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Author Ahrendt, L.P.; Labouriau, R.; Malmkvist, J.; Nicol, C.J.; Christensen, J.W. url  doi
openurl 
  Title Development of a standard test to assess negative reinforcement learning in horses Type Journal Article
  Year 2015 Publication Applied Animal Behaviour Science Abbreviated Journal Appl. Anim. Behav. Sci.  
  Volume 169 Issue Pages 38-42  
  Keywords Algometry; Horse behaviour; Learning performance; Operant conditioning; Pressure-release; Horse training  
  Abstract Most horses are trained by negative reinforcement. Currently, however, no standardised test for evaluating horses' negative reinforcement learning ability is available. The aim of this study was to develop an objective test to investigate negative reinforcement learning in horses. Twenty-four Icelandic horses (3 years old) were included in this study. The horses were tested in a pressure-release task on three separate days with 10, 7 and 5 trials on each side, respectively. Each trial consisted of pressure being applied on the hindquarter with an algometer. The force of the pressure was increased until the horse moved laterally away from the point of pressure. There was a significant decrease in required force over trials on the first test day (P<0.001), but not the second and third day. The intercepts on days 2 and 3 differed significantly from day 1 (P<0.001), but not each other. Significantly stronger force was required on the right side compared to the left (P<0.001), but there was no difference between first and second side tested (P=0.56). Individual performance was evaluated by median-force and the change in force over trials on the first test day. These two measures may explain different characteristics of negative reinforcement learning. In conclusion, this study presents a novel, standardised test for evaluating negative reinforcement learning ability in horses.  
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  ISSN (up) 0168-1591 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 6650  
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Author Sufit, E.; Houpt, K.A.; Sweeting, M. openurl 
  Title Physiological stimuli of thirst and drinking patterns in ponies Type Journal Article
  Year 1985 Publication Equine veterinary journal Abbreviated Journal Equine Vet J  
  Volume 17 Issue 1 Pages 12-16  
  Keywords Animals; Blood Proteins/analysis; Drinking Behavior/drug effects/*physiology; Furosemide/pharmacology; Horses/*physiology; Male; Osmolar Concentration; Osmotic Pressure; Sodium Chloride/pharmacology; Thirst/drug effects/*physiology; Time Factors; Water Deprivation/physiology  
  Abstract The stimuli that elicit thirst were studied in four ponies. Nineteen hours of water deprivation produced an increase in plasma protein from 67 +/- 0.1 g/litre to 72 +/- 2 g/litre, a mean (+/- se) increase in plasma sodium from 139 +/- 3 to 145 +/- 2 mmol/litre and an increase in plasma osmolality from 297 +/- 1 to 306 +/- 2 mosmol/litre. Undeprived ponies drank 1.5 +/- 0.9 kg/30 mins; 19 h deprived ponies drank 10.2 +/- 2.5 kg/30 mins and corrected the deficits in plasma protein, plasma sodium and plasma osmolality as well as compensating for the water they would have drunk during the deprivation period. In order to determine if an increase in plasma osmolality would stimulate thirst, 250 ml of 15 per cent sodium chloride was infused intravenously. The ponies drank when osmolality increased 3 per cent and when plasma sodium rose from 136 +/- 3 mmol/litre to 143 +/- 3 mmol/litre. Ponies infused with 15 per cent sodium chloride drank 2.9 +/- 0.7 kg; those infused with 0.9 per cent sodium chloride drank 0.7 +/- 0.5 kg. In order to determine if a decrease in plasma volume would stimulate thirst, ponies were injected with 1 or 2 mg/kg bodyweight (bwt) frusemide. Plasma protein rose from 68 +/- 2 g/litre pre-injection to 75 +/- 2 g/litre 1 h after 1 mg/kg bwt frusemide and to 81 +/- 1 g/litre 1 h after 2 mg/kg bwt frusemide.(ABSTRACT TRUNCATED AT 250 WORDS)  
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  ISSN (up) 0425-1644 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:3979367 Approved no  
