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Author Scherer, W.F.; Madalengoitia, J.; Flores, W.; Acosta, M. openurl 
  Title Ecologic studies of Venezuelan encephalitis virus in Peru during 1970-1971 Type Journal Article
  Year 1975 Publication American Journal of Epidemiology Abbreviated Journal Am J Epidemiol  
  Volume 101 Issue 4 Pages 347-355  
  Keywords Animals; Antibodies, Viral; Cricetinae/immunology; Culicidae/microbiology; *Disease Vectors; Ecology; *Encephalitis Virus, Venezuelan Equine/immunology/isolation & purification; Encephalomyelitis, Equine/immunology/microbiology/transmission; Female; Hemagglutination Inhibition Tests; Horses/immunology; Humans; Neutralization Tests; Peru  
  Abstract (down) Venezuelan encephalitis (VE) virus has intermittently produced epidemics and equine epizootics on the dry Pacific coastal plain of Peru since at least the 1930's. However, evidence that the virus exists in the Amazon region of Peru to the east of the Andes mountains was not obtained until antibodies were found in human sera collected in 1965, and 10 strains of the virus were isolated in a forest near the city of Iquitos, Peru during February and March 1971. Eight strains came from mosquitoes and two from dead sentinel hamsters. Three hamsters exposed in forests near Iquitos developed VE virus antibodies suggesting that hamster-benign strains also exist there. Antibody tests of equine sera revealed no evidence that VE virus was actively cycling during the late 1950's or 1960's in southern coastal Peru, where equine epizootics had occurred in the 1930's and 1940's. In northern coastal Peru bordering Ecuador, antibodies were present in equine sera, presumably residual from the 1969 outbreak caused by subtype I virus, since neutralizing antibody titers were higher to subtype I virus than to subtypes III or IV. No VE virus was detected in this northern region during the dry season of 1970 by use of sentinel hamsters. The possibility is considered that VE epidemics and equine epizootics on the Pacific coast of Peru are caused by movements of virus in infected vertebrates traversing Andean passes or in infected vertebrates or mosquitoes carried in airplanes from the Amazon region.  
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  Series Volume Series Issue Edition  
  ISSN 0002-9262 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:235838 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2705  
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Author Oakenfull, E.A.; Ryder, O.A. doi  openurl
  Title Mitochondrial control region and 12S rRNA variation in Przewalski's horse (Equus przewalskii) Type Journal Article
  Year 1998 Publication Animal Genetics Abbreviated Journal Anim Genet  
  Volume 29 Issue 6 Pages 456-459  
  Keywords Animals; DNA, Mitochondrial/*genetics; Female; *Genetic Variation; Horses/*genetics; Male; Pedigree; RNA, Ribosomal/*genetics  
  Abstract (down) Variation in the control region and the 12S rRNA gene of all surviving mitochondrial lineages of Przewalski's horse was investigated. Variation is low despite the present day population being descended from 13 individuals probably representing animals from three different regions of its range. Phylogenetic comparison of these sequences, with sequences for the domestic horse, does not resolve the ancestral status of either horse.  
  Address Center for Reproduction of Endangered Species, Zoological Society of San Diego, CA 92112, USA  
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  Series Volume Series Issue Edition  
  ISSN 0268-9146 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:9883508 Approved no  
  Call Number Equine Behaviour @ team @ Serial 5040  
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Author Zentall, T.R.; Sherburne, L.M. openurl 
  Title Transfer of value from S+ to S- in a simultaneous discrimination Type Journal Article
  Year 1994 Publication Journal of experimental psychology. Animal behavior processes Abbreviated Journal J Exp Psychol Anim Behav Process  
  Volume 20 Issue 2 Pages 176-183  
  Keywords Animals; *Appetitive Behavior; Attention; Color Perception; Columbidae; *Discrimination Learning; Female; Male; Motivation; Orientation; Pattern Recognition, Visual; *Problem Solving; *Reinforcement Schedule; *Transfer (Psychology)  
  Abstract (down) Value transfer theory has been proposed to account for transitive inference effects (L. V. Fersen, C. D. L. Wynne, J. D. Delius, & J. E. R. Staddon, 1991), in which following training on 4 simultaneous discriminations (A+B-, B+C-, C+D-, D+E-) pigeons show a preference for B over D. According to this theory, some of the value of reinforcement acquired by each S+ transfers to the S-. In the transitive inference experiment, C (associated with both reward and nonreward) can transfer less value to D than A (associated only with reward) can transfer to B. Support for value transfer theory was demonstrated in 2 experiments in which an S- presented in the context of a stimulus to which responses were always reinforced (S+) was preferred over an S- presented in the context of a stimulus to which responses were sometimes reinforced (S +/-).  
