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Author |
Robert, C.; Valette, J.P.; Denoix, J.M. |
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Title |
The effects of treadmill inclination and speed on the activity of three trunk muscles in the trotting horse |
Type |
Journal Article |
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Year |
2001 |
Publication |
Equine Veterinary Journal |
Abbreviated Journal |
Equine Vet J |
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Volume |
33 |
Issue |
5 |
Pages |
466-472 |
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Keywords |
Animals; Biomechanics; Electromyography/methods/veterinary; Exercise Test/veterinary; Gait/physiology; Horses/*physiology; Muscle, Skeletal/*physiology; Physical Conditioning, Animal; Rectus Abdominis/physiology; Time Factors |
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Abstract |
The purpose of this study was to evaluate the effects of speed and slope on the activity of trunk muscles. The electromyographic (EMG) activity of the splenius (Sp), longissimus dorsi (LD) and rectus abdominis (RA) muscles was recorded with surface electrodes during treadmill locomotion at trot for different combinations of speed (3.5 to 6 m/s) and slope (0 to 6%). Raw EMG signals were processed to determine activity duration, onset and end and integrated EMG (IEMG). For the 3 muscles investigated, onset and end of activity were obtained earlier in the stride cycle when speed increased. A longer duration of activity for the LD, a shorter duration for the RA and an unchanged duration for the Sp were also observed. The IEMG of the latter was poorly affected by speed, whereas it increased linearly with speed for the 2 other muscles. When treadmill inclination changed from 0 to 6%, EMG activity of the LD and RA began and ended later; a longer activity duration was noted. Temporal parameters for Sp did not change with slope. A significant and progressive increase in the IEMG of the 3 muscles was observed with increasing slope. This evaluation of the activity of trunk muscles provides objective data for the use of speed or slope in training programmes. |
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Address |
UMR INRA-DGER, Biomecanique et Pathalogie Locomotrice du Cheval, UP Anatomie, Ecole Nationale Veterinaire d'Alfort, Maisons-Alfort, France |
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English |
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0425-1644 |
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PMID:11558741 |
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Call Number |
Equine Behaviour @ team @ |
Serial |
4052 |
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Author |
Elsaesser, F.; Klobasa, F.; Ellendorff, F. |
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Title |
ACTH stimulation test for the determination of salivary cortisol and of cortisol responses as markers of the training status/fitness of warm-blooded sports horses] |
Type |
Journal Article |
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Year |
2001 |
Publication |
DTW. Deutsche Tierarztliche Wochenschrift |
Abbreviated Journal |
Dtsch Tierarztl Wochenschr |
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Volume |
108 |
Issue |
1 |
Pages |
31-36 |
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Keywords |
Adrenocorticotropic Hormone/*diagnostic use; Animals; Health; Horses/*physiology; Hydrocortisone/*analysis/*secretion; Male; Orchiectomy; *Physical Conditioning, Animal; Running; Saliva/*chemistry; Walking |
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Abstract |
Previous work (Marc et al., 2000) suggested that plasma cortisol responses to treadmill exercise or ACTH injection are a reliable marker for performance evaluation in warmblood horses. For practical purposes blood sample collections and treadmill exercise tests are somewhat troublesome and time consuming. The goal of this study was thus to evaluate the use of saliva for cortisol determination (by direct EIA) as a marker for performance and to investigate the reliability and repeatability of plasma cortisol responses to a single i.v. injection of ACTH (50 micrograms or 250 micrograms). Furthermore, the effect of training horses for 8 weeks 3 times per week covering the same distance (increasing from 3.5 km during the first week to 8 km during the last week) either by trotting (approximately 240 m/min) or by cantering (375 m/min) was investigated. For this purpose initially ten four-year-old Hannovarian geldings, all reared in the same State stud, were used. Mean overall correlation between salivary cortisol and plasma cortisol concentrations was 0.64 when samples of various points of time were used. However, in spite of attempts to standardize saliva sample collection, correlation between salivary cortisol levels and plasma cortisol levels at distinct points of time in different tests were low and significant (r = 0.85, p < 0.02) only in one test. Thus, salivary cortisol measurements for diagnostic purposes are not reliable or useful. The repeatability of plasma cortisol responses to ACTH for untrained and trained horses were r = 0.86 and r = 0.8 respectively (p < or = 0.01 and p < or = 0.05 respectively). Training horses either by trotting or cantering did not affect the cortisol response either to treadmill exercise or to stimulation by ACTH. It is concluded that the relationship between salivary cortisol levels and plasma cortisol levels is not close enough to allow the use of salivary cortisol determination as marker of the training status/fitness of horses. The repeatability of the cortisol response to ACTH is similar to the cortisol response to treadmill exercise. Based on plasma cortisol responses to ACTH or treadmill exercise training horses by cantering at low speed is not superior to training by trotting for the fitness of horses. |
