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Author Hughes, K.L.; Sulaiman, I. openurl 
  Title The ecology of Rhodococcus equi and physicochemical influences on growth Type Journal Article
  Year 1987 Publication Veterinary Microbiology Abbreviated Journal Vet Microbiol  
  Volume 14 Issue 3 Pages 241-250  
  Keywords Animals; Feces/microbiology; Horses; Hydrogen-Ion Concentration; Rhodococcus/*growth & development; *Soil Microbiology; Temperature  
  Abstract Growth of Rhodococcus equi was studied in vitro. Optimal growth occurred under aerobic conditions between pH 7.0 and 8.5, at 30 degrees C. R. equi survived better in a neutral soil (pH 7.3) than it did in two acid soils (pH less than 5.5). It grew substantially better in soils enriched with faeces than in soils alone. Simple organic acids in horse dung, especially acetate and propionate, appear to be important in supporting growth of R. equi in the environment. The ecology of R. equi can be best explained by an environmental cycle allowing its proliferation in dung, influenced by management, grazing behaviour and prevailing climatic conditions. Preventive measures should be aimed at reducing or avoiding focal areas of faecal contamination in the environment.  
  Address School of Veterinary Science, University of Melbourne, Parkville, Vic., Australia  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (down) 0378-1135 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:3672866 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2678  
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Author Miksovska, J.; Larsen, R.W. openurl 
  Title Photothermal studies of pH induced unfolding of apomyoglobin Type Journal Article
  Year 2003 Publication Journal of Protein Chemistry Abbreviated Journal J Protein Chem  
  Volume 22 Issue 4 Pages 387-394  
  Keywords Acoustics; Animals; Apoproteins/*chemistry/metabolism; Circular Dichroism; Horses; Myocardium/chemistry; Myoglobin/*chemistry/metabolism; Photolysis; Protein Conformation/radiation effects; Protein Denaturation/radiation effects; *Protein Folding; Temperature; Thermodynamics  
  Abstract Conformational dynamic and enthalpy changes associated with pH induced unfolding of apomyoglobin were studied using photoacoustic calorimetry and photothermal beam deflection methods. The transition between the native state and the I intermediate was induced by a nanosecond pH jump from o-nitrobenzaldehyde photolysis. Deconvolution of photoacoustic waves indicates two kinetic processes. The fast phase (T < 50 ns) is characterized by a volume expansion of 8.8 ml mol(-1). This process is followed by a volume contraction of about -22 ml mol(-1) (tau approximately 500 ns). Photothermal beam deflection measurements do not reveal any volume changes on the time scale between approximately 100 micros and 5 ms. We associate the volume contraction with structural changes occurring during the transition between the native state and the I intermediate. The lack of any processes on the ms time scale may indicate the absence of structural events involving larger conformational changes of apomyoglobin after the pH jump.  
  Address Department of Chemistry, University of South Florida, Tampa, Florida 33620, USA  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (down) 0277-8033 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:13678303 Approved no  
  Call Number Equine Behaviour @ team @ Serial 3780  
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Author Thiel, D.; Jenni-Eiermann, S.; Palme, R. doi  openurl
  Title Measuring corticosterone metabolites in droppings of capercaillies (Tetrao urogallus) Type Journal Article
  Year 2005 Publication Annals of the New York Academy of Sciences Abbreviated Journal Ann N Y Acad Sci  
  Volume 1046 Issue Pages 96-108  
  Keywords Adrenocorticotropic Hormone/administration & dosage/analysis/metabolism; Animals; Circadian Rhythm; Corticosterone/administration & dosage/*analysis/*metabolism; Feces/*chemistry; Female; Freezing; Galliformes/*metabolism; Male; Reproducibility of Results; Sex Factors; Temperature; Time Factors; Tritium/diagnostic use  
  Abstract The capercaillie (Tetrao urogallus), the largest grouse species in the world, is decreasing in numbers in major parts of its distribution range. Disturbances by human outdoor activities are discussed as a possible reason for this population decline. An indicator for disturbances is the increase of the glucocorticoid corticosterone, a stress hormone, which helps to cope with life-threatening situations. However, repeated disturbances might result in a long-term increase of the basal corticosterone concentration, which can result in detrimental effects like reduced fitness and survival of an animal. To measure corticosterone metabolites (CMs) noninvasively in the droppings of free-living capercaillies, first an enzyme immunoassay (EIA) in captive birds had to be selected and validated. Therefore, the excretion pattern of intravenously injected radiolabeled corticosterone was determined and 3H metabolites were characterized. High-performance liquid chromatography (HPLC) separations of the samples containing peak concentrations revealed that corticosterone was extensively metabolized. The HPLC fractions were tested in several EIAs for glucocorticoid metabolites. The physiological relevance of this method was proved after pharmacological stimulation of the adrenocortical activity. Only the recently established cortisone assay, measuring CMs with a 3,11-dione structure, detected an expressed increase of concentrations following ACTH stimulation. To set up a sampling protocol suited for the field, we examined the influence of various storage conditions and time of day on concentrations of CMs.  
