veterinary; *Streptococcus equi; Theileriasis/*epidemiology/pathology; Weather  
  Abstract The Przewalski's horse (Equus caballus przewalskii) was extinct in the wild by the mid 1960s. The species has survived because of captive breeding only. The Takhin Tal reintroduction project is run by the International Takhi Group; it is one of two projects reintroducing horses to the wild in Mongolia. In 1997 the first harem group was released. The first foals were successfully raised in the wild in 1999. Currently, 63 Przewalski's horses live in Takhin Tal. Little information exists on causes of mortality before the implementation of a disease-monitoring program in 1998. Since 1999, all dead horses recovered (n = 28) have been examined and samples collected and submitted for further investigation. Equine piroplasmosis, a tick-transmitted disease caused by Babesia caballi or Theileria equi, is endemic in Takhin Tal and was identified as the cause of death of four stallions and one stillborn foal. In December 2000, wolf predation was implicated in the loss of several Przewalski's horses. However, thorough clinical, pathologic, and bacteriologic investigations performed on dead and surviving horses of this group revealed lesions compatible with strangles. The extreme Mongolian winter of 2000-2001 is thought to have most probably weakened the horses, making them more susceptible to opportunistic infection and subsequent wolf predation. Other occasional causes of death since 1999 were trauma, exhaustion, wasting, urolithiasis, pneumonia, abortion, and stillbirth. The pathologic examination of the Przewalski's horses did not result in a definitive diagnosis in each case. Several disease factors were found to be important in the initial phase of the reintroduction, which could potentially jeopardize the establishment of a self-sustaining population.  
  Address Center for Fish and Wildlife Health, Institute of Animal Pathology, University of Berne, Langgass-Strasse 122, CH-3001 Berne, Switzerland  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1042-7260 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:17323569 Approved no  
  Call Number Serial 2023  
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Author Balakrishnan, G.; Hu, Y.; Spiro, T.G. doi  openurl
  Title Temperature-jump apparatus with Raman detection based on a solid-state tunable (1.80-2.05 microm) kHz optical parametric oscillator laser Type Journal Article
  Year 2006 Publication Applied Spectroscopy Abbreviated Journal Appl Spectrosc  
  Volume 60 Issue 4 Pages 347-351  
  Keywords Animals; Cytochromes c/analysis; Horses; Lasers; Myoglobin/metabolism; Spectrum Analysis, Raman/*instrumentation/*methods; *Temperature  
  Abstract The operating characteristics of a pulsed (10 ns) tunable near-infrared (NIR) laser source are described for temperature-jump (T-jump) applications. A Q-switched Nd:YLF laser (approximately 10 ns pulses) with a 1 kHz repetition rate is used to pump a potassium titanyl arsenate (KTA) crystal-based optical parametric oscillator (OPO), producing approximately 1 mJ NIR pulses that are tunable (1.80-2.05 microm) across the 1.9 microm vibrational overtone band of water. This T-jump source has been coupled to a deep ultraviolet (UV) probe laser for Raman studies of protein dynamics. T-jumps of up to 30 degrees C, as measured via the O-H stretching Raman band of water, are readily achieved. Application to cytochrome c unfolding is demonstrated.  
  Address Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-7028 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16613628 Approved no  
  Call Number Equine Behaviour @ team @ Serial 3764  
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Author Arnold, W.; Ruf, T.; Kuntz, R. doi  openurl
  Title Seasonal adjustment of energy budget in a large wild mammal, the Przewalski horse (Equus ferus przewalskii) II. Energy expenditure Type Journal Article
  Year 2006 Publication The Journal of experimental biology Abbreviated Journal J Exp Biol  
  Volume 209 Issue Pt 22 Pages 4566-4573  
  Keywords Animals; Animals, Wild/*physiology; Body Temperature; Body Temperature Regulation; Eating; *Energy Metabolism; Female; Heart Rate; Horses/*physiology; Male; Motor Activity; Pregnancy; Reproduction; *Seasons  
  Abstract Many large mammals show pronounced seasonal fluctuations of metabolic rate (MR). It has been argued, based on studies in ruminants, that this variation merely results from different levels of locomotor activity (LA), and heat increment of feeding (HI). However, a recent study in red deer (Cervus elaphus) identified a previously unknown mechanism in ungulates--nocturnal hypometabolism--that contributed significantly to reduced energy expenditure, mainly during late winter. The relative contribution of these different mechanisms to seasonal adjustments of MR is still unknown, however. Therefore, in the study presented here we quantified for the first time the independent contribution of thermoregulation, LA and HI to heart rate (f(H)) as a measure of MR in a free-roaming large ungulate, the Przewalski horse or Takhi (Equus ferus przewalskii Poljakow). f(H) varied periodically throughout the year with a twofold increase from a mean of 44 beats min(-1) during December and January to a spring peak of 89 beats min(-1) at the beginning of May. LA increased from 23% per day during December and January to a mean level of 53% per day during May, and declined again thereafter. Daily mean subcutaneous body temperature (T(s)) declined continuously during winter and reached a nadir at the beginning of April (annual range was 5.8 degrees C), well after the annual low of air temperature and LA. Lower T(s) during winter contributed considerably to the reduction in f(H). In addition to thermoregulation, f(H) was affected by reproduction, LA, HI and unexplained seasonal variation, presumably reflecting to some degree changes in organ mass. The observed phase relations of seasonal changes indicate that energy expenditure was not a consequence of energy uptake but is under endogenous control, preparing the organism well in advance of seasonal energetic demands.  
