| Records |
| Author |
Thiel, D.; Jenni-Eiermann, S.; Palme, R. |
| Title |
Measuring corticosterone metabolites in droppings of capercaillies (Tetrao urogallus) |
Type |
Journal Article |
| Year |
2005 |
Publication |
Annals of the New York Academy of Sciences |
Abbreviated Journal |
Ann N Y Acad Sci |
| Volume |
1046 |
Issue |
|
Pages |
96-108 |
| Keywords |
Adrenocorticotropic Hormone/administration & dosage/analysis/metabolism; Animals; Circadian Rhythm; Corticosterone/administration & dosage/*analysis/*metabolism; Feces/*chemistry; Female; Freezing; Galliformes/*metabolism; Male; Reproducibility of Results; Sex Factors; Temperature; Time Factors; Tritium/diagnostic use |
Abstract  |
The capercaillie (Tetrao urogallus), the largest grouse species in the world, is decreasing in numbers in major parts of its distribution range. Disturbances by human outdoor activities are discussed as a possible reason for this population decline. An indicator for disturbances is the increase of the glucocorticoid corticosterone, a stress hormone, which helps to cope with life-threatening situations. However, repeated disturbances might result in a long-term increase of the basal corticosterone concentration, which can result in detrimental effects like reduced fitness and survival of an animal. To measure corticosterone metabolites (CMs) noninvasively in the droppings of free-living capercaillies, first an enzyme immunoassay (EIA) in captive birds had to be selected and validated. Therefore, the excretion pattern of intravenously injected radiolabeled corticosterone was determined and 3H metabolites were characterized. High-performance liquid chromatography (HPLC) separations of the samples containing peak concentrations revealed that corticosterone was extensively metabolized. The HPLC fractions were tested in several EIAs for glucocorticoid metabolites. The physiological relevance of this method was proved after pharmacological stimulation of the adrenocortical activity. Only the recently established cortisone assay, measuring CMs with a 3,11-dione structure, detected an expressed increase of concentrations following ACTH stimulation. To set up a sampling protocol suited for the field, we examined the influence of various storage conditions and time of day on concentrations of CMs. |
| Address |
Swiss Ornithological Institute, 6204 Sempach, Switzerland. dominik.thiel@vogelwarte.ch |
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Place of Publication |
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| Language |
English |
Summary Language |
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Original Title |
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Series Title |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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| ISSN |
0077-8923 |
ISBN |
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Medium |
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Expedition |
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Conference |
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| Notes |
PMID:16055846 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
4079 |
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| Author |
Crowell-Davis, S.L.; Houpt, K.A.; Carnevale, J. |
| Title |
Feeding and drinking behavior of mares and foals with free access to pasture and water |
Type |
Journal Article |
| Year |
1985 |
Publication |
Journal of animal science |
Abbreviated Journal |
J. Anim Sci. |
| Volume |
60 |
Issue |
4 |
Pages |
883-889 |
| Keywords |
Animals; *Drinking Behavior; *Feeding Behavior; Female; Horses/*physiology; Male; Poaceae; Seasons; Temperature; Time Factors |
| Abstract |
The feeding and drinking behavior of 11 mares and 15 foals living on pasture with free access to water was recorded during 2,340 15-min focal samples taken over 2 yr. Lactating mares on pasture spent about 70% of the day feeding. Foals began feeding on their first day of life. As they grew older, they spent progressively more time feeding, but still spent only 47 +/- 6% of the time feeding by 21 wk of age. Foals fed primarily during the early morning and evening. While grass formed the major proportion of the diet of both foals and mares, they also ate clay, humus, feces, bark, leaves and twigs. Almost all feeding by foals was done while their mothers were feeding. Movement to water sources was frequently, but not invariably, carried out by an entire herd. Frequency (P = .005) but not duration (P greater than .05) of drinking bouts by mares increased as the temperature increased. Frequency was greatest at 30 to 35 C, at which temperature mares drank once every 1.8 h. Frequency of drinking varied with the time of day (P less than .01), being rarest during the early morning (0500 to 0900 h eastern daylight time) and most frequent during the afternoon (1300 to 1700 h). Drinking by foals was very rare. The youngest age at which a foal was observed to drink was 3 wk, and 8 of 15 foals were never observed to drink before weaning. |
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Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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Series Title |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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| ISSN |
0021-8812 |
ISBN |
