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Author |
Jansen, W.L.; van Alphen, M.; Berghout, M.; Everts, H.; Beynen, A.C. |
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Title |
An approach to assessment of the efficiency of dietary energy utilization by horses and ponies kept at riding schools |
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Journal Article |
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Year |
2001 |
Publication |
The Veterinary quarterly |
Abbreviated Journal |
Vet Q |
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Volume |
23 |
Issue |
4 |
Pages |
195-198 |
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Keywords |
*Animal Feed; Animal Husbandry; Animals; Body Weight; Dietary Fats; Dietary Fiber; *Energy Intake; *Energy Metabolism; Female; Horses/*physiology; Male |
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Abstract |
The ratio of calculated net energy intake (NEi) to calculate net energy requirement (NEr) might serve as an indicator of the efficiency of dietary energy utilization. The ratio was determined for 93 horses and ponies from 10 riding schools. For each animal with an assumed constant body weight, energy intake and energy requirements were assessed. On average, the estimated NEi was 14% greater than NEr. There was a significant, negative association between crude fibre intake and the NEi: NEr ratio. Earlier work indicated that extra fat intake may lead to over estimation of the calculated energy value of the ration due to changes in macronutrient digestibility. Dietary fat concentration was found to range from 32 to 52 g/kg dry matter (5 to 6 g/MJ net energy), but on the basis of digestibility trials this range in fat concentration is too small to significantly influence the NEi: NEr ratio. This study shows that assessment of the efficiency of dietary energy utilization under normal conditions, on the basis of the NEi: NEr ratio is fraught with uncertainty. |
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Department of Nutrition, Faculty of Veterinary, Medicine, Utrecht University, The Netherlands |
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0165-2176 |
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PMID:11765239 |
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Call Number |
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Serial |
1807 |
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Author |
Heffner, R.S.; Heffner, H.E. |
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Title |
Localization of tones by horses: use of binaural cues and the role of the superior olivary complex |
Type |
Journal Article |
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Year |
1986 |
Publication |
Behavioral Neuroscience |
Abbreviated Journal |
Behav Neurosci |
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Volume |
100 |
Issue |
1 |
Pages |
93-103 |
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Keywords |
Animals; Auditory Pathways/physiology; Auditory Perception/*physiology; Avoidance Learning/physiology; Brain Mapping; Electroshock; Female; Horses/*physiology; Male; Olivary Nucleus/anatomy & histology/*physiology; Orientation/physiology; Pitch Perception/physiology; Sound Localization/*physiology |
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Abstract |
The ability of horses to use binaural time and intensity difference cues to localize sound was assessed in free-field localization tests by using pure tones. The animals were required to discriminate the locus of a single tone pip ranging in frequency from 250 Hz to 25 kHz emitted by loudspeakers located 30 degrees to the left and right of the animals' midline (60 degrees total separation). Three animals were tested with a two-choice procedure; 2 additional animals were tested with a conditioned avoidance procedure. All 5 animals were able to localize 250 Hz, 500 Hz, and 1 kHz but were completely unable to localize 2 kHz and above. Because the frequency of ambiguity for the binaural phase cue delta phi for horses in this test was calculated to be 1.5 kHz, these results indicate that horses can use binaural time differences in the form of delta phi but are unable to use binaural intensity differences. This finding was supported by an unconditioned orientation test involving 4 additional horses, which showed that horses correctly orient to a 500-Hz tone pip but not to an 8-kHz tone pip. Analysis of the superior olivary complex, the brain stem nucleus at which binaural interactions first take place, reveals that the lateral superior olive (LSO) is relatively small in the horse and lacks the laminar arrangement of bipolar cells characteristic of the LSO of most mammals that can use binaural delta I. |
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0735-7044 |
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PMID:3954885 |
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Equine Behaviour @ team @ |
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5634 |
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Author |
De Boyer Des Roches, A.; Richard-Yris, M.-A.; Henry, S.; Ezzaouia, M.; Hausberger, M. |
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Title |
Laterality and emotions: visual laterality in the domestic horse (Equus caballus) differs with objects' emotional value |
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Journal Article |
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Year |
2008 |
Publication |
Physiology & Behavior |
Abbreviated Journal |
Physiol. Behav. |
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Volume |
94 |
Issue |
3 |
Pages |
487-490 |
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Keywords |
Animals; Animals, Newborn; Behavior, Animal/physiology; Dominance, Ocular/*physiology; *Emotions; Exploratory Behavior/physiology; Female; Horses/*physiology; Olfactory Pathways/physiology; Pattern Recognition, Visual/*physiology; Photic Stimulation; Pregnancy; Statistics, Nonparametric; Visual Fields/physiology |
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Lateralization of emotions has received great attention in the last decades, both in humans and animals, but little interest has been given to side bias in perceptual processing. Here, we investigated the influence of the emotional valence of stimuli on visual and olfactory explorations by horses, a large mammalian species with two large monocular visual fields and almost complete decussation of optic fibres. We confronted 38 Arab mares to three objects with either a positive, negative or neutral emotional valence (novel object). The results revealed a gradient of exploration of the 3 objects according to their emotional value and a clear asymmetry in visual exploration. When exploring the novel object, mares used preferentially their right eyes, while they showed a slight tendency to use their left eyes for the negative object. No asymmetry was evidenced for the object with the positive valence. A trend for an asymmetry in olfactory investigation was also observed. Our data confirm the role of the left hemisphere in assessing novelty in horses like in many vertebrate species and the possible role of the right hemisphere in processing negative emotional responses. Our findings also suggest the importance of both hemispheres in the processing positive emotions. This study is, to our knowledge, the first to demonstrate clearly that the emotional valence of a stimulus induces a specific visual lateralization pattern. |