  Address Department of Psychology, University of Kentucky, Lexington 40506  
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  Series Volume Series Issue Edition  
  ISSN 0097-7403 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:8189186 Approved no  
  Call Number refbase @ user @ Serial 258  
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Author Dougherty, D.M.; Lewis, P. doi  openurl
  Title Stimulus generalization, discrimination learning, and peak shift in horses Type Journal Article
  Year 1991 Publication Journal of the experimental analysis of behavior Abbreviated Journal J Exp Anal Behav  
  Volume 56 Issue 1 Pages 97-104  
  Keywords Animals; *Appetitive Behavior; Attention; *Conditioning, Operant; *Discrimination Learning; Female; *Generalization, Stimulus; Horses/*psychology; Male; *Pattern Recognition, Visual; Size Perception  
  Abstract (down) Using horses, we investigated three aspects of the stimulus control of lever-pressing behavior: stimulus generalization, discrimination learning, and peak shift. Nine solid black circles, ranging in size from 0.5 in. to 4.5 in. (1.3 cm to 11.4 cm) served as stimuli. Each horse was shaped, using successive approximations, to press a rat lever with its lip in the presence of a positive stimulus, the 2.5-in. (6.4-cm) circle. Shaping proceeded quickly and was comparable to that of other laboratory organisms. After responding was maintained on a variable-interval 30-s schedule, stimulus generalization gradients were collected from 2 horses prior to discrimination training. During discrimination training, grain followed lever presses in the presence of a positive stimulus (a 2.5-in circle) and never followed lever presses in the presence of a negative stimulus (a 1.5-in. [3.8-cm] circle). Three horses met a criterion of zero responses to the negative stimulus in fewer than 15 sessions. Horses given stimulus generalization testing prior to discrimination training produced symmetrical gradients; horses given discrimination training prior to generalization testing produced asymmetrical gradients. The peak of these gradients shifted away from the negative stimulus. These results are consistent with discrimination, stimulus generalization, and peak-shift phenomena observed in other organisms.  
  Address Department of Psychology, Ohio University, Athens 45701  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-5002 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:1940765 Approved no  
  Call Number Serial 1764  
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Author Dougherty, D.M.; Lewis, P. doi  openurl
  Title Generalization of a tactile stimulus in horses Type Journal Article
  Year 1993 Publication Journal of the Experimental Analysis of Behavior Abbreviated Journal J Exp Anal Behav  
  Volume 59 Issue 3 Pages 521-528  
  Keywords Animals; Behavior, Animal; Female; *Horses; Male; Reinforcement (Psychology); *Touch  
  Abstract (down) Using horses, we investigated the control of operant behavior by a tactile stimulus (the training stimulus) and the generalization of behavior to six other similar test stimuli. In a stall, the experimenters mounted a response panel in the doorway. Located on this panel were a response lever and a grain dispenser. The experimenters secured a tactile-stimulus belt to the horse's back. The stimulus belt was constructed by mounting seven solenoids along a piece of burlap in a manner that allowed each to provide the delivery of a tactile stimulus, a repetitive light tapping, at different locations (spaced 10.0 cm apart) along the horse's back. Two preliminary steps were necessary before generalization testing: training a measurable response (lip pressing) and training on several reinforcement schedules in the presence of a training stimulus (tapping by one of the solenoids). We then gave each horse two generalization test sessions. Results indicated that the horses' behavior was effectively controlled by the training stimulus. Horses made the greatest number of responses to the training stimulus, and the tendency to respond to the other test stimuli diminished as the stimuli became farther away from the training stimulus. These findings are discussed in the context of behavioral principles and their relevance to the training of horses.  
  Address Human Behavioral Pharmacology Laboratory, University of Texas Health Science Center, Houston 77030  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-5002 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:8315368 Approved no  
  Call Number Equine Behaviour @ team @ Serial 3571  
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Author Waite, T.A. doi  openurl
  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 (down) 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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  Series Volume Series Issue Edition  
  ISSN 1435-9448 ISBN Medium  
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  Notes PMID:12461598 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2592  
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Author Owren, M.J.; Dieter, J.A.; Seyfarth, R.M.; Cheney, D.L. doi  openurl
  Title Vocalizations of rhesus (Macaca mulatta) and Japanese (M. fuscata) macaques cross-fostered between species show evidence of only limited modification Type Journal Article
  Year 1993 Publication Developmental psychobiology Abbreviated Journal Dev Psychobiol  
  Volume 26 Issue 7 Pages 389-406  
  Keywords Animals; Animals, Newborn; Behavior, Animal; Discrimination Learning; Environment; Female; *Macaca; *Macaca mulatta; Male; Sound Spectrography; *Vocalization, Animal  
  Abstract (down) Two rhesus and two Japanese macaque infants were cross-fostered between species in order to study the effects of auditory experience on vocal development. Both the cross-fostered and normally raised control subjects were observed over the first 2 years of life and their vocalizations were tape-recorded. We classified 8053 calls by ear, placed each call in one of six acoustic categories, and calculated the rates at which different call-types were used in different social contexts. Species differences were found in the use of “coo” and “gruff” vocalizations among control subjects. Japanese macaques invariably produced coos almost exclusively. In contrast, rhesus macaques produced a mixture of coos and gruffs and showed considerable interindividual variation in the relative use of one call type or the other. Cross-fostered Japanese macaques adhered to their species-typical behavior, rarely using gruffs. Cross-fostered rhesus subjects also exhibited species-typical behavior in many contexts, but in some situations produced coos and gruffs at rates that were intermediate between those shown by normally raised animals of the two species. This outcome suggests that environmentally mediated modification of vocal behavior may have occurred, but that the resulting changes were quite limited.  