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Medium |
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Expedition |
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Conference |
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| Notes |
PMID:3988655 |
Approved |
no |
| Call Number |
refbase @ user @ |
Serial |
54 |
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| Author |
Ulloa, A.; Gonzalez-Ceron, L.; Rodriguez, M.H. |
| Title |
Host selection and gonotrophic cycle length of Anopheles punctimacula in southern Mexico |
Type |
Journal Article |
| Year |
2006 |
Publication |
Journal of the American Mosquito Control Association |
Abbreviated Journal |
J Am Mosq Control Assoc |
| Volume |
22 |
Issue |
4 |
Pages |
648-653 |
| Keywords |
Animals; Anopheles/*physiology; Appetitive Behavior/*physiology; Cattle; Female; Horses; Humans; Insect Vectors/*physiology; Malaria/transmission; Mexico; Oviparity/*physiology; Seasons; Time Factors; Vitellogenesis/physiology |
| Abstract |
The host preference, survival rates, and length of the gonotrophic cycle of Anopheles punctimacula was investigated in southern Mexico. Mosquitoes were collected in 15-day separate experiments during the rainy and dry seasons. Daily changes in the parous-nulliparous ratio were recorded and the gonotrophic cycle length was estimated by a time series analysis. Anopheles punctimacula was most abundant during the dry season and preferred animals to humans. The daily survival rate in mosquitoes collected in animal traps was 0.96 (parity rate = 0.86; gonotrophic cycle = 4 days). The length of gonotrophic cycle of 4 days was estimated on the base of a high correlation coefficient value appearing every 4 days. The minimum time estimated for developing mature eggs after blood feeding was 72 h. The proportion of mosquitoes living enough to transmit Plasmodium vivax malaria during the dry season was 0.35. |
| Address |
Centro de Investigacion de Paludismo, Instituto Nacional de Salud Publica, Apartado Postal 537, Tapachula, Chiapas 30700, Mexico |
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| Language |
English |
Summary Language |
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Original Title |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
8756-971X |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
PMID:17304932 |
Approved |
no |
| Call Number |
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Serial |
1830 |
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| Author |
Domjan, M. |
| Title |
Determinants of the enhancement of flavored-water intake by prior exposure |
Type |
Journal Article |
| Year |
1976 |
Publication |
Journal of Experimental Psychology. Animal Behavior Processes |
Abbreviated Journal |
J Exp Psychol Anim Behav Process |
| Volume |
2 |
Issue |
1 |
Pages |
17-27 |
| Keywords |
Animals; Arousal; *Awareness; Behavior, Animal; *Cognition; *Drinking Behavior; Environment; Escape Reaction; Fear; Male; Rats; Saccharin/administration & dosage; *Taste; Thirst; Time Factors; Water Deprivation |
| Abstract |
The intake of a 2.0% sodium saccharin solution in rats was observed to increase as a function of both the number (Experiment 1) and the duration (Experiment 3) of prior periods of access to the saccharin flavor, but did not increase when subjects were maintained on a fluid deprivation procedure in the absence of saccharin exposure (Experiment 2). The enhancement of intake was further influenced by the schedule of saccharin preexposures in the absence of variations in the amount of solution tasted (Experiment 4). The effect was not a function of the opportunity for subjects to determine their own pattern of contact with the saccharin flavor, the opportunity for association of the flavor with hunger and thirst reduction, or the amount of saccharin swallowed during preexposure (Experiment 5). These results suggest that mere exposure to a flavored solution is sufficient to increase subsequent intakes. The phenomenon is discussed in terms of the attenuation of neophobia elicited by the novelty of flavored solutions. |
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English |
Summary Language |
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Original Title |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0097-7403 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
PMID:1249524 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
2790 |
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| Author |
Milgram, N.W.; Head, E.; Muggenburg, B.; Holowachuk, D.; Murphey, H.; Estrada, J.; Ikeda-Douglas, C.J.; Zicker, S.C.; Cotman, C.W. |
| Title |
Landmark discrimination learning in the dog: effects of age, an antioxidant fortified food, and cognitive strategy |
Type |
Journal Article |
| Year |
2002 |
Publication |
Neuroscience and Biobehavioral Reviews |
Abbreviated Journal |
Neurosci Biobehav Rev |
| Volume |
26 |
Issue |
6 |
Pages |
679-695 |
| Keywords |
Age Factors; Aging/*physiology; Analysis of Variance; Animals; Antioxidants/*pharmacology; Blood Chemical Analysis/methods; Cognition/*physiology; *Diet; Discrimination Learning/*drug effects/*physiology; Distance Perception/drug effects/physiology; Dogs/physiology; Female; Male; Psychomotor Performance/physiology; Retention (Psychology)/drug effects/physiology; Spatial Behavior/*drug effects/*physiology; Task Performance and Analysis; Time Factors; Vitamin E/blood |