  Address Swiss Ornithological Institute, 6204 Sempach, Switzerland. dominik.thiel@vogelwarte.ch  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (down) 0077-8923 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16055846 Approved no  
  Call Number Equine Behaviour @ team @ Serial 4079  
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Author Chmel, L.; Hasilikova, A.; Hrasko, J.; Vlacilikova, A. openurl 
  Title The influence of some ecological factors on keratinophilic fungi in the soil Type Journal Article
  Year 1972 Publication Sabouraudia Abbreviated Journal Sabouraudia  
  Volume 10 Issue 1 Pages 26-34  
  Keywords Animals; Arthrodermataceae/growth & development/isolation & purification/metabolism; Carbohydrates; Czechoslovakia; Ecology; Fungi/growth & development/*isolation & purification/metabolism; Hair; Horses; Humic Substances; Humidity; Keratins/metabolism; Microsporum/isolation & purification; Mitosporic Fungi/isolation & purification; Phosphates; Seasons; Soil; *Soil Microbiology; Species Specificity; Temperature; Trichophyton/isolation & purification  
  Abstract  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN (down) 0036-2174 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:5063162 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2719  
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Author Yarnell, K.; Hall, C.; Billett, E. url  doi
openurl 
  Title An assessment of the aversive nature of an animal management procedure (clipping) using behavioral and physiological measures Type Journal Article
  Year 2013 Publication Physiology & Behavior Abbreviated Journal Physiol. Behav.  
  Volume 118 Issue Pages 32-39  
  Keywords Thermography; Eye temperature; Cortisol; Horse; Welfare; Clipping  
  Abstract Animal management often involves procedures that, while unlikely to cause physical pain, still cause aversive responses. The domestic horse (Equus caballus) regularly has excessive hair clipped off to facilitate its use as a riding/driving animal and this procedure causes adverse behavioral responses in some animals. The aim of this study was to compare behavioral and physiological measures to assess the aversive effect of this procedure. Ten horses were selected on the basis of being either compliant (C: n=5) or non-compliant (NC: n=5) during this procedure. The horses were subjected to a sham clipping procedure (SC: where the blades had been removed from the clippers) for a period of ten minutes. Measures were taken pre, during and post SC (-10min to +30min) and mean values calculated for ALL horses and for C and NC separately. Behavioral activity was scored (scale 1-5) by twenty students from video footage in (phase/group-blind scoring). Heart rate (HR), salivary cortisol and eye temperature were monitored throughout the procedure. The NC horses were found to be significantly more behaviorally active/less relaxed throughout the trial than C horses (p<0.05) with the greatest difference occurring during the SC procedure (p<0.01). NC horses were more active/less relaxed during, compared with pre or post SC (p<0.05), but showed no behavioral difference pre and post SC. HR of the NC horses was higher than that of the C horses throughout the trial but only significantly so after 10min of SC (p<0.01). ALL horses showed a significant increase in HR between +5 and +10min into the procedure (p<0.05). There was a significant increase in salivary cortisol concentration in ALL horses post procedure (p<0.01) with levels peaking at 20minute post SC. No significant differences in salivary cortisol concentration between C and NC were found at any stage of the trial. Eye temperature increased significantly in ALL horses during SC, peaking at +10min into the procedure (p<0.05) and then decreased substantially when SC had ceased (p<0.01). Although no significant differences were found between C and NC per se, there was a significant interaction between group and phase of trial (p<0.05) with the NC group showing a greater decrease in eye temperature post SC. There was a significant positive correlation between changes in salivary cortisol concentration and eye temperature (p<0.01) but no correlation between any of the other measures. Although the behavioral response of C and NC to this procedure was significantly different the physiological responses indicated that ALL horses found the procedure aversive. Eye temperature could be used as an objective and immediate measure of how an animal is responding to a specific situation in order to evaluate management procedures and adapt them where appropriate to reduce the negative impact on animal health and welfare.  
