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Author  |
Arnold, W.; Ruf, T.; Kuntz, R. | ||||
| 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 | ||||
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| Language | English | Summary Language | Original Title | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0022-0949 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:17079726 | Approved | no | ||
| Call Number | Serial | 1782 | |||
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| Author |
Balakrishnan, G.; Hu, Y.; Spiro, T.G. | ||||
| Title | Temperature-jump apparatus with Raman detection based on a solid-state tunable (1.80-2.05 microm) kHz optical parametric oscillator laser | Type | Journal Article | ||
| Year | 2006 | Publication | Applied Spectroscopy | Abbreviated Journal | Appl Spectrosc |
| Volume | 60 | Issue | 4 | Pages | 347-351 |
| Keywords | Animals; Cytochromes c/analysis; Horses; Lasers; Myoglobin/metabolism; Spectrum Analysis, Raman/*instrumentation/*methods; *Temperature | ||||
| Abstract | The operating characteristics of a pulsed (10 ns) tunable near-infrared (NIR) laser source are described for temperature-jump (T-jump) applications. A Q-switched Nd:YLF laser (approximately 10 ns pulses) with a 1 kHz repetition rate is used to pump a potassium titanyl arsenate (KTA) crystal-based optical parametric oscillator (OPO), producing approximately 1 mJ NIR pulses that are tunable (1.80-2.05 microm) across the 1.9 microm vibrational overtone band of water. This T-jump source has been coupled to a deep ultraviolet (UV) probe laser for Raman studies of protein dynamics. T-jumps of up to 30 degrees C, as measured via the O-H stretching Raman band of water, are readily achieved. Application to cytochrome c unfolding is demonstrated. | ||||
| Address | Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA | ||||
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| Language | English | Summary Language | Original Title | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0003-7028 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:16613628 | Approved | no | ||
| Call Number | Equine Behaviour @ team @ | Serial | 3764 | ||
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| Author |
Ballew, R.M.; Sabelko, J.; Gruebele, M. | ||||
| 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 | ||||
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| Language | English | Summary Language | Original Title | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0027-8424 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:8650166 | Approved | no | ||
| Call Number | Equine Behaviour @ team @ | Serial | 3798 | ||
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| Author |
Bayley, P.; Martin, S.; Anson, M. | ||||
| Title | Temperature-jump circular dichroism: observation of chiroptical relaxation processes at millisecond time resolution | Type | Journal Article | ||
| Year | 1975 | Publication | Biochemical and Biophysical Research Communications | Abbreviated Journal | Biochem Biophys Res Commun |
| Volume | 66 | Issue | 1 | Pages | 303-308 |
| Keywords | *Alcohol Oxidoreductases/metabolism; Animals; Circular Dichroism; Horses; Kinetics; Liver/enzymology; Mathematics; Protein Conformation; Temperature; Time Factors | ||||
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| Language | English | Summary Language | Original Title | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0006-291X | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:1172440 | Approved | no | ||
| Call Number | Equine Behaviour @ team @ | Serial | 3816 | ||
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| Author |
Brinkmann, L.; Gerken, M.; Riek, A. | ||||
| Title | Energetic adaptations of Shetland pony mares | Type | Conference Article | ||
| Year | 2015 | Publication | Proceedings of the 3. International Equine Science Meeting | Abbreviated Journal | Proc. 3. Int. Equine. Sci. Mtg |
| Volume | Issue | Pages | |||
| Keywords | Body temperature, Energy expenditure, Food restriction, Hypometabolism, Locomotor activity, Shetland pony | ||||
| Abstract | Recent results suggest that wild Northern herbivores exhibit signs of a hypometabolism during times of low ambient temperature and food shortage in order to reduce their energetic needs. However, there are speculations that domestic animals lost the ability to reduce energy expenditure. To examine energetic and behavioural responses 10 Shetland pony mares were exposed to different environmental conditions (summer and winter). During winter ponies were allocated into two groups receiving two different food quantities (60% and 100% of maintenance energy requirement). We measured the field metabolic rate, water turn over, body temperature, locomotor activity, lying time, resting heart rate, body mass and body condition score. In summer, the field metabolic rate of all ponies (FMR; 63.4±15.0 MJ/day) was considerably higher compared with food restricted and control animals in winter (24.6±7.8 and 15.0±1.1 MJ/day, respectively). Furthermore, during summer, locomotor activity, resting heart rate and total water turnover were significantly elevated (P<0.001) compared with winter. Animals receiving a reduced amount of food (N=5) reduced their FMR by 26% compared with control animals (N=5) to compensate for the decreased energy supply. Furthermore, resting heart rate, body mass and body condition score were lower(29.2±2.7 beats/min, 140±22 kg and 3.0±1.0 points, respectively) than in control animals (36.8±41 beats/min, 165±31 kg, 4.4±0.7 points; P<0.05). While no difference could be found in the observed behaviour, nocturnal hypothermia was elevated in restrictively fed animals. Our results indicate that ponies adapt to different climatic conditions by changing their metabolic rate, behaviour and some physiological parameters. When exposed to energy shortage, ponies, like wild herbivores, exhibited hypometabolism and nocturnal hypothermia. Keywords: Body temperature, Energy expenditure, Food restriction, Hypometabolism, Locomotor activity, Shetland pony |
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| Corporate Author | Brinkmann, L. | Thesis | |||