| Abstract |
The landmark discrimination learning test can be used to assess the ability to utilize allocentric spatial information to locate targets. The present experiments examined the role of various factors on performance of a landmark discrimination learning task in beagle dogs. Experiments 1 and 2 looked at the effects of age and food composition. Experiments 3 and 4 were aimed at characterizing the cognitive strategies used in performance on this task and in long-term retention. Cognitively equivalent groups of old and young dogs were placed into either a test group maintained on food enriched with a broad-spectrum of antioxidants and mitochondrial cofactors, or a control group maintained on a complete and balanced food formulated for adult dogs. Following a wash-in period, the dogs were tested on a series of problems, in which reward was obtained when the animal responded selectively to the object closest to a thin wooden block, which served as a landmark. In Experiment 1, dogs were first trained to respond to a landmark placed directly on top of coaster, landmark 0 (L0). In the next phase of testing, the landmark was moved at successively greater distances (1, 4 or 10 cm) away from the reward object. Learning varied as a function of age group, food group, and task. The young dogs learned all of the tasks more quickly than the old dogs. The aged dogs on the enriched food learned L0 significantly more rapidly than aged dogs on control food. A higher proportion of dogs on the enriched food learned the task, when the distance was increased to 1cm. Experiment 2 showed that accuracy decreased with increased distance between the reward object and landmark, and this effect was greater in old animals. Experiment 3 showed stability of performance, despite using a novel landmark, and new locations, indicating that dogs learned the landmark concept. Experiment 4 found age impaired long-term retention of the landmark task. These results indicate that allocentric spatial learning is impaired in an age-dependent manner in dogs, and that age also affects performance when the distance between the landmark and target is increased. In addition, these results both support a role of oxidative damage in the development of age-associated cognitive dysfunction and indicate that short-term administration of a food enriched with supplemental antioxidants and mitochondrial cofactors can partially reverse the deleterious effects of aging on cognition. |
| Address |
Life Science Division, University of Toronto at Scarborough, 1265 Military Trail, Scarborough, Ont., Canada M1C 1A4. milgram@psych.utoronto.ca |
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Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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Series Title |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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| ISSN |
0149-7634 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
PMID:12479842 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
2806 |
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| Author |
Manson, J.H.; Perry, S.; Stahl, D. |
| Title |
Reconciliation in wild white-faced capuchins (Cebus capucinus) |
Type |
Journal Article |
| Year |
2005 |
Publication |
American journal of primatology |
Abbreviated Journal |
Am. J. Primatol. |
| Volume |
65 |
Issue |
3 |
Pages |
205-219 |
| Keywords |
Aggression; Animals; Cebus/*psychology; Female; Male; Sex Factors; *Social Behavior; Social Dominance; Time Factors |
| Abstract |
The likelihood of reconciliation (defined as preferential peaceful contact among former opponents following conflicts) has been predicted to vary positively with relationship value and compatibility, and negatively with relationship security. Long-term data on wild white-faced capuchins (Cebus capucinus) indicate that dyads consisting of an adult female and an alpha male have high value and compatibility, but low security. Two studies of C. capucinus postconflict (PC) behavior were carried out at Lomas Barbudal Biological Reserve, Costa Rica. One study consisted of 30-min PC and matched control (MC) follows. The second study extracted PC and MC periods from long follows, yielding PC/MC periods averaging 105 min. In study 2, but not study 1, significantly more PC/MC pairs were attracted (former opponents affiliated with each other sooner in the PC period than in the MC period) than were dispersed (former opponents affiliated with each other sooner in the MC period than in the PC period). Reconciliation in study 2 could not be explained as a by-product of former opponents' tendency to seek affiliative contact with conspecifics generally, or of the spatial proximity of opponents following conflicts. Attempted reconciliation was less likely to be followed by renewed aggression when reconciliation attempts were delayed following conflicts. The data were insufficient for a formal test of differences in conciliatory tendency (the difference between the number of attracted and dispersed PC/MC pairs, divided by the total number of pairs) among dyad types to be conducted. |
| Address |
Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany. manson@eva.mpg.de |
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Place of Publication |
