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Author Acuna, B.D.; Sanes, J.N.; Donoghue, J.P. doi  openurl
  Title Cognitive mechanisms of transitive inference Type Journal Article
  Year 2002 Publication Experimental brain research. Experimentelle Hirnforschung. Experimentation cerebrale Abbreviated Journal Exp Brain Res  
  Volume 146 Issue 1 Pages 1-10  
  Keywords Adolescent; Adult; Attention/*physiology; Cognition/*physiology; Female; Humans; Learning/physiology; Linear Models; Male; Photic Stimulation; Psychomotor Performance/physiology; Reaction Time/physiology  
  Abstract We examined how the brain organizes interrelated facts during learning and how the facts are subsequently manipulated in a transitive inference (TI) paradigm (e.g., if A<B and B<C, then A<C). This task determined features such as learned facts and behavioral goals, but the learned facts could be organized in any of several ways. For example, if one learns a list by operating on paired items, the pairs may be stored individually as separate facts and reaction time (RT) should decrease with learning. Alternatively, the pairs may be stored as a single, unified list, which may yield a different RT pattern. We characterized RT patterns that occurred as participants learned, by trial and error, the predetermined order of 11 shapes. The task goal was to choose the shape occurring closer to the end of the list, and feedback about correctness was provided during this phase. RT increased even as its variance decreased during learning, suggesting that the learnt knowledge became progressively unified into a single representation, requiring more time to manipulate as participants acquired relational knowledge. After learning, non-adjacent (NA) list items were presented to examine how participants reasoned in a TI task. The task goal also required choosing from each presented pair the item occurring closer to the list end, but without feedback. Participants could solve the TI problems by applying formal logic to the previously learnt pairs of adjacent items; alternatively, they could manipulate a single, unified representation of the list. Shorter RT occurred for NA pairs having more intervening items, supporting the hypothesis that humans employ unified mental representations during TI. The response pattern does not support mental logic solutions of applying inference rules sequentially, which would predict longer RT with more intervening items. We conclude that the brain organizes information in such a way that reflects the relations among the items, even if the facts were learned in an arbitrary order, and that this representation is subsequently used to make inferences.  
  Address Department of Neuroscience, Box 1953, Brown Medical School, Providence, RI 02912, USA  
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  Series Volume Series Issue Edition  
  ISSN 0014-4819 ISBN Medium  
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  Notes PMID:12192572 Approved (up) no  
  Call Number refbase @ user @ Serial 602  
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Author van Dierendonck, M.C.; Bandi, N.; Batdorj, D.; Dugerlham, S.; Munkhtsog, B. url  openurl
  Title Behavioural observations of reintroduced Takhi or Przewalski horses (Equus ferus przewalskii) in Mongolia Type Journal Article
  Year 1996 Publication Applied Animal Behaviour Science Abbreviated Journal Appl. Anim. Behav. Sci.  
  Volume 50 Issue 2 Pages 95-114  
  Keywords Horse; Przewalski's horse; Reintroduction; Time budget; Social organisation; Basic reference dataset  
  Abstract During 1992 and 1993, 14 reintroduced Przewalski Horses or Takhi (Equus ferus przewalskii) were studied in the Hustain Nuruu Mountain Steppe reserve in Mongolia. Most of the individuals did not know each other before reintroduction. These Takhi were the first of five groups due to be released in the reserve after an acclimatisation period of at least 1 year. During acclimatisation the Takhi, lived visually and acoustically separately, in fenced enclosures of approximately 45 ha each. The observations, mostly scan-sampling, were carried out in each season. The observation bouts were divided over six periods and over two harem herds. Two of the periods were in the same consecutive seasons, so comparison over the years was possible. Social integration within the Takhi herds was very high from the beginning, as described by the spatial relation and synchronisation data. Between 50 and 89% of the observation time, the behaviour of all herd members was synchronised. The amount of time spent grazing by the Takhi (30-68% of the daylight period) was similar to that of feral horses and Takhi in captivity and semi-reserves. The Takhi tended to rest in the morning and have a bimodal period of grazing at dawn and in the afternoon. The Takhi displayed clear habitat preferences for certain activities. They had a strong preference to rest at the highest point in their enclosure. They fed preferably on two or three different vegetation types (with five types available in each enclosure). The amount of time spent grazing during the non-growing seasons (49 +/- 15%) indicates that the feeding value and availability of food were sufficient. Health changes were detected adequately using condition scoring sheets. No supplementary food or water was supplied during the harsh winters. Moreover, low mortality rates and high reproductive success show that the mountain steppe is a habitat which is potentially suitable for establishing a healthy Takhi population. Takhi is the first species to return to its native habitat after living only in zoos for so many generations.  