  Call Number refbase @ user @ Serial 56  
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Author Fruehwirth, B.; Peham, C.; Scheidl, M.; Schobesberger, H. openurl 
  Title Evaluation of pressure distribution under an English saddle at walk, trot and canter Type Journal Article
  Year 2004 Publication Equine Veterinary Journal Abbreviated Journal Equine Vet J  
  Volume 36 Issue 8 Pages 754-757  
  Keywords Animals; Back/*physiology; Biomechanics; Body Weight/physiology; Exercise Test/veterinary; Gait/*physiology; Horses/*physiology; Humans; Locomotion/*physiology; Pressure  
  Abstract REASONS FOR PERFORMING STUDY: Basic information about the influence of a rider on the equine back is currently lacking. HYPOTHESIS: That pressure distribution under a saddle is different between the walk, trot and canter. METHODS: Twelve horses without clinical signs of back pain were ridden. At least 6 motion cycles at walk, trot and canter were measured kinematically. Using a saddle pad, the pressure distribution was recorded. The maximum overall force (MOF) and centre of pressure (COP) were calculated. The range of back movement was determined from a marker placed on the withers. RESULTS: MOF and COP showed a consistent time pattern in each gait. MOF was 12.1 +/- 1.2 and 243 +/- 4.6 N/kg at walk and trot, respectively, in the ridden horse. In the unridden horse MOF was 172.7 +/- 11.8 N (walk) and 302.4 +/- 33.9 N (trot). At ridden canter, MOF was 27.2 +/- 4.4 N/kg. The range of motion of the back of the ridden horse was significantly lower compared to the unridden, saddled horse. CONCLUSIONS AND POTENTIAL RELEVANCE: Analyses may help quantitative and objective evaluation of the interaction between rider and horse as mediated through the saddle. The information presented is therefore of importance to riders, saddlers and equine clinicians. With the technique used in this study, style, skill and training level of different riders can be quantified, which would give the opportunity to detect potentially harmful influences and create opportunities for improvement.  
  Address Movement Science Group, Department V, Clinic of Orthopaedics in Ungulates, University of Veterinary Medicine, Vienna, Austria  
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  ISSN (up) 0425-1644 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15656510 Approved no  
  Call Number Equine Behaviour @ team @ Serial 4041  
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Author Grubb, T.L.; Foreman, J.H.; Benson, G.J.; Thurmon, J.C.; Tranquilli, W.J.; Constable, P.D.; Olson, W.O.; Davis, L.E. openurl 
  Title Hemodynamic effects of calcium gluconate administered to conscious horses Type Journal Article
  Year 1996 Publication Journal of veterinary internal medicine / American College of Veterinary Internal Medicine Abbreviated Journal J Vet Intern Med  
  Volume 10 Issue 6 Pages 401-404  
  Keywords Animals; Blood Pressure/drug effects/physiology; Calcium/blood; Calcium Gluconate/administration & dosage/*pharmacology; Cardiac Output/drug effects/physiology; Consciousness/*physiology; Dose-Response Relationship, Drug; Female; Heart Rate/drug effects/physiology; Hemodynamic Processes/*drug effects/physiology; Horses/blood/*physiology; Infusions, Intravenous; Male; Myocardial Contraction/drug effects/physiology; Respiration/drug effects/physiology; Stroke Volume/drug effects/physiology; Time Factors  
  Abstract Calcium gluconate was administered to conscious horses at 3 different rates (0.1, 0.2, and 0.4 mg/kg/min for 15 minutes each). Serum calcium concentrations and parameters of cardiovascular function were evaluated. All 3 calcium administration rates caused marked increases in both ionized and total calcium concentrations, cardiac index, stroke index, and cardiac contractility (dP/dtmax). Mean arterial pressure and right atrial pressure were unchanged; heart rate decreased markedly during calcium administration. Ionized calcium concentration remained between 54% and 57% of total calcium concentration throughout the study. We conclude that calcium gluconate can safely be administered to conscious horses at 0.1 to 0.4 mg/kg/min and that administration will result in improved cardiac function.  