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  ISSN (down) 0031-9384 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 6611  
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Author Czerlinski, G.H.; Erickson, J.O.; Theorell, H. openurl 
  Title Chemical relaxation studies on the horse liver alcohol dehydrogenase system Type Journal Article
  Year 1979 Publication Physiological Chemistry and Physics Abbreviated Journal Physiol Chem Phys  
  Volume 11 Issue 6 Pages 537-569  
  Keywords Alcohol Oxidoreductases/*metabolism; Animals; Buffers; Electron Transport; Ethanol/metabolism; Horses; Hydrogen-Ion Concentration; Liver/*enzymology; Mathematics; NAD/metabolism; Oscillometry; Osmolar Concentration; Temperature; Time Factors  
  Abstract Chemical relaxation studies on the system horse liver alcohol dehydrogenase, nicotinamide adenine dinucleotide, and ethanol were conducted observing fluorescence changes between 400 and 500 nm. Temperature-jump experiments were performed at pH 6.5, 7.0, 8.0, and 9.0; concentration-jump experiments at pH 9.0. The reciprocal of the slowest relaxation time was found to be linearly dependent upon the enzyme concentration for relatively low enzyme concentrations, as predicted earlier. Use of the wide pH-range necessitated expression of the four apparent dissociation constants of the catalytic reaction cycle in terms of pH-independent constants. The system was described in terms of only one (or two) catalysis-linked protons not associated with the electron transfer. Protonic steps in a buffered system are in rapid equilibrium, too fast to be measured with the equipment available. Assuming only two of the four bimolecular reaction steps in the four-step cycle are fast compared to the remaining two, six cases may be considered with six expressions for the reciprocal of the slowest relaxation time. Comparison with the experimental data revealed that the bimolecular reaction steps governing the slowest relaxation time change with pH. Above the effective time resolution of the temperature-lump instrument with fluorescence detection (0.1 msec) only one other relaxation time was detectable and only at pH 9. This relaxation time, found to be independent of the concentration of all reactants within experimental error (r = 10 +/- 5 msec), is most likely due to an interconversion among ternary complexes.  
  Address  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN (down) 0031-9325 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:44918 Approved no  
  Call Number Equine Behaviour @ team @ Serial 3813  
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Author Ballew, R.M.; Sabelko, J.; Gruebele, M. openurl 
  Title Direct observation of fast protein folding: the initial collapse of apomyoglobin Type Journal Article
  Year 1996 Publication Proceedings of the National Academy of Sciences of the United States of America Abbreviated Journal Proc. Natl. Acad. Sci. U.S.A.  
  Volume 93 Issue 12 Pages 5759-5764  
  Keywords Animals; Apoproteins/*chemistry; Circular Dichroism; Horses; Kinetics; Muscle, Skeletal/chemistry; Myoglobin/*chemistry; *Protein Folding; Spectrometry, Fluorescence; Spectrophotometry, Infrared; Temperature  
  Abstract The rapid refolding dynamics of apomyoglobin are followed by a new temperature-jump fluorescence technique on a 15-ns to 0.5-ms time scale in vitro. The apparatus measures the protein-folding history in a single sweep in standard aqueous buffers. The earliest steps during folding to a compact state are observed and are complete in under 20 micros. Experiments on mutants and consideration of steady-state CD and fluorescence spectra indicate that the observed microsecond phase monitors assembly of an A x (H x G) helix subunit. Measurements at different viscosities indicate diffusive behavior even at low viscosities, in agreement with motions of a solvent-exposed protein during the initial collapse.  
  Address School of Chemical Sciences and Beckman Institute for Advanced Science and Technology, University of Illinois, Urbana, 61801, USA  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (down) 0027-8424 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:8650166 Approved no  
  Call Number Equine Behaviour @ team @ Serial 3798  
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Author Hagen, S.J.; Eaton, W.A. doi  openurl
  Title Two-state expansion and collapse of a polypeptide Type Journal Article
  Year 2000 Publication Journal of Molecular Biology Abbreviated Journal J Mol Biol  
  Volume 301 Issue 4 Pages 1019-1027  
  Keywords Animals; Computer Simulation; Cytochrome c Group/*chemistry/*metabolism; Horses; Kinetics; Lasers; Models, Chemical; Peptides/*chemistry/*metabolism; Protein Conformation; Protein Denaturation; *Protein Folding; Spectrometry, Fluorescence; Temperature; Thermodynamics  
  Abstract The initial phase of folding for many proteins is presumed to be the collapse of the polypeptide chain from expanded to compact, but still denatured, conformations. Theory and simulations suggest that this collapse may be a two-state transition, characterized by barrier-crossing kinetics, while the collapse of homopolymers is continuous and multi-phasic. We have used a laser temperature-jump with fluorescence spectroscopy to measure the complete time-course of the collapse of denatured cytochrome c with nanosecond time resolution. We find the process to be exponential in time and thermally activated, with an apparent activation energy approximately 9 k(B)T (after correction for solvent viscosity). These results indicate that polypeptide collapse is kinetically a two-state transition. Because of the observed free energy barrier, the time scale of polypeptide collapse is dramatically slower than is predicted by Langevin models for homopolymer collapse.  