  Address Research Institute of Wildlife Ecology, University of Veterinary Medicine, Vienna, Savoyenstrasse 1, 1160 Vienna, Austria. walter.arnold@vu-wien.ac.at  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-0949 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:17079726 Approved no  
  Call Number Serial 1782  
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Author Bobbert, M.F.; Santamaria, S. doi  openurl
  Title Contribution of the forelimbs and hindlimbs of the horse to mechanical energy changes in jumping Type Journal Article
  Year 2005 Publication The Journal of Experimental Biology Abbreviated Journal J Exp Biol  
  Volume 208 Issue 2 Pages 249-260  
  Keywords Animals; Biomechanics; Forelimb/*physiology; Hindlimb/*physiology; Horses/*physiology; Locomotion/*physiology; Muscle, Skeletal/*physiology; Time Factors  
  Abstract The purpose of the present study was to gain more insight into the contribution of the forelimbs and hindlimbs of the horse to energy changes during the push-off for a jump. For this purpose, we collected kinematic data at 240 Hz from 23 5-year-old Warmbloods (average mass: 595 kg) performing free jumps over a 1.15 m high fence. From these data, we calculated the changes in mechanical energy and the changes in limb length and joint angles. The force carried by the forelimbs and the amount of energy stored was estimated from the distance between elbow and hoof, assuming that this part of the leg behaved as a linear spring. During the forelimb push, the total energy first decreased by 3.2 J kg(-1) and then increased again by 4.2 J kg(-1) to the end of the forelimb push. At the end of the forelimb push, the kinetic energy due to horizontal velocity of the centre of mass was 1.6 J kg(-1) less than at the start, while the effective energy (energy contributing to jump height) was 2.3 J kg(-1) greater. It was investigated to what extent these changes could involve passive spring-like behaviour of the forelimbs. The amount of energy stored and re-utilized in the distal tendons during the forelimb push was estimated to be on average 0.4 J kg(-1) in the trailing forelimb and 0.23 J kg(-1) in the leading forelimb. This means that a considerable amount of energy was first dissipated and subsequently regenerated by muscles, with triceps brachii probably being the most important contributor. During the hindlimb push, the muscles of the leg were primarily producing energy. The total increase in energy was 2.5 J kg(-1) and the peak power output amounted to 71 W kg(-1).  
  Address Institute for Fundamental and Clinical Human Movement Sciences, Vrije Universiteit, van der Boechorstraat 9, NL-1081 BT Amsterdam, The Netherlands. MFBobbert@fbw.vu.nl  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-0949 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15634844 Approved no  
  Call Number Serial 1895  
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Author Carroll, J.; Murphy, C.J.; Neitz, M.; Hoeve, J.N.; Neitz, J. doi  openurl
  Title Photopigment basis for dichromatic color vision in the horse Type Journal Article
  Year 2001 Publication Journal of Vision Abbreviated Journal J Vis  
  Volume 1 Issue 2 Pages 80-87  
  Keywords Adaptation, Physiological; Animals; Color Perception/*physiology; Cones (Retina)/chemistry/*physiology; Electroretinography; Horses/*physiology; Photic Stimulation; Phototransduction/physiology; Retinal Pigments/analysis/*physiology; Visual Perception/physiology  
  Abstract Horses, like other ungulates, are active in the day, at dusk, dawn, and night; and, they have eyes designed to have both high sensitivity for vision in dim light and good visual acuity under higher light levels (Walls, 1942). Typically, daytime activity is associated with the presence of multiple cone classes and color-vision capacity (Jacobs, 1993). Previous studies in other ungulates, such as pigs, goats, cows, sheep and deer, have shown that they have two spectrally different cone types, and hence, at least the photopigment basis for dichromatic color vision (Neitz & Jacobs, 1989; Jacobs, Deegan II, Neitz, Murphy, Miller, & Marchinton, 1994; Jacobs, Deegan II, & Neitz, 1998). Here, electroretinogram flicker photometry was used to measure the spectral sensitivities of the cones in the domestic horse (Equus caballus). Two distinct spectral mechanisms were identified and are consistent with the presence of a short-wavelength-sensitive (S) and a middle-to-long-wavelength-sensitive (M/L) cone. The spectral sensitivity of the S cone was estimated to have a peak of 428 nm, while the M/L cone had a peak of 539 nm. These two cone types would provide the basis for dichromatic color vision consistent with recent results from behavioral testing of horses (Macuda & Timney, 1999; Macuda & Timney, 2000; Timney & Macuda, 2001). The spectral peak of the M/L cone photopigment measured here, in vivo, is similar to that obtained when the gene was sequenced, cloned, and expressed in vitro (Yokoyama & Radlwimmer, 1999). Of the ungulates that have been studied to date, all have the photopigment basis for dichromatic color vision; however, they differ considerably from one another in the spectral tuning of their cone pigments. These differences may represent adaptations to the different visual requirements of different species.  
