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Author Cameron, E.Z. doi  openurl
  Title Facultative adjustment of mammalian sex ratios in support of the Trivers-Willard hypothesis: evidence for a mechanism Type Journal Article
  Year 2004 Publication Proceedings. Biological sciences / The Royal Society Abbreviated Journal Proc Biol Sci  
  Volume 271 Issue 1549 Pages (down) 1723-1728  
  Keywords Age Factors; Animals; Body Constitution; *Evolution; Female; Glucose/metabolism/physiology; Litter Size; Male; Mammals/*physiology; *Models, Biological; Reproduction/physiology; Seasons; Sex Factors; *Sex Ratio; Time Factors  
  Abstract Evolutionary theory predicts that mothers of different condition should adjust the birth sex ratio of their offspring in relation to future reproductive benefits. Published studies addressing variation in mammalian sex ratios have produced surprisingly contradictory results. Explaining the source of such variation has been a challenge for sex-ratio theory, not least because no mechanism for sex-ratio adjustment is known. I conducted a meta-analysis of previous mammalian sex-ratio studies to determine if there are any overall patterns in sex-ratio variation. The contradictory nature of previous results was confirmed. However, studies that investigated indices of condition around conception show almost unanimous support for the prediction that mothers in good condition bias their litters towards sons. Recent research on the role of glucose in reproductive functioning have shown that excess glucose favours the development of male blastocysts, providing a potential mechanism for sex-ratio variation in relation to maternal condition around conception. Furthermore, many of the conflicting results from studies on sex-ratio adjustment would be explained if glucose levels in utero during early cell division contributed to the determination of offspring sex ratios.  
  Address Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria 0002, South Africa. ezcameron@zoology.up.ac.za  
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  Series Volume Series Issue Edition  
  ISSN 0962-8452 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15306293 Approved no  
  Call Number refbase @ user @ Serial 413  
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Author Hall, C.A.; Cassaday, H.J.; Derrington, A.M. openurl 
  Title The effect of stimulus height on visual discrimination in horses Type Journal Article
  Year 2003 Publication Journal of Animal Science Abbreviated Journal J. Anim Sci.  
  Volume 81 Issue 7 Pages (down) 1715-1720  
  Keywords Animals; *Discrimination Learning/physiology; Female; Horses/physiology/*psychology; Male; Orientation; *Photic Stimulation; Vision/*physiology  
  Abstract This study investigated the effect of stimulus height on the ability of horses to learn a simple visual discrimination task. Eight horses were trained to perform a two-choice, black/white discrimination with stimuli presented at one of two heights: ground level or at a height of 70 cm from the ground. The height at which the stimuli were presented was alternated from one session to the next. All trials within a single session were presented at the same height. The criterion for learning was four consecutive sessions of 70% correct responses. Performance was found to be better when stimuli were presented at ground level with respect to the number of trials taken to reach the criterion (P < 0.05), percentage of correct first choices (P < 0.01), and repeated errors made (P < 0.01). Thus, training horses to carry out tasks of visual discrimination could be enhanced by placing the stimuli on the ground. In addition, the results of the present study suggest that the visual appearance of ground surfaces is an important factor in both horse management and training.  
  Address School of Land-based Studies, Nottingham Trent University, Brackenhurst College Campus, Southwell, Nottinghamshire, England NG25 0QF. carol.hall@ntu.ac.uk  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-8812 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:12854807 Approved no  
  Call Number refbase @ user @ Serial 835  
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Author Krebs, J.R.; Clayton, N.S.; Hampton, R.R.; Shettleworth, S.J. openurl 
  Title Effects of photoperiod on food-storing and the hippocampus in birds Type Journal Article
  Year 1995 Publication Neuroreport Abbreviated Journal Neuroreport  
  Volume 6 Issue 12 Pages (down) 1701-1704  
  Keywords Animals; Birds; Eating/*physiology; Female; Hippocampus/*physiology; Light; Male; *Photoperiod; Seasons; Telencephalon/physiology; Time Factors  
  Abstract Birds that store food have a relatively large hippocampus compared to non-storing species. The hippocampus shows seasonal differences in neurogenesis and volume in black-capped chikadees (Parus atricapillus) taken from the wild at different times of year. We compared hippocampal volumes in black-capped chickadees captured at the same time but differing in food-storing behaviour because of manipulations of photoperiod in the laboratory. Differences in food-storing behaviour were not accompanied by differences in the volume of the hippocampus. Hippocampal volumes also did not differ between two groups of a non-food-storing control species, house sparrows (Passer domesticus), exposed to the same conditions as the chickadees.  