  Address Department of Veterinary Clinical Medicine, University of Illinois at Urbana-Champaign, USA  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN (up) 0891-6640 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:8947873 Approved no  
  Call Number refbase @ user @ Serial 97  
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Author Nicol, C.J.; Adachi, M.; Akiyama, T.E.; Gonzalez, F.J. doi  openurl
  Title PPARgamma in endothelial cells influences high fat diet-induced hypertension Type Journal Article
  Year 2005 Publication American journal of hypertension : journal of the American Society of Hypertension Abbreviated Journal Am J Hypertens  
  Volume 18 Issue 4 Pt 1 Pages 549-556  
  Keywords Administration, Oral; Animals; Antihypertensive Agents/pharmacology; Blood Pressure/drug effects; Diabetes Mellitus, Type 2/physiopathology; Dietary Fats/*administration & dosage/pharmacology; Dose-Response Relationship, Drug; Endothelial Cells/*metabolism; Female; Heart Rate/drug effects; Hypertension/*etiology; Ligands; Male; Mice; Mice, Knockout; PPAR gamma/*metabolism; Sodium Chloride/administration & dosage/pharmacology; Thiazolidinediones/pharmacology  
  Abstract BACKGROUND: Peroxisome proliferator-activated receptor gamma (PPARgamma) ligands improve human hypertension. However, the mechanism and site of this effect remains unknown, confounded by PPARgamma expression in many cell types, including endothelial cells (ECs). METHODS: To evaluate the vascular role of PPARgamma we used a conditional null mouse model. Specific disruption of PPARgamma in ECs was created by crossing Tie2-Cre+ transgenic (T2T+) and PPARgamma-floxed (fl/fl) mice to generate PPARgamma (fl/fl)T2T+ (PPARgamma E-null) mice. Conscious 8- to 12-week-old congenic PPARgamma (fl/fl)Cre- (wild type) and PPARgamma E-null mice were examined for changes in systolic blood pressure (BP) and heart rate (HR), untreated, after 2 months of salt-loading (drinking water), and after treatment for 3 months with high fat (HF) diet alone or supplemented during the last 2 weeks with rosiglitazone (3 mg/kg/d). RESULTS: Untreated PPARgamma E-nulls were phenotypically indistinguishable from wild-type littermates. However, compared to similarly treated wild types, HF-treated PPARgamma E-nulls had significantly elevated systolic BP not seen after normal diet or salt-loading. Despite sex-dependent baseline differences, salt-loaded and HF-treated PPARgamma E-nulls of either sex had significantly elevated HR versus wild types. Interestingly, rosiglitazone improved serum insulin levels, but not HF diet-induced hypertension, in PPARgamma E-null mice. CONCLUSIONS: These results suggest that PPARgamma in ECs not only is an important regulator of hypertension and HR under stressed conditions mimicking those arising in type 2 diabetics, but also mediates the antihypertensive effects of rosiglitazone. These data add evidence supporting a beneficial role for PPARgamma-specific ligands in the treatment of hypertension, and suggest therapeutic strategies targeting ECs may prove useful.  
  Address Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA  
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  Language English Summary Language Original Title  
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  ISSN (up) 0895-7061 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15831367 Approved no  
  Call Number refbase @ user @ Serial 69  
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Author Keay, J.M.; Singh, J.; Gaunt, M.C.; Kaur, T. doi  openurl
  Title Fecal glucocorticoids and their metabolites as indicators of stress in various mammalian species: a literature review Type Journal Article
  Year 2006 Publication Journal of zoo and wildlife medicine : official publication of the American Association of Zoo Veterinarians Abbreviated Journal J Zoo Wildl Med  
  Volume 37 Issue 3 Pages 234-244  
  Keywords Animals; *Animals, Wild/metabolism; Chromatography, High Pressure Liquid/methods/veterinary; Circadian Rhythm; Conservation of Natural Resources; *Ecosystem; Feces/*chemistry; Glucocorticoids/*analysis/metabolism; Humans; Seasons; Species Specificity; Specimen Handling/methods/veterinary; Stress, Psychological/*metabolism  
  Abstract Conservation medicine is a discipline in which researchers and conservationists study and respond to the dynamic interplay between animals, humans, and the environment. From a wildlife perspective, animal species are encountering stressors from numerous sources. With the rapidly increasing human population, a corresponding increased demand for food, fuel, and shelter; habitat destruction; and increased competition for natural resources, the health and well-being of wild animal populations is increasingly at risk of disease and endangerment. Scientific data are needed to measure the impact that human encroachment is having on wildlife. Nonbiased biometric data provide a means to measure the amount of stress being imposed on animals from humans, the environment, and other animals. The stress response in animals functions via glucocorticoid metabolism and is regulated by the hypothalamic-pituitary-adrenal axis. Fecal glucocorticoids, in particular, may be an extremely useful biometric test, since sample collection is noninvasive to subjects and, therefore, does not introduce other variables that may alter assay results. For this reason, many researchers and conservationists have begun to use fecal glucocorticoids as a means to measure stress in various animal species. This review article summarizes the literature on many studies in which fecal glucocorticoids and their metabolites have been used to assess stress levels in various mammalian species. Variations between studies are the main focus of this review. Collection methods, storage conditions, shipping procedures, and laboratory techniques utilized by different researchers are discussed.  
