| Records |
| Author |
Kirkpatrick, J.F.; Turner, A. |
| Title |
Reversibility of action and safety during pregnancy of immunization against porcine zona pellucida in wild mares (Equus caballus) |
Type |
Journal Article |
| Year |
2002 |
Publication |
Reproduction (Cambridge, England) Supplement |
Abbreviated Journal |
Reprod Suppl |
| Volume |
60 |
Issue |
|
Pages |
197-202 |
| Keywords |
Animals; *Animals, Wild; Antigens/administration & dosage; Contraception, Immunologic/methods/*veterinary; Egg Proteins/administration & dosage; Female; Fertility; *Horses; Immunization, Secondary/veterinary; Membrane Glycoproteins/administration & dosage; Population Control; Pregnancy; *Receptors, Cell Surface; Safety; Swine; Time Factors; Vaccines, Contraceptive/*administration & dosage |
| Abstract |
Contraceptive management of publicly valued wildlife species requires safeguards to ensure that these populations are preserved in a healthy state. In addition, reversibility of contraceptive effects and safety in pregnant animals are major concerns. A population of wild horses has been immunized against porcine zona pellucida (PZP) over a 12 year period on Assateague Island National Seashore, MD (ASIS). Mares initially received one or two 65 microg inoculations and once a year 65 microg booster inoculations, all delivered by dart. All young mares aged > 2 years were treated with PZP for 3 consecutive years regardless of whether they have bred successfully and they were then removed from treatment until they had foaled. All mares vaccinated for 1 or 2 consecutive years became fertile again and 69% of mares treated for 3 consecutive years returned to fertility. All five mares treated for 4 or 5 consecutive years have also returned to fertility, but over longer periods of time. Mares treated for 7 consecutive years have not returned to fertility, but several, while still infertile, have started ovulating again. There was no difference in survival rates between foals born to treated and untreated mares, and PZP treatment of pregnant mares did not affect subsequent fertility of their female offspring. |
| Address |
Science and Conservation Center, ZooMontana, Billings 59106, USA. zoolab@wtp.net |
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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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| ISSN |
1477-0415 |
ISBN |
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Medium |
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Expedition |
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Conference |
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Notes  |
PMID:12220160 |
Approved |
no |
| Call Number |
refbase @ user @ |
Serial |
141 |
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| Author |
Kaiser, D.H.; Zentall, T.R.; Neiman, E. |
| Title |
Timing in pigeons: effects of the similarity between intertrial interval and gap in a timing signal |
Type |
Journal Article |
| Year |
2002 |
Publication |
Journal of experimental psychology. Animal behavior processes |
Abbreviated Journal |
J Exp Psychol Anim Behav Process |
| Volume |
28 |
Issue |
4 |
Pages |
416-422 |
| Keywords |
Animals; *Attention; Columbidae; *Conditioning, Operant; Discrimination Learning; Mental Recall; Probability Learning; *Reinforcement (Psychology); *Reinforcement Schedule; Retention (Psychology); Time Factors; *Time Perception/physiology |
| Abstract |
Previous research suggests that when a fixed interval is interrupted (known as the gap procedure), pigeons tend to reset memory and start timing from 0 after the gap. However, because the ambient conditions of the gap typically have been the same as during the intertrial interval (ITI), ambiguity may have resulted. In the present experiment, the authors found that when ambient conditions during the gap were similar to the ITI, pigeons tended to reset memory, but when ambient conditions during the gap were different from the ITI, pigeons tended to stop timing, retain the duration of the stimulus in memory, and add to that time when the stimulus reappeared. Thus, when the gap was unambiguous, pigeons timed accurately. |
| Address |
Department of Psychology, East Carolina University, Greenville, North Carolina 27858, USA. kaiserd@mail.ecu.edu |
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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 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:12395499 |
Approved |
no |
| Call Number |
refbase @ user @ |
Serial |
238 |
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| Author |
Waite, T.A. |
| Title |
Interruptions improve choice performance in gray jays: prolonged information processing versus minimization of costly errors |
Type |
Journal Article |
| Year |
2002 |
Publication |
Animal Cognition |
Abbreviated Journal |
Anim. Cogn. |
| Volume |
5 |
Issue |
4 |
Pages |
209-214 |
| Keywords |
Animals; *Behavior, Animal; *Choice Behavior; Female; Learning; Male; Models, Biological; Motivation; Reinforcement Schedule; Songbirds/*physiology; Time Factors |
| Abstract |