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  Notes Approved (up) no  
  Call Number refbase @ user @ Serial 762  
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Author Rapin, V.; Poncet, P.A.; Burger, D.; Mermod, C.; Richard, M.A. doi  openurl
  Title [Measurement of the attention time in the horse] Type Journal Article
  Year 2007 Publication Schweizer Archiv fur Tierheilkunde Abbreviated Journal Schweiz Arch Tierheilkd  
  Volume 149 Issue 2 Pages 77-83  
  Keywords Age Factors; Animals; *Attention/physiology; Conditioning, Operant; Cross-Over Studies; Female; Horses/*physiology; Learning/*physiology; Male; Memory/*physiology; Time Factors  
  Abstract A study carried out on 49 horses showed that it is possible to measure the attention time by operant conditioning. After teaching horses an instrumental task using a signal, we were then able to test their attention time by asking them to prolong it increasingly while setting success and failure criteria. Two tests were performed 3 weeks apart. The 2nd test was feasible without relearning, a proof of memory, and was repeatable, a proof of consistency in the attention time. A significant difference was observed between the 3 age groups. Young horses often performed very well during the 1st test but their attention dropped in the 2nd test while older horses were more stable with respect to attention and even increased it slightly. The study shows that there are individual differences but it was not possible to prove a significant influence of breed, gender and paternal influence. Consequently, learning appears to be one of the most interesting approaches for evaluating the attention of horses and for observing their behaviour.  
  Address Laboratoire d'Ecoethologie, Universite de Neuchatel, Suisse. veronique.rapin@unine.ch  
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  Language French Summary Language Original Title Mesure de la duree d'attention chez le cheval  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0036-7281 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:17343134 Approved (up) no  
  Call Number Serial 1770  
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Author Christensen, J.W.; Rundgren, M.; Olsson, K. openurl 
  Title Training methods for horses: habituation to a frightening stimulus Type Journal Article
  Year 2006 Publication Equine veterinary journal Abbreviated Journal Equine Vet J  
  Volume 38 Issue 5 Pages 439-443  
  Keywords Animals; Behavior, Animal/*physiology; *Conditioning (Psychology); *Fear; Heart Rate/*physiology; Horses/physiology/*psychology; Learning; Male; Random Allocation; *Reinforcement (Psychology); Safety; Time Factors  
  Abstract REASONS FOR PERFORMING STUDY: Responses of horses in frightening situations are important for both equine and human safety. Considerable scientific interest has been shown in development of reactivity tests, but little effort has been dedicated to the development of appropriate training methods for reducing fearfulness. OBJECTIVES: To investigate which of 3 different training methods (habituation, desensitisation and counter-conditioning) was most effective in teaching horses to react calmly in a potentially frightening situation. HYPOTHESES: 1) Horses are able to generalise about the test stimulus such that, once familiar with the test stimulus in one situation, it appears less frightening and elicits a reduced response even when the stimulus intensity is increased or the stimulus is presented differently; and 2) alternative methods such as desensitisation and counter-conditioning would be more efficient than a classic habituation approach. METHODS: Twenty-seven naive 2-year-old Danish Warmblood stallions were trained according to 3 different methods, based on classical learning theory: 1) horses (n = 9) were exposed to the full stimulus (a moving, white nylon bag, 1.2 x 0.75 m) in 5 daily training sessions until they met a predefined habituation criterion (habituation); 2) horses (n = 9) were introduced gradually to the stimulus and habituated to each step before the full stimulus was applied (desensitisation); 3) horses (n = 9) were trained to associate the stimulus with a positive reward before being exposed to the full stimulus (counter-conditioning). Each horse received 5 training sessions of 3 min per day. Heart rate and behavioural responses were recorded. RESULTS: Horses trained with the desensitisation method showed fewer flight responses in total and needed fewer training sessions to learn to react calmly to test stimuli. Variations in heart rate persisted even when behavioural responses had ceased. In addition, all horses on the desensitisation method eventually habituated to the test stimulus whereas some horses on the other methods did not. CONCLUSIONS AND POTENTIAL RELEVANCE: Desensitisation appeared to be the most effective training method for horses in frightening situations. Further research is needed in order to investigate the role of positive reinforcement, such as offering food, in the training of horses.  