  Address Department of Biomedical Sciences and Pathobiology, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Tech, 0442 Duck Pond Drive, Blacksburg, Virginia 24061, USA  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN (up) 1042-7260 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:17319120 Approved no  
  Call Number refbase @ user @ Serial 616  
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Author de Cocq, P.; van Weeren, P.R.; Back, W. url  doi
openurl 
  Title Saddle pressure measuring: Validity, reliability and power to discriminate between different saddle-fits Type Journal Article
  Year 2006 Publication The Veterinary Journal Abbreviated Journal  
  Volume 172 Issue 2 Pages 265-273  
  Keywords Horse; Pressure; Back; Saddle; Saddle-fit  
  Abstract Saddle-fit is recognised as an important factor in the pathogenesis of back problems in horses and is empirically being evaluated by pressure measurements in clinical practice, although not much is known about the validity, reliability and usability of these devices in the equine field. This study was conducted to assess critically a pressure measurement system marketed for evaluating saddle fit. Validity was tested by calculating the correlation coefficient between total measured pressure and the weight of 28 different riders. Reliability and discriminative power with respect to different saddle fitting methods were evaluated in a highly standardised, paired measurement set-up in which saddle-fit was quantified by air-pressure values inside the panels of the saddle. Total pressures under the saddle correlated well with riders’ weight. A large increase in over-day sensor variation was found. Within trial intra-class correlation coefficients (ICCs) were excellent, but the between trial ICCs varied from poor to excellent and the variation in total pressure was high. In saddles in which the fit was adjusted to individual asymmetries of the horse, the pressure measurement device was able to detect correctly air-pressure differences between the two panels in the back area of the saddle, but not in the front area. The device yielded valid results, but was only reliable in highly standardised conditions. The results question the indiscriminate use of current saddle pressure measurement devices for the quantitative assessment of saddle-fit under practical conditions and suggest that further technical improvement may be necessary.  
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  Series Volume Series Issue Edition  
  ISSN (up) 1090-0233 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 5819  
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Author Belock, B.; Kaiser, L.J.; Lavagnino, M.; Clayton, H.M. url  doi
openurl 
  Title Comparison of pressure distribution under a conventional saddle and a treeless saddle at sitting trot Type Journal Article
  Year 2012 Publication The Veterinary Journal Abbreviated Journal  
  Volume 193 Issue 1 Pages 87-91  
  Keywords Horse; Rider; Equitation; Tack; Electronic pressure mat  
  Abstract It can be a challenge to find a conventional saddle that is a good fit for both horse and rider. An increasing number of riders are purchasing treeless saddles because they are thought to fit a wider range of equine back shapes, but there is only limited research to support this theory. The objective of this study was to compare the total force and pressure distribution patterns on the horse’s back with conventional and treeless saddles. The experimental hypotheses were that the conventional saddle would distribute the force over a larger area with lower mean and maximal pressures than the treeless saddle. Eight horses were ridden by a single rider at sitting trot with conventional and treeless saddles. An electronic pressure mat measured total force, area of saddle contact, maximal pressure and area with mean pressure >11 kPa for 10 strides with each saddle. Univariate ANOVA (P < 0.05) was used to detect differences between saddles. Compared with the treeless saddle, the conventional saddle distributed the rider’s bodyweight over a larger area, had lower mean and maximal pressures and fewer sensors recording mean pressure >11 kPa. These findings suggested that the saddle tree was effective in distributing the weight of the saddle and rider over a larger area and in avoiding localized areas of force concentration.  