Under the assumption that selection favors minimization of costly errors, erroneous choice may be common when its fitness cost is low. According to an adaptive-choice model, this cost depends on the rate at which an animal encounters the choice: the higher this rate, the smaller the cost of choosing a less valuable option. Errors should thus be more common when interruptions to foraging are shorter. A previous experiment supported this prediction: gray jays, Perisoreus canadensis, were more error prone when subjected to shorter delays to access to food rewards. This pattern, though, is also predicted by an attentional-constraints model. Because the subjects were able to inspect the rewards during delays, their improved performance when subjected to longer delays could have been a byproduct of the experimentally prolonged opportunity for information processing. To evaluate this possibility, a follow-up experiment manipulated both delay to access and whether rewards could be inspected during delays. Depriving jays of the opportunity to inspect rewards (using opaque lids) induced only a small, nonsignificant increase in error rate. This effect was independent of length of delay and so the jays' improved performance when subjected to longer delays was not simply a byproduct of prolonged information processing. More definitively, even when the jays were prevented from inspecting rewards during delays, their performance improved when subjected to longer delays. The findings are thus consistent with the adaptive-choice model. |
| Address |
Department of Evolution, Ecology, and Organismal Biology, Ohio State University, 1735 Neil Avenue, Columbus, OH 43210-1293, USA. waite.1@osu.edu |
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Thesis |
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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 Volume |
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Series Issue |
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Edition |
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| ISSN |
1435-9448 |
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:12461598 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
2592 |
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| Author |
Reichmuth Kastak, C.; Schusterman, R.J. |
| Title |
Long-term memory for concepts in a California sea lion ( Zalophus californianus) |
Type |
Journal Article |
| Year |
2002 |
Publication |
Animal Cognition |
Abbreviated Journal |
Anim. Cogn. |
| Volume |
5 |
Issue |
4 |
Pages |
225-232 |
| Keywords |
Animals; Concept Formation; Female; Memory/*physiology; Mental Processes; Sea Lions/physiology/*psychology; Time Factors |
| Abstract |
An adult California sea lion ( Zalophus californianus) with extensive experience in performing discrimination learning tasks was tested to evaluate her long-term memory for two previously learned concepts. An associative concept, that of equivalence classification, was retested after a retention interval of approximately 1 year. The sea lion had originally shown emergent equivalence classification with nonsimilarity-based classes of stimuli in a simple discrimination repeated-reversal procedure as well as in a matching-to-sample procedure. The 1-year memory test revealed no decrement in classification performance in either procedure. A relational concept, that of generalized identity matching, was retested after approximately 10 years. The sea lion had originally received trial-and-error exemplar training with identity matching-to-sample problems prior to transferring the concept to novel stimulus configurations. In the 10-year memory test, the sea lion immediately and reliably applied the previously established identity concept to familiar and novel sets of matching problems. These are the first reports of long-term conceptual memory in a nonprimate species. The experimental findings are consistent with a variety of observations of sea lions in natural settings, which indicate that natal sites, feeding areas, and individuals may be remembered over long periods of time. |
| Address |
Long Marine Laboratory, University of California at Santa Cruz, 100 Shaffer Road, Santa Cruz, CA 95060, USA. coll@cats.ucsc.edu |
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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 Volume |
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Series Issue |
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Edition |
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| ISSN |
1435-9448 |
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:12461600 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
2590 |
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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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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 |
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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Thesis |
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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 Editor |
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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 |
Touma, C.; Sachser, N.; Mostl, E.; Palme, R. |
| Title |
Effects of sex and time of day on metabolism and excretion of corticosterone in urine and feces of mice |
Type |
Journal Article |
| Year |
2003 |
Publication |
General and Comparative Endocrinology |
Abbreviated Journal |
Gen Comp Endocrinol |
| Volume |
130 |
Issue |
3 |
Pages |
267-278 |
| Keywords |
Animals; Chromatography, High Pressure Liquid; Circadian Rhythm/*physiology; Corticosterone/*metabolism/urine; Feces/*chemistry; Female; Immunoenzyme Techniques; Kinetics; Male; Mice; Mice, Inbred C57BL; Reference Values; Sex Factors; Stress/metabolism; Time Factors; Tritium |
| Abstract |