  Address Edward Grey Institute of Field Ornithology, Department of Zoology, Oxford, UK  
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  Series Volume Series Issue Edition  
  ISSN 0959-4965 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:8527745 Approved no  
  Call Number refbase @ user @ Serial 378  
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Author Grogan, E.H.; McDonnell, S.M. openurl 
  Title Behavioral responses to two intranasal vaccine applicators in horses and ponies Type
  Year 2005 Publication Journal of the American Veterinary Medical Association Abbreviated Journal J Am Vet Med Assoc  
  Volume 226 Issue 10 Pages (down) 1689-1693  
  Keywords Administration, Intranasal; Animals; *Behavior, Animal; Female; Horses/physiology/*psychology; Immunization/instrumentation/methods/*veterinary; Male; Patient Compliance/psychology; Physical Examination/psychology/*veterinary; Vaccines/*administration & dosage; Videotape Recording  
  Abstract OBJECTIVE: To evaluate behavioral compliance of horses and ponies with simulated intranasal vaccination and assess development of generalized aversion to veterinary manipulations. DESIGN: Clinical trial. ANIMALS: 28 light horse mares, 3 pony geldings, 2 light horse stallions, and 3 pony stallions that had a history of compliance with veterinary procedures. PROCEDURE: Behavioral compliance with 2 intranasal vaccine applicators was assessed. Compliance with standard physical examination procedures was assessed before and after a single experience with either of the applicators or a control manipulation to evaluate development of generalized aversion to veterinary manipulation. RESULTS: In all 30 horses, simulated intranasal vaccination or the control manipulation could be performed without problematic avoidance behavior, and simulated intranasal vaccination did not have any significant effect on duration of or compliance with a standardized physical examination that included manipulation of the ears, nose, and mouth. Results were similar for the 2 intranasal vaccine applicators, and no difference in compliance was seen between horses in which warm versus cold applicators were used. For 3 of the 6 ponies, substantial avoidance behavior was observed in association with simulated intranasal vaccination, and compliance with physical examination procedures decreased after simulated intranasal vaccination. CONCLUSIONS AND CLINICAL RELEVANCE: Although some compliance problems were seen with ponies, neither problems with compliance with simulated intranasal vaccination nor adverse effects on subsequent physical examination were identified in any of the horses. Further study is needed to understand factors involved in practitioner reports of aversion developing in association with intranasal vaccination.  
  Address Equine Behavior Laboratory, New Bolton Center, School of Veterinary Medicine, University of Pennsylvania, Kennett Square, PA 19348, USA  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-1488 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15906570 Approved no  
  Call Number Serial 1890  
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Author Seyfarth, R.M.; Cheney, D.L. openurl 
  Title The acoustic features of vervet monkey grunts Type Journal Article
  Year 1984 Publication The Journal of the Acoustical Society of America Abbreviated Journal J Acoust Soc Am  
  Volume 75 Issue 5 Pages (down) 1623-1628  
  Keywords *Acoustics; Animals; Auditory Perception; Cercopithecus/*physiology; Cercopithecus aethiops/*physiology; Cues; Dominance-Subordination; Female; Male; Social Behavior; Sound Spectrography; *Vocalization, Animal  
  Abstract East African vervet monkeys give short (125 ms), harsh-sounding grunts to each other in a variety of social situations: when approaching a dominant or subordinate member of their group, when moving into a new area of their range, or upon seeing another group. Although all these vocalizations sound similar to humans, field playback experiments have shown that the monkeys distinguish at least four different calls. Acoustic analysis reveals that grunts have an aperiodic F0, at roughly 240 Hz. Most grunts exhibit a spectral peak close to this irregular F0. Grunts may also contain a second, rising or falling frequency peak, between 550 and 900 Hz. The location and changes in these two frequency peaks are the cues most likely to be used by vervets when distinguishing different grunt types.  