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Institut fur Tierzucht und Tierverhalten Mariensee (FAL), Holtystrasse 10, 31535 Neustadt. elsaesser@tzv.fal.de |
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German |
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Original Title |
ACTH Stimulationstest und Bestimmung von Cortisol im Blut und Speichel zur Bewertung des Trainingszustands/der Kondition beim Warmblutpferd |
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ISSN |
0341-6593 |
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Notes |
PMID:11232423 |
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no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
4053 |
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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 |
Type |
Journal Article |
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Year |
2001 |
Publication |
Journal of Vision |
Abbreviated Journal |
J Vis |
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Volume |
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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ISSN |
1534-7362 |
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Notes |
PMID:12678603 |
Approved |
no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
4060 |
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Author |
Ordakowski-Burk, A.L.; Quinn, R.W.; Shellem, T.A.; Vough, L.R. |
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Title |
Voluntary intake and digestibility of reed canarygrass and timothy hay fed to horses |
Type |
Journal Article |
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Year |
2006 |
Publication |
Journal of Animal Science |
Abbreviated Journal |
J. Anim Sci. |
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Volume |
84 |
Issue |
11 |
Pages |
3104-3109 |
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Keywords |
Animal Feed/*analysis; Animal Nutrition Physiology; Animals; Diet/*veterinary; Digestion/*physiology; Feeding Behavior/*physiology; Horses/*physiology; Male; Poaceae/*metabolism |
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Abstract |
Thousands of hectares of timothy (Phleum pretense L.) grown in the Mid-Atlantic region are infected by cereal rust mite (Abacarus hysterix) that causes discoloration and curling of leaves, decreased nutritional quality, and substantial decreases in yield. A decline in production of timothy hay can lower income for hay producers and cause horse owners to search for alternative hays. Low alkaloid reed canarygrass (Phalaris arundinacea L.) hay has potential as an alternative to timothy hay because it grows well in the Mid-Atlantic region, is believed to have a similar nutrient quality to timothy, and is not as susceptible to cereal rust mite. Eleven mature, stalled Thoroughbred geldings (549 +/- 12.1 kg) that were exercised daily were used to compare voluntary DMI and apparent nutrient DM digestibility of timothy and low-alkaloid Chiefton variety reed canarygrass hay. Horses were paired by age and BW and randomly assigned to timothy or reed canarygrass hay during a 14-d period to measure voluntary DMI followed by a 4-d period to measure apparent DM digestibility. Both hays met the minimum requirements for DE, CP, Ca, P, K, Fe, and Mn, but they did not meet the minimum requirements for Cu, Zn, and Na for horses at maintenance and averaging 550 kg of BW. Timothy hay seemed to have a lower CP concentration (14.4%) compared with reed canarygrass hay (17.1%) and a more desirable Ca:P ratio at 1.6:1 compared with 0.8:1 for reed canarygrass hay. Horses fed timothy consumed more hay (P <0.001) during the voluntary DMI period compared with horses fed reed canarygrass. Greater voluntary DMI of timothy occurred on d 1, 3, and 5 (P <0.05), but DMI was similar for other days. Apparent DM digestibility was greater in horses fed timothy hay by 9.6% compared with horses fed reed canarygrass hay (P <0.05). Horses fed timothy had greater DM digestibility of ADF (P = 0.001), NDF (P = 0.001), sugar (P = 0.05), and Ca (P = 0.001) but lower apparent DM digestibility of CP (P = 0.012) and crude fat (P = 0.004). Timothy hay was superior in voluntary DMI and apparent DM digestibility compared with low-alkaloid reed canarygrass hay fed to horses. |
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Department of Animal and Avian Sciences, University of Maryland, College Park 20742, USA. amyburk@umd.edu |
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ISSN |
1525-3163 |
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Notes |
PMID:17032805 |
Approved |
no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
4236 |
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Author |
Berger, J. |
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Title |
Induced abortion and social factors in wild horses |
Type |
Journal Article |
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Year |
1983 |
Publication |
Nature |
Abbreviated Journal |
Nature |
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Volume |
303 |
Issue |
5912 |
Pages |
59-61 |
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Keywords |
Abortion, Induced/*veterinary; Abortion, Veterinary/*etiology; Aggression/physiology; Animals; Evolution; Female; Horses/*physiology; Humans; Pregnancy; Sexual Behavior, Animal/*physiology |
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Abstract |
Much evidence now suggests that the postnatal killing of young in primates and carnivores, and induced abortions in some rodents, are evolved traits exerting strong selective pressures on adult male and female behaviour. Among ungulates it is perplexing that either no species have developed convergent tactics or that these behaviours are not reported, especially as ungulates have social systems similar to those of members of the above groups. Only in captive horses (Equus caballus) has infant killing been reported. It has been estimated that 40,000 wild horses live in remote areas of the Great Basin Desert of North America (US Department of Interior (Bureau of Land Management), unpublished report), where they occur in harems (females and young) defended by males. Here I present evidence that, rather than killing infants directly, invading males induce abortions in females unprotected by their resident stallions and these females are then inseminated by the new males. |