Non-invasive techniques to monitor stress hormones in small animals like mice offer several advantages and are highly demanded in laboratory as well as in field research. Since knowledge about the species-specific metabolism and excretion of glucocorticoids is essential to develop such a technique, we conducted radiometabolism studies in mice (Mus musculus f. domesticus, strain C57BL/6J). Each mouse was injected intraperitoneally with 740 kBq of 3H-labelled corticosterone and all voided urine and fecal samples were collected for five days. In a first experiment 16 animals (eight of each sex) received the injection at 9 a.m., while eight mice (four of each sex) were injected at 9 p.m. in a second experiment. In both experiments radioactive metabolites were recovered predominantly in the feces, although males excreted significantly higher proportions via the feces (about 73%) than females (about 53%). Peak radioactivity in the urine was detected within about 2h after injection, while in the feces peak concentrations were observed later (depending on the time of injection: about 10h postinjection in experiment 1 and about 4h postinjection in experiment 2, thus proving an effect of the time of day). The number and relative abundance of fecal [3H]corticosterone metabolites was determined by high performance liquid chromatography (HPLC). The HPLC separations revealed that corticosterone was extensively metabolized mainly to more polar substances. Regarding the types of metabolites formed, significant differences were found between males and females, but not between the experiments. Additionally, the immunoreactivity of these metabolites was assessed by screening the HPLC fractions with four enzyme immunoassays (EIA). However, only a newly established EIA for 5alpha-pregnane-3beta,11beta,21-triol-20-one (measuring corticosterone metabolites with a 5alpha-3beta,11beta-diol structure) detected several peaks of radioactive metabolites with high intensity in both sexes, while the other EIAs showed only minor immunoreactivity. Thus, our study for the first time provides substantial information about metabolism and excretion of corticosterone in urine and feces of mice and is the first demonstrating a significant impact of the animals' sex and the time of day. Based on these data it should be possible to monitor adrenocortical activity non-invasively in this species by measuring fecal corticosterone metabolites with the newly developed EIA. Since mice are extensively used in research world-wide, this could open new perspectives in various fields from ecology to behavioral endocrinology. |
| Address |
Department of Behavioral Biology, Institute of Neuro and Behavioral Biology, University of Muenster, Badestrasse 9, D-48149 Muenster, Germany. touma@uni-muenster.de |
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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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| ISSN |
0016-6480 |
ISBN |
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Medium |
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Expedition |
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Conference |
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| Notes |
PMID:12606269 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
4086 |
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| Author |
Williams, J.L.; Friend, T.H.; Collins, M.N.; Toscano, M.J.; Sisto-Burt, A.; Nevill, C.H. |
| Title |
Effects of imprint training procedure at birth on the reactions of foals at age six months |
Type |
Journal Article |
| Year |
2003 |
Publication |
Equine Veterinary Journal |
Abbreviated Journal |
Equine Vet J |
| Volume |
35 |
Issue |
2 |
Pages |
127-132 |
| Keywords |
Age Factors; Animal Husbandry/methods; Animals; Animals, Newborn/*psychology; *Behavior, Animal; *Bonding, Human-Pet; Female; Handling (Psychology); Horses/*psychology; Humans; *Imprinting (Psychology); Male; Random Allocation; Socialization; Time Factors |
| Abstract |
REASONS FOR PERFORMING STUDY: While imprint training procedures have been promoted in popular magazines, they have received limited scientific investigation. OBJECTIVES: To determine the effects of a neonatal imprint training procedure on 6-month-old foals and to determine if any one session had a greater effect than others. METHODS: Foals (n = 131) were divided into the following treatments: no imprint training, imprint training at birth, 12, 24 and 48 h after birth or imprint training only at birth, 12, 24, 48, or 72 h after birth. Foals then received minimal human handling until they were tested at 6 months. RESULTS: During training, time to complete exposure to the stimulus was significant for only 2 of 6 stimuli. Percentage change in baseline heart rate was significant for only 2 of 10 stimuli. These 4 effects were randomly spread across treatments. CONCLUSIONS: Neither the number of imprint training sessions (0, 1, or 4) nor the timing of imprint training sessions (none, birth, 12, 24, 48, or 72 h after birth) influenced the foal's behaviour at 6 months of age. POTENTIAL CLINICAL RELEVANCE: In this study, imprint training did not result in better behaved, less reactive foals. |
| Address |
Department of Animal Science, 2471 TAMUS, Texas A&M University College Station, Texas 77845-2471, USA |
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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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| ISSN |
0425-1644 |
ISBN |
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Medium |
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Expedition |
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Conference |
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| Notes |
PMID:12638787 |
Approved |
no |
| Call Number |
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Serial |
1908 |