  Address California Regional Primate Research Center, University of California, Davis  
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  Series Volume Series Issue Edition  
  ISSN 0012-1630 ISBN Medium  
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  Notes PMID:8270122 Approved no  
  Call Number refbase @ user @ Serial 700  
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Author Weaver, A.; de Waal, F.B.M. openurl 
  Title An index of relationship quality based on attachment theory Type Journal Article
  Year 2002 Publication Journal of comparative psychology (Washington, D.C. : 1983) Abbreviated Journal J Comp Psychol  
  Volume 116 Issue 1 Pages 93-106  
  Keywords Analysis of Variance; Animals; *Behavior, Animal; Female; Male; *Maternal Behavior; *Object Attachment; Pan troglodytes/*psychology; Pilot Projects  
  Abstract (down) Two measures are reported of the nature or quality of a mother-offspring (MO) relationship during development using brown capuchin monkeys (Cebus apella) as models. One is a qualitative classification of MO relationships as secure, resistant, or avoidant attachments. The other is an empirical ratio of relative affiliation to agonism called the MO relationship quality, or MORQ, Index. The two methods tapped similar relationship features so relationships high or low of a median split of MORQ values were heuristically labeled secure (n = 22) or insecure (n = 16), respectively. A comparison revealed extensive behavioral differences between secure and insecure MO relationships and suggested MORQ provided an objective, continuous measure of attachment security.  
  Address Yerkes Regional Primate Research Center, Emory University, USA. achweaver@att.net  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0735-7036 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:11930937 Approved no  
  Call Number refbase @ user @ Serial 183  
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Author Parr, L.A.; Hopkins, W.D.; de Waal, F.B. openurl 
  Title Haptic discrimination in capuchin monkeys (Cebus apella): evidence of manual specialization Type Journal Article
  Year 1997 Publication Neuropsychologia Abbreviated Journal Neuropsychologia  
  Volume 35 Issue 2 Pages 143-152  
  Keywords Aging/psychology; Animals; Cebus; Cues; Discrimination (Psychology)/*physiology; Female; Functional Laterality/*physiology; Male; Psychomotor Performance/physiology; Sex Characteristics; Touch/physiology  
  Abstract (down) Two experiments investigated the effects of haptic and visual discrimination on hand preference in 22 brown capuchin monkeys (Cebus apella). The percentage of left-handed subjects in Experiment 1 were 63.6%, 45.5%, and 18.2% for haptic, bipedal, and quadrupedal reaching, respectively. In Experiment 2, the haptic demands of the task were manipulated by using additional food types and another tactile medium. Left-hand preferences were further strengthened when reaching into water compared to pineshavings in Experiment 1. Reaching with no tactile interference resulted in equal numbers of lateralized and nonlateralized subjects. These results show that when reaching demands the use of haptic cues, as opposed to visual ones, monkeys shift towards greater left hand use. This is consistent with what is known about right hemisphere superiority for haptic discrimination in humans.  
  Address Division of Psychobiology, Yerkes Regional Primate Research Center, Atlanta, GA 30329, USA. parr@rmy.-emory.edu  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0028-3932 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:9025118 Approved no  
  Call Number refbase @ user @ Serial 201  
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Author Fiset, S.; Beaulieu, C.; Landry, F. doi  openurl
  Title Duration of dogs' (Canis familiaris) working memory in search for disappearing objects Type Journal Article
  Year 2003 Publication Animal Cognition Abbreviated Journal Anim. Cogn.  
  Volume 6 Issue 1 Pages 1-10  
  Keywords Animals; Dogs/*psychology; *Exploratory Behavior; Female; Male; *Memory; Visual Perception  
  Abstract (down) Two experiments explored the duration of dogs' working memory in an object permanence task: a delay was introduced between the disappearance of a moving object behind a box and the beginning of the search by the animal. In experiment 1, the dogs were tested with retention intervals of 0, 10, 30, and 60 s. Results revealed that the dogs' accuracy declined as a function of the length of the retention interval but remained above chance for each retention interval. In experiment 2, with new subjects, longer retention intervals (0, 30, 60, 120, and 240 s) were presented to the dogs. Results replicated findings from experiment 1 and revealed that the dogs' accuracy remained higher than chance level with delays up to 240 s. In both experiments, the analysis of errors also showed that the dogs searched as a function of the proximity of the target box and were not subject to intertrial proactive interference. In the discussion, we explore different alternatives to explain why dogs' search behaviour for hidden objects decreased as a function of the retention intervals.  
  Address Secteur Sciences Humaines, Universite de Moncton, Campus d'Edmundston, E3V 2S8, Edmundston, New Brunswick, Canada. sfiset@umce.ca  
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  Series Volume Series Issue Edition  
  ISSN 1435-9448 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:12658530 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2586  
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