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| Notes | Approved | no | |||
| Call Number | Equine Behaviour @ team @ | Serial | 5893 | ||
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| Author |
Chmel, L.; Hasilikova, A.; Hrasko, J.; Vlacilikova, A. | ||||
| 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 | ||||
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| Language | English | Summary Language | Original Title | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0036-2174 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:5063162 | Approved | no | ||
| Call Number | Equine Behaviour @ team @ | Serial | 2719 | ||
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| Author |
Cho, K.C.; Chan, K.K. | ||||
| Title | Kinetics of cold-induced denaturation of metmyoglobin | Type | Journal Article | ||
| Year | 1984 | Publication | Biochimica et Biophysica Acta (BBA) – Protein Structure and Molecular Enzymology | Abbreviated Journal | |
| Volume | 786 | Issue | 1-2 | Pages | 103-108 |
| Keywords | Metmyoglobin denaturation; Temperature jump; Denaturation kinetics; Conformational transformation; (Horse heart) | ||||
| Abstract | Using a slow temperature-jump spectrophotometer, we have studied the kinetics of cold-induced denaturation of metmyoglobin between 0[degree sign]C and 20[degree sign]C at acidic pH. The time-scale of the transition is slow and is of the order of minutes. The results are consistent with the transition's involving a total of three states, native (N), transient intermediate (I) and denatured (D), which are converted from one to the other in that order. | ||||
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| Notes | Approved | no | |||
| Call Number | refbase @ user @ | Serial | 3978 | ||
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| Author |
Crowell-Davis, S.L.; Houpt, K.A.; Carnevale, J. | ||||
| Title | Feeding and drinking behavior of mares and foals with free access to pasture and water | Type | Journal Article | ||
| Year | 1985 | Publication | Journal of animal science | Abbreviated Journal | J. Anim Sci. |
| Volume | 60 | Issue | 4 | Pages | 883-889 |
| Keywords | Animals; *Drinking Behavior; *Feeding Behavior; Female; Horses/*physiology; Male; Poaceae; Seasons; Temperature; Time Factors | ||||
| Abstract | The feeding and drinking behavior of 11 mares and 15 foals living on pasture with free access to water was recorded during 2,340 15-min focal samples taken over 2 yr. Lactating mares on pasture spent about 70% of the day feeding. Foals began feeding on their first day of life. As they grew older, they spent progressively more time feeding, but still spent only 47 +/- 6% of the time feeding by 21 wk of age. Foals fed primarily during the early morning and evening. While grass formed the major proportion of the diet of both foals and mares, they also ate clay, humus, feces, bark, leaves and twigs. Almost all feeding by foals was done while their mothers were feeding. Movement to water sources was frequently, but not invariably, carried out by an entire herd. Frequency (P = .005) but not duration (P greater than .05) of drinking bouts by mares increased as the temperature increased. Frequency was greatest at 30 to 35 C, at which temperature mares drank once every 1.8 h. Frequency of drinking varied with the time of day (P less than .01), being rarest during the early morning (0500 to 0900 h eastern daylight time) and most frequent during the afternoon (1300 to 1700 h). Drinking by foals was very rare. The youngest age at which a foal was observed to drink was 3 wk, and 8 of 15 foals were never observed to drink before weaning. | ||||
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| Language | English | Summary Language | Original Title | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0021-8812 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:3988655 | Approved | no | ||
| Call Number | refbase @ user @ | Serial | 54 | ||
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| Author |
Czerlinski, G.H.; Erickson, J.O.; Theorell, H. | ||||
| 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. | ||||
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| Language | English | Summary Language | Original Title | ||
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| ISSN | 0031-9325 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:44918 | Approved | no | ||
| Call Number | Equine Behaviour @ team @ | Serial | 3813 | ||
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| Author |
Duncan, I.J.H.; Widowski, T.M.; Malleau, A.E.; Lindberg, A.C.; Petherick, J.C. | ||||
| Title | External factors and causation of dustbathing in domestic hens | Type | Journal Article | ||
| Year | 1998 | Publication | Behavioural Processes | Abbreviated Journal | Behav. Process. |
| Volume | 43 | Issue | 2 | Pages | 219-228 |
| Keywords | Dustbathing; Illumination; Laying hens; Radiant heat; Social facilitation; Temperature | ||||
| Abstract | Dustbathing is known to be motivated by complex interactions between internal factors which build up over time and external factors, such as the sight of a dusty substrate. In this study, the effects of other external factors were investigated. Environmental temperature was shown to be important; frequencies of dustbathing were greater when hens were held at 22 than at 10[degree sign]C (P<0.01). In a second experiment, a radiant heat source or a radiant heat+light source, balanced to give the same radiant heat, resulted in more dustbathing behaviour during a 1-h stimulus period than during the same period with no stimulus (P<0.05). Components of dustbathing were increased more by the heat+light stimulus than by the heat stimulus alone (P<0.03). In a third experiment, the amount of dustbathing performed by individual hens in cages with dustbaths was increased by the presence of a group of hens dustbathing in an adjoining pen with a dustbath compared with the amount occurring when the hens were absent from the pen. | ||||
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| Notes | Approved | no | |||
| Call Number | Equine Behaviour @ team @ | Serial | 3607 | ||
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