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English |
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ISSN |
0028-0836 |
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Notes |
PMID:6682487 |
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no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
4365 |
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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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Address |
Faculty of Agriculture, Miyazaki University, Miyazaki-shi, 889-21, Japan |
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English |
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Abbreviated Series Title |
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Edition |
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ISSN |
0425-1644 |
ISBN |
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Notes |
PMID:15338905 |
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no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
4630 |
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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 |
Type |
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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Abstract |
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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English |
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Abbreviated Series Title |
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ISSN |
0031-9384 |
ISBN |
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Notes |
PMID:18455205 |
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no |
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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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Address |
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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English |
Summary Language |
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Abbreviated Series Title |
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Series Volume |
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Edition |
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ISSN |
0936-6768 |
ISBN |
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Notes |
PMID:16149956 |
Approved |
no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
5170 |
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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 |
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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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English |
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0735-7044 |
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PMID:3954885 |
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no |
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Call Number |
Equine Behaviour @ team @ |
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5634 |
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Author |
Timney, B.; Keil, K. |
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Title |
Local and global stereopsis in the horse |
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Journal Article |
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Year |
1999 |
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Vision Research |
Abbreviated Journal |
Vision Res |
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Volume |
39 |
Issue |
10 |
Pages |
1861-1867 |
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Keywords |
Animals; Depth Perception/*physiology; Female; Horses/*physiology; Pattern Recognition, Visual/physiology; Psychophysics; Sensory Thresholds/physiology; Vision, Binocular/physiology; Vision, Monocular/physiology |
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Abstract |
Although horses have laterally-placed eyes, there is substantial binocular overlap, allowing for the possibility that these animals have stereopsis. In the first experiment of the present study we measured local stereopsis by obtaining monocular and binocular depth thresholds for renal depth stimuli. On all measures, the horses' binocular performance was superior to their monocular. When depth thresholds were obtained, binocular thresholds were several times superior to those obtained monocularly, suggesting that the animals could use stereoscopic information when it was available. The binocular thresholds averaged about 15 min arc. In the second experiment we obtained evidence for the presence of global stereopsis by testing the animals' ability to discriminate between random-dot stereograms with and without consistent disparity information. When presented with such stimuli they showed a strong preference for the cyclopean equivalent of the positive stimulus with the real depth. These results provide the first behavioral demonstration of a full range of stereoscopic skills in a lateral-eyed mammal. |
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Address |
Department of Psychology, Faculty of Social Science, University of Western Ontario, London, Canada. timney@julian.uwo.ca |
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English |
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0042-6989 |
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Notes |
PMID:10343877 |
Approved |
yes |
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Call Number |
Equine Behaviour @ team @ |
Serial |
3580 |
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