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Editor |
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English |
Summary Language |
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Original Title |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0275-2565 |
ISBN |
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Medium |
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Expedition |
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Conference |
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| Notes |
PMID:15772989 |
Approved |
no |
| Call Number |
refbase @ user @ |
Serial |
2874 |
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| Author |
Clayton, H.M. |
| Title |
Classification of collected trot, passage and piaffe based on temporal variables |
Type |
Journal Article |
| Year |
1997 |
Publication |
Equine Veterinary Journal. Supplement |
Abbreviated Journal |
Equine Vet J Suppl |
| Volume |
|
Issue |
23 |
Pages |
54-57 |
| Keywords |
Analysis of Variance; Animals; Discriminant Analysis; Gait/*physiology; Hindlimb/physiology; Horses/*physiology; Locomotion/*physiology; Male; Running/physiology; Time Factors; Videotape Recording; Walking/physiology |
| Abstract |
The objective was to determine whether collected trot, passage and piaffe could be distinguished as separate gaits on the basis of temporal variables. Sagittal plane, 60 Hz videotapes of 10 finalists in the dressage competitions at the 1992 Olympic Games were analysed to measure the temporal variables in absolute terms and as percentages of stride duration. Classification was based on analysis of variance, a graphical method and discriminant analysis. Stride duration was sufficient to distinguish collected trot from passage and piaffe in all horses. The analysis of variance showed that the mean values of most variables differed significantly between passage and piaffe. When hindlimb stance percentage was plotted against diagonal advanced placement percentage, some overlap was found between all 3 movements indicating that individual horses could not be classified reliably in this manner. Using hindlimb stance percentage and diagonal advanced placement percentage as input in a discriminant analysis, 80% of the cases were classified correctly, but at least one horse was misclassified in each movement. When the absolute, rather than percentage, values of the 2 variables were used as input in the discriminant analysis, 90% of the cases were correctly classified and the only misclassifications were between passage and piaffe. However, the 2 horses in which piaffe was misclassified as passage were the gold and silver medallists. In general, higher placed horses tended toward longer diagonal advanced placements, especially in collected trot and passage, and shorter hindlimb stance percentages in passage and piaffe. |
| Address |
Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada |
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Place of Publication |
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English |
Summary Language |
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Original Title |
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Series Title |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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ISBN |
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Medium |
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Expedition |
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Conference |
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| Notes |
PMID:9354290 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
3738 |
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| Author |
Burns, T.E.; Clayton, H.M. |
| Title |
Comparison of the temporal kinematics of the canter pirouette and collected canter |
Type |
Journal Article |
| Year |
1997 |
Publication |
Equine Veterinary Journal. Supplement |
Abbreviated Journal |
Equine Vet J Suppl |
| Volume |
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Issue |
23 |
Pages |
58-61 |
| Keywords |
Animals; Forelimb/physiology; Gait/*physiology; Hindlimb/physiology; Horses/*physiology; Locomotion/*physiology; Movement/physiology; Time Factors; Videotape Recording; Walking/physiology |
| Abstract |
The objectives were to compare the temporal characteristics of canter pirouette strides with collected canter strides in elite dressage horses, and to determine whether the stride kinematics of the canter pirouettes fulfilled the requirements specified in the Federation Equestre Internationale Rules for Dressage Events. Eleven horses were videotaped (60 fields/s) during the individual medal competition at the 1992 Olympic Games. Temporal variables were extracted from the videotapes using standard methods. Two strides were analysed on each of the left and right leads and these were pooled to give mean values for the collected canter and the pirouettes. The pirouettes were completed in 4-9 strides, (mean of 6.4). In the collected canter strides, mean duration of the suspension was 0.013 s. There was no suspension in any of the pirouette strides, instead the stance phases of the leading forelimb and trailing hindlimb overlapped by a mean of 0.163 s. In 9 horses the trailing forelimb contacted the ground before the diagonal leading hindlimb in the collected canter, whereas in the pirouettes the leading hindlimb always made contact before the trailing forelimb (mean dissociation 0.164 s), giving the strides a distinct 4 beat rhythm. Due to increases in advanced placement between the diagonal limb pair and between the 2 forelimbs, the stride duration was longer in the pirouette (0.879 s) than the collected canter (0.629 s). It is concluded that the canter pirouette strides did not maintain the rhythm and timing of the the collected canter strides in any of the 11 horses. |