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Address |
UMR CNRS 6552 Ethologie-Evolution-Ecologie, Universite de Rennes 1, Avenue du General Leclerc, Campus de Beaulieu, F-35042 Rennes Cedex, France. a.de-boyer@wanadoo.fr |
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0031-9384 |
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PMID:18455205 |
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Call Number |
Equine Behaviour @ team @ |
Serial |
4762 |
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Author |
Hedberg, Y.; Dalin, A.-M.; Ohagen, P.; Holm, K.R.; Kindahl, H. |
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Title |
Effect of oestrous-cycle stage on the response of mares in a novel object test and isolation test |
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Journal Article |
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Year |
2005 |
Publication |
Reproduction in Domestic Animals = Zuchthygiene |
Abbreviated Journal |
Reprod Domest Anim |
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Volume |
40 |
Issue |
5 |
Pages |
480-488 |
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Keywords |
Animals; Behavior, Animal/*physiology; Cross-Over Studies; Diestrus/*physiology; Estrus/*physiology; Female; Heart Rate/*physiology; Horses/*physiology; Questionnaires |
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Abstract |
In various species, sex, hormonal treatments and oestrous-cycle stage have been shown to affect the animal's response in behavioural tests. Few such studies have been performed in the horse. The main aim of the present study was to investigate whether oestrous-cycle stage affects mares' response to a novel object test and isolation test and, in part, to study whether mares, assumed to suffer from oestrous-related behavioural problems, respond differently in these tests when compared with controls. Twelve mares were tested twice, in oestrus and dioestrus, in a crossover design. Seven behavioural and two heart rate variables were measured for the novel object test and two heart rate variables for the isolation test. Oestrous-cycle stage and whether a mare was classified as a 'problem' mare did not affect the mare's response. However, test order, i.e. the cycle stage a mare was tested in first, affected its reaction. This effect could partly be explained by significant differences between test occasions 1 and 2 in three behavioural variables and one heart rate variable (p < 0.05) in the novel object test. The mares explored the novel object more and had a higher mean heart rate in the first test. Exploring the novel object more could largely be attributed to those mares tested in dioestrus first, perhaps indicating that the mares in oestrus were less receptive to the novel object. The reason for the differences between test occasions could be an effect of learning or habituation. |
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Division of Comparative Reproduction, Obstetrics and Udder Health, Department of Clinical Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden. ylva.hedberg@kv.slu.se |
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0936-6768 |
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PMID:16149956 |
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Call Number |
Equine Behaviour @ team @ |
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5170 |
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Author |
Kaseda, Y.; Ogawa, H.; Khalil, A.M. |
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Title |
Causes of natal dispersal and emigration and their effects on harem formation in Misaki feral horses |
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Journal Article |
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Year |
1997 |
Publication |
Equine Veterinary Journal |
Abbreviated Journal |
Equine Vet J |
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Volume |
29 |
Issue |
4 |
Pages |
262-266 |
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Keywords |
Age Factors; Animal Migration; Animals; Animals, Wild; *Behavior, Animal/physiology; Female; Horses/*physiology/psychology; Male; Reproduction; Seasons; Sexual Behavior, Animal; *Social Behavior |
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Abstract |
Misaki feral horses were separated into 2 herds and the difference between dispersal from natal group (natal dispersal) and dispersal from natal area (natal emigration) was studied. The causes of dispersal and emigration and their effects on harem formation were studied 1979-1994. The number of horses ranged from 73 (mature males: 8, mature females: 26, young males: 8, young females: 3, colt foals: 6, filly foals: 10 and geldings: 12) in 1979 and 86 (mature males: 14, mature females: 37, young males: 12, young females: 7, colt foals: 5, filly foals: 7 and geldings: 4) in 1994 when the present study ended. All 29 males which survived to age 4 years and 58 females which survived to age 3 years left their natal or mother groups at age one to 3. Seventeen of 22 dispersing males and 29 of 39 dispersing females left their natal groups around the birth of their siblings and significant correlations were found between natal dispersal and birth of a sibling. The number of emigrating young males correlated negatively and significantly with the total number of young males in another herd and the number of emigrating young females correlated positively and significantly with the total number of young females in the natal herd. All 13 emigrating stallions which survived to age 5 years formed stable harem groups and a significant correlation was found between natal emigration and harem formation. Twenty-three of 35 resident mares formed stable consort relations with harem stallions and a significant correlation was found between residence and formation of stable consort relations. |
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Faculty of Agriculture, Miyazaki University, Miyazaki-shi, 889-21, Japan |
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0425-1644 |
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PMID:15338905 |
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Equine Behaviour @ team @ |
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4630 |
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Heird, J.C.; Lennon, A.M.; Bell, R.W. |
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Title |
Effects of early experience on the learning ability of yearling horses |
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Journal Article |
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Year |
1981 |
Publication |
Journal of Animal Science |
Abbreviated Journal |
J. Anim Sci. |
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53 |
Issue |
5 |
Pages |
1204-1209 |
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Keywords |
Animals; Conditioning (Psychology); Female; *Handling (Psychology); Horses/*physiology; *Learning |