  Address Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee, WI, USA  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1534-7362 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:12678603 Approved no  
  Call Number Equine Behaviour @ team @ Serial 4060  
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Author Giles, N.; Tupper, J. doi  openurl
  Title Equine interspecies aggression Type
  Year 2006 Publication The Veterinary record Abbreviated Journal Vet. Rec.  
  Volume 159 Issue 22 Pages 756  
  Keywords Aggression/*physiology; Animals; Horses/*physiology; Sheep/*physiology; Social Dominance  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0042-4900 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:17127768 Approved no  
  Call Number Serial 1779  
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Author Harman, A.M.; Moore, S.; Hoskins, R.; Keller, P. doi  openurl
  Title Horse vision and an explanation for the visual behaviour originally explained by the 'ramp retina' Type Journal Article
  Year 1999 Publication Equine veterinary journal Abbreviated Journal Equine Vet J  
  Volume 31 Issue 5 Pages 384-390  
  Keywords Animals; Behavior, Animal; Cell Count; Eye/*anatomy & histology; Ganglia, Sensory/cytology; Horses/*physiology; Refractive Errors/veterinary; Retina/cytology/*physiology; Vision/*physiology; Visual Acuity; Visual Fields  
  Abstract Here we provide confirmation that the 'ramp retina' of the horse, once thought to result in head rotating visual behaviour, does not exist. We found a 9% variation in axial length of the eye between the streak region and the dorsal periphery. However, the difference was in the opposite direction to that proposed for the 'ramp retina'. Furthermore, acuity in the narrow, intense visual streak in the inferior retina is 16.5 cycles per degree compared with 2.7 cycles per degree in the periphery. Therefore, it is improbable that the horse rotates its head to focus onto the peripheral retina. Rather, the horse rotates the nose up high to observe distant objects because binocular overlap is oriented down the nose, with a blind area directly in front of the forehead.  
  Address Department of Psychology, University of Western Australia, Nedlands, Australia  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0425-1644 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:10505953 Approved no  
  Call Number refbase @ user @ Serial 836  
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Author Hawkes, J.; Hedges, M.; Daniluk, P.; Hintz, H.F.; Schryver, H.F. doi  openurl
  Title Feed preferences of ponies Type Journal Article
  Year 1985 Publication Equine Veterinary Journal Abbreviated Journal Equine Vet J  
  Volume 17 Issue 1 Pages 20-22  
  Keywords *Animal Feed; Animals; Feeding Behavior/physiology; Female; *Food Preferences; Horses/*physiology; Male  
  Abstract Preference trials were conducted with mature ponies. In Trial 1, oats were compared with oats plus sucrose. Four of six pony geldings selected oats plus sucrose, but one pony demonstrated a dislike for sucrose and one selected from the bucket on the right side regardless of content. Oats, maize, barley, rye and wheat were compared in Trial 2 using six mature pony mares. Oats were the preferred grain, with maize and barley ranking second and third respectively. Wheat and rye were the least preferred. Even though the ponies demonstrated preference, the total intake at a given meal was not greatly depressed when only the less palatable grains were fed. In Trial 3, pony mares selected a diet containing 20 per cent dried distillers' grain and 80 per cent of a basal mixed diet of maize, oats, wheat bran, soybean meal, limestone and molasses over 100 per cent basal mixed diet, but selected the basal diet over diets containing 20 per cent blood meal, beet pulp or meat and bone meal and 80 per cent basal diet. They did not differentiate against diets containing 20 per cent alfalfa meal or 10 or 5 per cent meat and bone meal when the diets were compared to the basal mixed diet.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0425-1644 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:3979369 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2298  
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