| Address |
Department of Veterinary Anatomy, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada |
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English |
Summary Language |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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Expedition |
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Conference |
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| Notes |
PMID:9354291 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
3737 |
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| Author |
Labruna, M.B.; Amaku, M. |
| Title |
Rhythm of engorgement and detachment of Anocentor nitens females feeding on horses |
Type |
Journal Article |
| Year |
2006 |
Publication |
Veterinary Parasitology |
Abbreviated Journal |
Vet Parasitol |
| Volume |
137 |
Issue |
3-4 |
Pages |
316-332 |
| Keywords |
Animals; Bites and Stings; Feeding Behavior; Female; Horses/*parasitology; Ixodidae/*physiology; Seasons; Tick Infestations/parasitology/*veterinary; Time Factors |
| Abstract |
The present study evaluated the engorgement and drop-off rhythms of Anocentor nitens females feeding on horses. Drop-off rhythm was evaluated at 6h-intervals (06:00, 12:00, 18:00, and 00:00 h) on horses held in stalls or in a pasture. A new method of marking feeding female ticks (the bowknot technique) was developed to evaluate ticks on horses in pasture that attached to different parts of the horse's body. This technique was highly successful, indicating no significant interference on tick engorgement rate or final tick weight, length and reproductive capability. Horses held in the pasture during the summer produced only 28.2% of the tick detachment during the daylight period from 06:00 to 18:00 h. In contrast, 53.4% of the ticks detached during this same 12 h-period during the winter. This difference was probably related to the longer scotoperiod during the winter. Different drop-off rhythms were observed for females attached to different anatomical parts of the horse's body. For example, ticks attached to the ears, perineum, and tail showed similar drop-off patterns, but were different from ticks attached to mane, rump and other body parts. The idiosoma length of the feeding female ticks was individually measured every 6 h until the engorged female detached naturally. The engorgement rate (increase in millimeters of the body length per hour) was evaluated during the last 96 h of parasitism. The highest engorgement rates were observed during the last 24 h of parasitism (approximately 0.16 mm/h), which were four-fold higher than the engorgement rates of the previous 3 days ( approximately 0.04 mm/h), demonstrating that these lower and higher values corresponded to the slow and rapid feeding phases reported elsewhere. Based on these data, the 6 mm idiosoma length was estimated as the minimal length that would correspond to the time point (i.e. 24 h before detachment) during which ticks would undergo the rapid feeding phase and detach as fully engorged females. When this 6 mm length was tested to estimate the number of engorged females detaching from horses in a period of 24 h, the estimated accuracy varied from 58.5 to 97.7% (mean: 73.3%). |
| Address |
Departamento de Medicina Veterinaria Preventiva e Saude Animal, Faculdade de Medicina Veterinaria e Zootecnia, Universidade de Sao Paulo, Av. Prof. Orlando Marques de Paiva, 87, Cidade Universitaria, Sao Paulo, SP 05508-000, Brazil. labruna@usp.br |
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English |
Summary Language |
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Series Title |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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| ISSN |
0304-4017 |
ISBN |
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Medium |
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Expedition |
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Conference |
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| Notes |
PMID:16481114 |
Approved |
no |
| Call Number |
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Serial |
1877 |
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| Author |
Bobbert, M.F.; Santamaria, S. |
| 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 |
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English |
Summary Language |
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Original Title |
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Series Title |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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0022-0949 |
ISBN |
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| Notes |
PMID:15634844 |
Approved |
no |
| Call Number |
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Serial |
1895 |
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