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Abstract |
Twenty-four yearling Quarter Horse fillies were divided into three groups (I) very limited handling, (II) intermediate handling and (III) extensive handling. At about 14 months of age, each horse was preconditioned for 2 weeks and then run in a simple place-learning T-maze test in which it had to locate its feed. Thirty trials were run daily for 20 days, with the location of the feed changed each day. To retire from the maze, a horse had to meet the criterion: 11 correct responses in 12 tries, with the last eight being consecutive. Horses in Group II required the fewest trials to reach criterion. These horses also learned more and had the highest percentage of correct responses (P less than .05). Mean trainability tended to predict learning ability; however, trainability and trials to criterion were not significantly correlated. Mean emotionality scores indicated a tendency for horses in the intermediately handled group to be less emotional than those in Group I or III. Results indicated that horses with an intermediate amount of handling scored higher on an intermediate test of learning. All handled horses scored higher on learning tests than those not handled. |
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0021-8812 |
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PMID:7319966 |
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Equine Behaviour @ team @ |
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3577 |
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Author |
Mader, D.R.; Price, E.O. |
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Discrimination learning in horses: effects of breed, age and social dominance |
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Journal Article |
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Year |
1980 |
Publication |
Journal of animal science |
Abbreviated Journal |
J. Anim Sci. |
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50 |
Issue |
5 |
Pages |
962-965 |
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Keywords |
Aging; Animals; *Discrimination Learning; Female; Horses/*physiology; *Social Dominance |
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Abstract |
The discrimination learning ability of Quarter Horses and Thoroughbreds was compared by means of visual cues in a three-choice test with food as a reward. Quarter Horses learned significantly faster than Thoroughbreds, and learning progressed more rapidly for both breeds in a second discrimination task. Significant negative correlations were observed between age and rate of learning. Quarter Horses tended to be less reactive than Thoroughbreds, but individual emotional reactivity ratings and learning scores were not correlated. No correlation was found between social dominance and learning scores. Learning studies with horses may provide a better understanding of the behavioral traits that influence trainability in this species. |
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0021-8812 |
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PMID:7390949 |
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refbase @ user @ |
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679 |
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Author |
Arnold, W.; Ruf, T.; Kuntz, R. |
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Title |
Seasonal adjustment of energy budget in a large wild mammal, the Przewalski horse (Equus ferus przewalskii) II. Energy expenditure |
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Journal Article |
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Year |
2006 |
Publication |
The Journal of experimental biology |
Abbreviated Journal |
J Exp Biol |
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Volume |
209 |
Issue |
Pt 22 |
Pages |
4566-4573 |
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Keywords |
Animals; Animals, Wild/*physiology; Body Temperature; Body Temperature Regulation; Eating; *Energy Metabolism; Female; Heart Rate; Horses/*physiology; Male; Motor Activity; Pregnancy; Reproduction; *Seasons |
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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. |
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Research Institute of Wildlife Ecology, University of Veterinary Medicine, Vienna, Savoyenstrasse 1, 1160 Vienna, Austria. walter.arnold@vu-wien.ac.at |
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0022-0949 |
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PMID:17079726 |
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1782 |
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Author |
Bobbert, M.F.; Santamaria, S. |
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Title |
Contribution of the forelimbs and hindlimbs of the horse to mechanical energy changes in jumping |
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Journal Article |
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Year |
2005 |
Publication |
The Journal of Experimental Biology |
Abbreviated Journal |
J Exp Biol |
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Volume |
208 |
Issue |
2 |
Pages |
249-260 |
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Animals; Biomechanics; Forelimb/*physiology; Hindlimb/*physiology; Horses/*physiology; Locomotion/*physiology; Muscle, Skeletal/*physiology; Time Factors |
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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). |
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Institute for Fundamental and Clinical Human Movement Sciences, Vrije Universiteit, van der Boechorstraat 9, NL-1081 BT Amsterdam, The Netherlands. MFBobbert@fbw.vu.nl |
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0022-0949 |
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PMID:15634844 |
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1895 |
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Author |
Carroll, J.; Murphy, C.J.; Neitz, M.; Hoeve, J.N.; Neitz, J. |
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Title |
Photopigment basis for dichromatic color vision in the horse |
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Journal Article |
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Year |
2001 |
Publication |
Journal of Vision |
Abbreviated Journal |
J Vis |
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1 |
Issue |
2 |
Pages |
80-87 |
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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 |
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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. |
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Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee, WI, USA |
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English |
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1534-7362 |
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PMID:12678603 |
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Equine Behaviour @ team @ |
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4060 |
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