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| Author |
Rands, S.A.; Cowlishaw, G.; Pettifor, R.A.; Rowcliffe, J.M.; Johnstone, R.A. |
| Title |
Spontaneous emergence of leaders and followers in foraging pairs |
Type |
Journal Article |
| Year |
2003 |
Publication |
Nature |
Abbreviated Journal |
Nature |
| Volume |
423 |
Issue |
6938 |
Pages |
432-434 |
| Keywords |
Animals; *Energy Metabolism; Food; *Food Chain; *Models, Biological; Motor Activity; *Social Behavior; Time Factors |
| Abstract |
Animals that forage socially often stand to gain from coordination of their behaviour. Yet it is not known how group members reach a consensus on the timing of foraging bouts. Here we demonstrate a simple process by which this may occur. We develop a state-dependent, dynamic game model of foraging by a pair of animals, in which each individual chooses between resting or foraging during a series of consecutive periods, so as to maximize its own individual chances of survival. We find that, if there is an advantage to foraging together, the equilibrium behaviour of both individuals becomes highly synchronized. As a result of this synchronization, differences in the energetic reserves of the two players spontaneously develop, leading them to adopt different behavioural roles. The individual with lower reserves emerges as the 'pace-maker' who determines when the pair should forage, providing a straightforward resolution to the problem of group coordination. Moreover, the strategy that gives rise to this behaviour can be implemented by a simple 'rule of thumb' that requires no detailed knowledge of the state of other individuals. |
| Address |
Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK. s.rands@zoo.cam.ac.uk |
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Thesis |
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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 Issue |
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Edition |
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| ISSN |
0028-0836 |
ISBN |
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Medium |
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Expedition |
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Conference |
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| Notes |
PMID:12761547 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
5138 |
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| Author |
Gavrilova, O.; Haluzik, M.; Matsusue, K.; Cutson, J.J.; Johnson, L.; Dietz, K.R.; Nicol, C.J.; Vinson, C.; Gonzalez, F.J.; Reitman, M.L. |
| Title |
Liver peroxisome proliferator-activated receptor gamma contributes to hepatic steatosis, triglyceride clearance, and regulation of body fat mass |
Type |
Journal Article |
| Year |
2003 |
Publication |
The Journal of biological chemistry |
Abbreviated Journal |
J Biol Chem |
| Volume |
278 |
Issue |
36 |
Pages |
34268-34276 |
| Keywords |
Adipose Tissue/*metabolism; Animals; Blotting, Southern; Blotting, Western; Female; Hypoglycemia/genetics; Insulin Resistance/genetics; Lipid Metabolism; Liver/*metabolism; Liver Diseases/genetics/*metabolism; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Mice, Transgenic; RNA/metabolism; Receptors, Cytoplasmic and Nuclear/*genetics/*physiology; Recombination, Genetic; Thiazoles/pharmacology; *Thiazolidinediones; Time Factors; Transcription Factors/*genetics/*physiology; Triglycerides/*metabolism |
| Abstract |
Peroxisome proliferator-activated receptor gamma (PPAR gamma) is a nuclear receptor that mediates the antidiabetic effects of thiazolidinediones. PPAR gamma is present in adipose tissue and becomes elevated in fatty livers, but the roles of specific tissues in thiazolidinedione actions are unclear. We studied the function of liver PPAR gamma in both lipoatrophic A-ZIP/F-1 (AZIP) and wild type mice. In AZIP mice, ablation of liver PPAR gamma reduced the hepatic steatosis but worsened the hyperlipidemia, triglyceride clearance, and muscle insulin resistance. Inactivation of AZIP liver PPAR gamma also abolished the hypoglycemic and hypolipidemic effects of rosiglitazone, demonstrating that, in the absence of adipose tissue, the liver is a primary and major site of thiazolidinedione action. In contrast, rosiglitazone remained effective in non-lipoatrophic mice lacking liver PPAR gamma, suggesting that adipose tissue is the major site of thiazolidinedione action in typical mice with adipose tissue. Interestingly, mice without liver PPAR gamma, but with adipose tissue, developed relative fat intolerance, increased adiposity, hyperlipidemia, and insulin resistance. Thus, liver PPAR gamma regulates triglyceride homeostasis, contributing to hepatic steatosis, but protecting other tissues from triglyceride accumulation and insulin resistance. |
| Address |
Diabetes Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA. oksanag@bdg10.niddk.nih.gov |
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Thesis |
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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 Editor |
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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 |
0021-9258 |
ISBN |
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Medium |
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Expedition |
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Conference |
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| Notes |
PMID:12805374 |
Approved |
no |
| Call Number |
refbase @ user @ |
Serial |
81 |
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