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  Series Volume Series Issue Edition  
  ISSN (up) 1090-0233 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 5821  
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Author Guo, G.L.; Moffit, J.S.; Nicol, C.J.; Ward, J.M.; Aleksunes, L.A.; Slitt, A.L.; Kliewer, S.A.; Manautou, J.E.; Gonzalez, F.J. doi  openurl
  Title Enhanced acetaminophen toxicity by activation of the pregnane X receptor Type Journal Article
  Year 2004 Publication Toxicological sciences : an official journal of the Society of Toxicology Abbreviated Journal Toxicol Sci  
  Volume 82 Issue 2 Pages 374-380  
  Keywords Acetaminophen/pharmacokinetics/*toxicity; Analgesics, Non-Narcotic/pharmacokinetics/*toxicity; Animals; Aryl Hydrocarbon Hydroxylases/biosynthesis; Biotransformation; Blotting, Northern; Chromatography, High Pressure Liquid; Cytochrome P-450 CYP3A; Membrane Proteins; Mice; Mice, Knockout; Oxidoreductases, N-Demethylating/biosynthesis; Pregnenolone Carbonitrile/pharmacology; Receptors, Cytoplasmic and Nuclear/*drug effects; Receptors, Steroid/*drug effects; Sulfhydryl Compounds/metabolism  
  Abstract The pregnane X receptor (PXR) is a ligand-activated transcription factor and member of the nuclear receptor superfamily. Activation of PXR represents an important mechanism for the induction of cytochrome P450 3A (CYP3A) enzymes that can convert acetaminophen (APAP) to its toxic intermediate metabolite, N-acetyl-p-benzoquinone imine (NAPQI). Therefore, it was hypothesized that activation of PXR plays a major role in APAP-induced hepatotoxicity. Pretreatment with the PXR activator, pregnenolone 16alpha-carbonitrile (PCN), markedly enhanced APAP-induced hepatic injury, as revealed by increased serum ALT levels and hepatic centrilobular necrosis, in wild-type but not in PXR-null mice. Further analysis showed that following PCN treatment, PXR-null mice had lower CYP3A11 expression, decreased NAPQI formation, and increased maintenance of hepatic glutathione content compared to wild-type mice. Thus, these results suggest that PXR plays a critical role in APAP-induced hepatic toxicity, probably by inducing CYP3A11 expression and hence increasing bioactivation.  
  Address Laboratory of Metabolism, CCR, NCI, NIH, Bethesda, Maryland 20892, USA  
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  ISSN (up) 1096-6080 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15456926 Approved no  
  Call Number refbase @ user @ Serial 71  
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Author Broekhuis, F.; Madsen, E.K.; Klaassen, B. url  doi
openurl 
  Title Predators and pastoralists: how anthropogenic pressures inside wildlife areas influence carnivore space use and movement behaviour Type Journal Article
  Year 2019 Publication Animal Conservation Abbreviated Journal Anim Conserv  
  Volume Issue Pages  
  Keywords cheetah; livestock; movement; human pressure; protected areas; space use  
  Abstract Abstract Across the globe, wildlife populations and their behaviours are negatively impacted by people. Protected areas are believed to be an antidote to increasing human pressures but even they are not immune to the impact of anthropogenic activities. Areas that have been set aside for the protection of wildlife therefore warrant more attention when investigating the impact of anthropogenic pressures on wildlife. We use cheetahs Acinonyx jubatus as a case study to explore how a large carnivore responds to anthropogenic pressures inside wildlife areas. Using GPS-collar data we investigate cheetah space use, both when moving and stationary, and movement parameters (speed and turn angles) in relation to human disturbance, distance to human settlement, livestock abundance and livestock site use inside wildlife areas. Space use was negatively influenced by human disturbance, resulting in habitat loss and fragmentation and potentially reducing landscape permeability between neighbouring wildlife areas. Cheetahs were also less likely to stop in areas where livestock numbers were high, but more likely to stop in areas that were frequently used by livestock. The latter could reflect that cheetahs are attracted to livestock however, cheetahs in the study area rarely predated on livestock. It is therefore more likely that areas that are frequently used by livestock attract wild herbivores, which in turn could influence cheetah space use. We did not find any effects of people and livestock on cheetahs? speed and turn angles which might be related to the resolution of the data. We found that cheetahs are sensitive to human pressures and we believe that they could be an indicator species for other large carnivores facing similar challenges. We suggest that further research is needed to determine the levels of anthropogenic pressures needed to maintain ecological integrity, especially inside wildlife areas.  
  Address  
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  Publisher John Wiley & Sons, Ltd (10.1111) Place of Publication Editor  
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  ISSN (up) 1367-9430 ISBN Medium  
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  Notes doi: 10.1111/acv.12483 Approved no  
  Call Number Equine Behaviour @ team @ Serial 6522  
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