  Address Danish Institute of Agricultural Sciences, Department of Animal Health, Welfare and Nutrition, Tjele, Denmark  
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  ISSN 0425-1644 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16986605 Approved (up) no  
  Call Number Serial 1783  
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Author Ulloa, A.; Gonzalez-Ceron, L.; Rodriguez, M.H. openurl 
  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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  ISSN 8756-971X ISBN Medium  
  Area Expedition Conference  
  Notes PMID:17304932 Approved (up) no  
  Call Number Serial 1830  
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Author Elhay, M.; Newbold, A.; Britton, A.; Turley, P.; Dowsett, K.; Walker, J. doi  openurl
  Title Suppression of behavioural and physiological oestrus in the mare by vaccination against GnRH Type Journal Article
  Year 2007 Publication Australian Veterinary Journal Abbreviated Journal Aust Vet J  
  Volume 85 Issue 1-2 Pages 39-45  
  Keywords Animals; Antibodies/blood; Estradiol/blood; *Estrus/drug effects/physiology; Female; Gonadotropin-Releasing Hormone/*immunology/*pharmacology; Horses/*physiology; Luteinizing Hormone/blood; Ovulation/*drug effects/physiology; Progesterone/blood; Safety; Sexual Behavior, Animal/drug effects/physiology; Time Factors; Vaccination/veterinary  
  Abstract OBJECTIVE: To examine the immunogenicity of an equine immunocontraceptive vaccine and its efficacy in controlling hormone-related behaviour. DESIGN: A total of 24 mares at two sites in Australia were vaccinated with an immunocontraceptive vaccine comprising gonadotrophin releasing hormone (GnRH) conjugated to a carrier protein in immunostimulating complex as an adjuvant. Twelve animals at each site received a placebo of adjuvant alone and served as controls for seasonal oestrus, hormonal and behaviour patterns. Animals were observed for injection site reactions, ovarian and follicular activity, and serum levels of antibody, 17beta-oestradiol and progesterone in the weeks following vaccination. Mares were also examined for oestrous behaviour by teasing with a stallion. RESULTS: All mares responded to vaccination. Two weeks following the second vaccination there was a peak in antibody response to GnRH that declined gradually over the following weeks. Commensurate with the elevated anti-GnRH antibody there was a marked effect on ovarian activity with a reduction in 17beta-oestradiol and progesterone levels in the 24 vaccinated mares. There was also a reduction of oestrus-related behaviour as determined by a teaser stallion. This effect lasted a minimum of 3 months and correlated with the initial level of antibody response. CONCLUSION: Following a conventional two-dose immunisation regime this commercially available equine immunocontraceptive vaccine was effective at inhibiting oestrous behaviour for at least 3 months. This vaccine has a high level of safety since there were no significant local reactions nor were there any adverse systemic responses to vaccination.  