  Address  
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  Series Volume Series Issue Edition  
  ISSN 0001-4966 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:6736426 Approved no  
  Call Number refbase @ user @ Serial 703  
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Author McDonnell, S.M.; Freeman, D.A.; Cymbaluk, N.F.; Schott, H.C. 2nd; Hinchcliff, K.; Kyle, B. openurl 
  Title Behavior of stabled horses provided continuous or intermittent access to drinking water Type Journal Article
  Year 1999 Publication American Journal of Veterinary Research Abbreviated Journal Am J Vet Res  
  Volume 60 Issue 11 Pages (down) 1451-1456  
  Keywords Aggression; Animal Husbandry; Animals; Behavior, Animal/*physiology; Drinking Behavior; Feeding Behavior; Female; Horses/*physiology/*psychology; Housing, Animal; Pregnancy; Pregnancy, Animal/physiology/*psychology; Social Behavior; Videotape Recording; *Water Supply  
  Abstract OBJECTIVE: To compare quantitative measures and clinical assessments of behavior as an indication of psychologic well-being of stabled horses provided drinking water continuously or via 1 of 3 intermittent delivery systems. ANIMALS: 22 Quarter Horse (QH) or QH-crossbred mares and 17 Belgian or Belgian-crossbred mares (study 1) and 24 QH or QH-crossbred mares and 18 Belgian or Belgian-crossbred mares (study 2). PROCEDURE: Stabled horses were provided water continuously or via 1 of 3 intermittent water delivery systems in 2 study periods during a 2-year period. Continuous 24-hour videotaped samples were used to compare quantitative measures and clinical assessments of behavior among groups provided water by the various water delivery systems. RESULTS: All horses had clinically normal behavior. Significant differences in well being were not detected among groups provided water by the various delivery systems. CONCLUSIONS AND CLINICAL RELEVANCE: Various continuous and intermittent water delivery systems can provide adequately for the psychologic well-being of stabled horses.  
  Address New Bolton Center, School of Veterinary Medicine, University of Pennsylvania, Kennett Square 19348, USA  
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  Series Volume Series Issue Edition  
  ISSN 0002-9645 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:10566826 Approved no  
  Call Number refbase @ user @ Serial 1928  
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Author Hernandez, J.; Hawkins, D.L. openurl 
  Title Training failure among yearling horses Type Journal Article
  Year 2001 Publication American Journal of Veterinary Research Abbreviated Journal Am J Vet Res  
  Volume 62 Issue 9 Pages (down) 1418-1422  
  Keywords Animals; Female; Florida; Horses/*physiology; Lameness, Animal/*economics; Male; Physical Conditioning, Animal/adverse effects/economics; Respiratory Tract Diseases/economics/*veterinary; Statistics, Nonparametric  
  Abstract OBJECTIVE: To compare financial returns between pinhooked yearling horses (ie, bought and trained for approximately 5 months with the goal of selling the horse at “2-year-olds in training” sales) that had mild or severe training failure and horses that had planned versus nonplanned training failure. ANIMALS: 40 Thoroughbred pinhooked yearling horses. PROCEDURE: During the period from September 1998 through and April 1999, 20 horses had mild training failure (1 to 11 days lost), and 20 horses had severe training failure (13 to 108 days lost). Horses were assigned to these 2 groups on the basis of frequency distribution (median) of days lost during training. Horses were also categorized on the basis of type of training failure (planned vs nonplanned training failure). The outcome of primary interest was financial return. Median financial returns were compared among groups by use of the Mann-Whitney U test. RESULTS: Median financial returns for horses that had severe training failure ($1,000) were significantly different, compared with horses that had mild training failure ($24,000). Analysis of results also indicated that median returns were significantly different among horses that had planned training failure (-$2,000; eg, horses with radiographic abnormalities detected during routine prepurchase examinations that required surgical treatment, resulting in days lost during training), compared with horses that did not ($10,000). CONCLUSIONS AND CLINICAL RELEVANCE: Training failure has an economic impact on revenues in pinhooked yearling horses. Lameness, planned training failure, respiratory disease, and ringworm were common and important causes of training failure.  
  Address Department of Large Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville 32610-0136, USA  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 0002-9645 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:11560271 Approved no  
  Call Number Equine Behaviour @ team @ Serial 4051  
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Author Mouritsen, K.N. openurl 
  Title Hitch-hiking parasite: a dark horse may be the real rider Type Journal Article
  Year 2001 Publication International Journal for Parasitology Abbreviated Journal Int J Parasitol  
  Volume 31 Issue 13 Pages (down) 1417-1420  
  Keywords Animals; *Behavior, Animal; Ecology; Host-Parasite Relations; Snails/*parasitology; Trematoda/growth & development/*physiology; Trematode Infections/transmission  
  Abstract Many parasites engaged in complex life cycles manipulate their hosts in a way that facilitates transmission between hosts. Recently, a new category of parasites (hitch-hikers) has been identified that seem to exploit the manipulating effort of other parasites with similar life cycle by preferentially infecting hosts already manipulated. Thomas et al. (Evolution 51 (1997) 1316) showed that the digenean trematodes Microphallus papillorobustus (the manipulator) and Maritrema subdolum (the hitch-hiker) were positively associated in field samples of gammarid amphipods (the intermediate host), and that the behaviour of Maritrema subdolum rendered it more likely to infect manipulated amphipods than those uninfected by M. papillorobustus. Here I provide experimental evidence demonstrating that M. subdolum is unlikely to be a hitch-hiker in the mentioned system, whereas the lucky candidate rather is the closely related but little known species, Microphallidae sp. no. 15 (Parassitologia 22 (1980) 1). As opposed to the latter species, Maritrema subdolum does not express the appropriate cercarial behaviour for hitch-hiking.  