  Address Laboratory of Chemical Physics, NIDDK, National Institutes of Health, Building 5, Bethesda, MD, 20892-0520, USA  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (down) 0022-2836 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:10966803 Approved no  
  Call Number Equine Behaviour @ team @ Serial 3790  
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Author Arnold, W.; Ruf, T.; Kuntz, R. doi  openurl
  Title Seasonal adjustment of energy budget in a large wild mammal, the Przewalski horse (Equus ferus przewalskii) II. Energy expenditure Type Journal Article
  Year 2006 Publication The Journal of experimental biology Abbreviated Journal J Exp Biol  
  Volume 209 Issue Pt 22 Pages 4566-4573  
  Keywords Animals; Animals, Wild/*physiology; Body Temperature; Body Temperature Regulation; Eating; *Energy Metabolism; Female; Heart Rate; Horses/*physiology; Male; Motor Activity; Pregnancy; Reproduction; *Seasons  
  Abstract Many large mammals show pronounced seasonal fluctuations of metabolic rate (MR). It has been argued, based on studies in ruminants, that this variation merely results from different levels of locomotor activity (LA), and heat increment of feeding (HI). However, a recent study in red deer (Cervus elaphus) identified a previously unknown mechanism in ungulates--nocturnal hypometabolism--that contributed significantly to reduced energy expenditure, mainly during late winter. The relative contribution of these different mechanisms to seasonal adjustments of MR is still unknown, however. Therefore, in the study presented here we quantified for the first time the independent contribution of thermoregulation, LA and HI to heart rate (f(H)) as a measure of MR in a free-roaming large ungulate, the Przewalski horse or Takhi (Equus ferus przewalskii Poljakow). f(H) varied periodically throughout the year with a twofold increase from a mean of 44 beats min(-1) during December and January to a spring peak of 89 beats min(-1) at the beginning of May. LA increased from 23% per day during December and January to a mean level of 53% per day during May, and declined again thereafter. Daily mean subcutaneous body temperature (T(s)) declined continuously during winter and reached a nadir at the beginning of April (annual range was 5.8 degrees C), well after the annual low of air temperature and LA. Lower T(s) during winter contributed considerably to the reduction in f(H). In addition to thermoregulation, f(H) was affected by reproduction, LA, HI and unexplained seasonal variation, presumably reflecting to some degree changes in organ mass. The observed phase relations of seasonal changes indicate that energy expenditure was not a consequence of energy uptake but is under endogenous control, preparing the organism well in advance of seasonal energetic demands.  
  Address Research Institute of Wildlife Ecology, University of Veterinary Medicine, Vienna, Savoyenstrasse 1, 1160 Vienna, Austria. walter.arnold@vu-wien.ac.at  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
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  ISSN (down) 0022-0949 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:17079726 Approved no  
  Call Number Serial 1782  
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Author Dyson, H.J.; Beattie, J.K. openurl 
  Title Spin state and unfolding equilibria of ferricytochrome c in acidic solutions Type Journal Article
  Year 1982 Publication The Journal of Biological Chemistry Abbreviated Journal J Biol Chem  
  Volume 257 Issue 5 Pages 2267-2273  
  Keywords Animals; *Cytochrome c Group; Electron Spin Resonance Spectroscopy; Heme; Horses; Hydrogen-Ion Concentration; Kinetics; Ligands; Myocardium; Protein Binding; Protein Conformation; Spectrophotometry; Temperature  
  Abstract Equilibrium, stopped flow, and temperature-jump spectrophotometry have been used to identify processes in the unfolding of ferricytochrome c in acidic aqueous solutions. A relaxation occurring in approximately 100 microseconds involves perturbation of a spin-equilibrium between two folded conformers of the protein with methionine-80 coordinated or dissociated from the heme iron. The protein unfolds more slowly, in milliseconds, with dissociation and protonation of histidine-18. These two transitions appear cooperative in equilibrium measurements at low (0.01 M) ionic strength, but are separated at higher (0.10 M) ionic strength. They are resolved under both conditions in the dynamic measurements. The spin-equilibrium description permits a unified explanation of a number of properties of ferricytochrome c in acidic aqueous solutions.  
  Address  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
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  ISSN (down) 0021-9258 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:6277891 Approved no  
  Call Number Equine Behaviour @ team @ Serial 3807  
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