  Address Veterinary Medicines Research and Development, Pfizer Animal Health, Parkville, VIC 3052. Martin.Elhay@pfizer.com  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0005-0423 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:17300452 Approved (up) no  
  Call Number Serial 1831  
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Author Lee, J.; Paik, M. openurl 
  Title Sex preferences and fertility in South Korea during the year of the Horse Type Journal Article
  Year 2006 Publication Demography Abbreviated Journal Demography  
  Volume 43 Issue 2 Pages 269-292  
  Keywords Asian Continental Ancestry Group/*psychology; *Astrology; Attitude/*ethnology; Chronology; *Culture; Female; *Fertility; Humans; Korea; Male; *Mythology; Risk; *Sex Ratio; Social Desirability; Time  
  Abstract Since antiquity, people in several East Asian countries, such as China, Japan, and South Korea, have believed that a person is destined to possess specific characteristics according to the sign of the zodiac under which he or she was born. South Koreans, in particular, have traditionally considered that the year of the Horse bears inauspicious implications for the birth of daughters. Using monthly longitudinal data at the region level in South Korea between 1970 and 2003, we found that in the year of the Horse, the sex ratio at birth significantly increased while fertility decreased.  
  Address Department of Economics, Sam M. Walton College of Business, Business Building 402, University of Arkansas, Fayetteville, AR 72701-1201, USA. jlee@walton.uark.edu  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0070-3370 ISBN Medium  
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  Notes PMID:16889129 Approved (up) no  
  Call Number Serial 1867  
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Author Labruna, M.B.; Amaku, M. doi  openurl
  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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  ISSN 0304-4017 ISBN Medium  
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  Notes PMID:16481114 Approved (up) no  
  Call Number Serial 1877  
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Author Piccione, G.; Caola, G.; Refinetti, R. doi  openurl
  Title Temporal relationships of 21 physiological variables in horse and sheep Type Journal Article
  Year 2005 Publication Comparative Biochemistry and Physiology. Part A, Molecular & Integrative Physiology Abbreviated Journal Comp Biochem Physiol A Mol Integr Physiol  
  Volume 142 Issue 4 Pages 389-396  
  Keywords Animals; Behavior, Animal/physiology; Blood Glucose/physiology; Body Temperature/*physiology; Circadian Rhythm/*physiology; Female; Horses/*physiology; Melatonin/blood/*physiology; Motor Activity/*physiology; Rectum/physiology; Sheep/*physiology; Time Factors  
  Abstract Daily or circadian oscillation has been documented in a variety of physiological and behavioral processes. Although individual variables have been studied in great detail, very few studies have been conducted on the temporal relationships between the rhythms of different variables. It is not known whether the circadian pacemaker generates each and every rhythm individually or whether most rhythms are simply derived from a few clock-controlled rhythms. As a first step in elucidating this issue, 21 physiological variables were recorded simultaneously in horse and sheep. The results indicated that, in both species, different variables exhibit different degrees of daily rhythmicity and reach their daily peaks at different times of the day. The variables exhibiting strongest rhythmicity were locomotor activity, rectal temperature, and plasma concentrations of melatonin and glucose. Comparison of rhythmicity and acrophase in the various rhythms allowed inferences to be made about mechanisms of causation.  
  Address Dipartimento di Morfologia, Biochimica, Fisiologia e Produzioni Animali, Facolta di Medicina Veterinaria, Universita degli Studi di Messina, 98168 Messina, Italy  
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  Series Volume Series Issue Edition  
  ISSN 1095-6433 ISBN Medium  
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  Notes PMID:16290083 Approved (up) no  
  Call Number Serial 1884  
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Author Macfadden, B.J. doi  openurl
  Title Evolution. Fossil horses--evidence for evolution Type Journal Article
  Year 2005 Publication Science (New York, N.Y.) Abbreviated Journal Science  
  Volume 307 Issue 5716 Pages 1728-1730  
  Keywords Animals; Body Size; DNA, Mitochondrial; Diet; *Equidae/anatomy & histology/classification/genetics; *Evolution; Feeding Behavior; *Fossils; *Horses/anatomy & histology/classification/genetics; Paleodontology; Phylogeny; Time; Tooth/anatomy & histology  
  Abstract  
  Address Florida Museum of Natural History, University of Florida, Gainesville, FL 32611, USA. bmacfadd@flmnh.ufl.edu  
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  ISSN 1095-9203 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15774746 Approved (up) no  
  Call Number Serial 1892  
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