  Address Department of Marine Ecology, Institute of Biological Sciences, University of Aarhus, Finlandsgade 14, DK-8200 Aarhus N, Denmark. kim.mouritsen@stonebow.otago.ac.nz  
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  Series Volume Series Issue Edition  
  ISSN 0020-7519 ISBN Medium  
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  Notes PMID:11595227 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2645  
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Author Naylor, J.M.; Poirier, K.L.; Hamilton, D.L.; Dowling, P.M. openurl 
  Title The effects of feeding and fasting on gastrointestinal sounds in adult horses Type Journal Article
  Year 2006 Publication Journal of Veterinary Internal Medicine / American College of Veterinary Internal Medicine Abbreviated Journal J Vet Intern Med  
  Volume 20 Issue 6 Pages (down) 1408-1413  
  Keywords Animals; Auscultation/methods/*veterinary; *Digestive Physiology; Fasting/*physiology; Gastrointestinal Motility/physiology; Gastrointestinal Transit/physiology; Horses/*physiology; Postprandial Period/*physiology; Sound  
  Abstract The effect of changes in feed intake on auscultatable gastrointestinal sounds has not been systematically studied. Disagreement also is present in the literature about variation in sounds according to the quadrant of auscultation. Gastrointestinal sounds were recorded over the center of the left dorsal, left ventral, right ventral, and right dorsal quadrants and over the middle of the right abdominal flank. During 24 hours (n = 4) or 48 hours (n = 5) of fasting, there was a reduction in the intensity of gastrointestinal sounds as assessed by analysis of sound recordings. There was also a reduction in the number of mixing-like and propulsive-like sounds heard by 2 blinded observers. After refeeding, there was a marked increase in sound. Sound intensity varied among abdominal quadrants, but blinded observers did not notice significant differences in the number of mixing-like sounds. The left dorsal quadrant was quieter than others during fasting and refeeding. The right ventral quadrant appeared to be least affected by fasting, and sounds were louder over the right ventral and right middle quadrants than over the others. The blinded observers' perceptions of sound correlated poorly with one another and with objective measures of sound intensity. This experiment demonstrates the effectiveness of computerized analysis of abdominal sound in detecting a reduction in the intensity of gastrointestinal sounds during fasting and their return during refeeding. The left dorsal quadrant was quieter than other quadrants, likely because of its position over the small colon. There was considerable observer variation in the number of intestinal sounds heard.  
  Address Department of Clinical Sciences, Ross University School of Veterinary Medicine, Basseterre, St Kitts, West Indies. jnaylor@rossvet.edu.kn  
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  ISSN 0891-6640 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:17186858 Approved no  
  Call Number Serial 1844  
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Author Moses, S.N.; Villate, C.; Ryan, J.D. doi  openurl
  Title An investigation of learning strategy supporting transitive inference performance in humans compared to other species Type Journal Article
  Year 2006 Publication Neuropsychologia Abbreviated Journal Neuropsychologia  
  Volume 44 Issue 8 Pages (down) 1370-1387  
  Keywords Adult; Analysis of Variance; Association Learning/*physiology; *Cognition; *Concept Formation; Female; Humans; *Logic; Male; Pattern Recognition, Visual/physiology; Photic Stimulation/methods; Reaction Time/physiology  
  Abstract Generalizations about neural function are often drawn from non-human animal models to human cognition, however, the assumption of cross-species conservation may sometimes be invalid. Humans may use different strategies mediated by alternative structures, or similar structures may operate differently within the context of the human brain. The transitive inference problem, considered a hallmark of logical reasoning, can be solved by non-human species via associative learning rather than logic. We tested whether humans use similar strategies to other species for transitive inference. Results are crucial for evaluating the validity of widely accepted assumptions of similar neural substrates underlying performance in humans and other animals. Here we show that successful transitive inference in humans is unrelated to use of associative learning strategies and is associated with ability to report the hierarchical relationship among stimuli. Our work stipulates that cross-species generalizations must be interpreted cautiously, since performance on the same task may be mediated by different strategies and/or neural systems.  
  Address Rotman Research Institute, Baycrest Centre for Geriatric Care, Toronto, Canada. smoses@rotman-baycrest.on.ca  
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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:16503340 Approved no  
  Call Number refbase @ user @ Serial 153  
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