| |
Records |
Links |
|
Author |
Permyakov, S.E.; Khokhlova, T.I.; Nazipova, A.A.; Zhadan, A.P.; Morozova-Roche, L.A.; Permyakov, E.A. |
|
| |
Title |
Calcium-binding and temperature induced transitions in equine lysozyme: new insights from the pCa-temperature “phase diagrams” |
Type |
Journal Article |
| |
Year |
2006 |
Publication |
Proteins |
Abbreviated Journal |
Proteins |
|
| |
Volume |
65 |
Issue |
4 |
Pages |
984-998 |
|
| |
Keywords |
Animals; Apoproteins/chemistry/metabolism; Binding Sites; Calcium/chemistry/*metabolism; Cattle; Edetic Acid/metabolism; Horses/metabolism; Hydrogen-Ion Concentration; Lactalbumin/chemistry/metabolism; Muramidase/*chemistry/*metabolism; Protein Denaturation; Spectrometry, Fluorescence; *Temperature; Thermodynamics; Tryptophan/chemistry/metabolism |
|
| |
Abstract |
The most universal approach to the studies of metal binding properties of single-site metal binding proteins, i.e., construction of a “phase diagram” in coordinates of free metal ion concentration-temperature, has been applied to equine lysozyme (EQL). EQL has one relatively strong calcium binding site and shows two thermal transitions, but only one of them is Ca(2+)-dependent. It has been found that the Ca(2+)-dependent behavior of the low temperature thermal transition (I) of EQL can be adequately described based upon the simplest four-states scheme of metal- and temperature-induced structural changes in a protein. All thermodynamic parameters of this scheme were determined experimentally and used for construction of the EQL phase diagram in the pCa-temperature space. Comparison of the phase diagram with that for alpha-lactalbumin (alpha-LA), a close homologue of lysozyme, allows visualization of the differences in thermodynamic behavior of the two proteins. The thermal stability of apo-EQL (transition I) closely resembles that for apo-alpha-LA (mid-temperature 25 degrees C), while the thermal stabilities of their Ca(2+)-bound forms are almost indistinguishable. The native state of EQL has three orders of magnitude lower affinity for Ca(2+) in comparison with alpha-LA while its thermally unfolded state (after the I transition) has about one order lower (K = 15M(-1)) affinity for calcium. Circular dichroism studies of the apo-lysozyme state after the first thermal transition show that it shares common features with the molten globule state of alpha-LA. |
|
| |
Address |
Institute for Biological Instrumentation of the Russian Academy of Sciences, Pushchino, Moscow region 142290, Russia |
|
| |
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 |
1097-0134 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:17022083 |
Approved |
no |
|
| |
Call Number |
|
Serial |
1858 |
|
| Permanent link to this record |
| |
|
| |
|
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 |
|
| |
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 |
0022-0949 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:17079726 |
Approved |
no |
|
| |
Call Number |
|
Serial |
1782 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Pritchard, J.C.; Barr, A.R.S.; Whay, H.R. |
|
| |
Title |
Validity of a behavioural measure of heat stress and a skin tent test for dehydration in working horses and donkeys |
Type |
|
| |
Year |
2006 |
Publication |
Equine veterinary journal |
Abbreviated Journal |
Equine Vet J |
|
| |
Volume |
38 |
Issue |
5 |
Pages |
433-438 |
|
| |
Keywords |
Age Factors; Animal Welfare; Animals; Behavior, Animal/physiology; Body Temperature/*physiology; Body Weight/physiology; Case-Control Studies; Dehydration/diagnosis/pathology/*veterinary; Drinking; *Equidae; Female; Heat Stress Disorders/diagnosis/physiopathology/*veterinary; Horse Diseases/*diagnosis/pathology; Horses; Hypovolemia/diagnosis/physiopathology/veterinary; Male; Osmolar Concentration; Pakistan; Respiration; Skin/*pathology; Species Specificity; Work |
|
| |
Abstract |
REASONS FOR PERFORMING STUDY: Dehydration and heat stress are serious welfare issues for equids working in developing countries. There is a lack of any standardised method or validated interpretation of the skin tent test in horses and donkeys. Owners of dehydrated and heat-stressed animals often depend on veterinary examination for identification of these conditions, leading to delays in treatment and unnecessary reliance on external sources to effect welfare improvement. OBJECTIVES: To validate a standardised skin tent test for dehydration and a behavioural measure of heat stress in working equids; and to examine the effect of heat stress and dehydration on tripping and staggering behaviour. METHODS: The study was carried out on 130 working horses and donkeys in Pakistan. Associations between skin tent and blood parameters (packed cell volume [PCV], serum total protein [TP], serum osmolality), clinical parameters, resting and drinking behaviour were examined. Heat stress behaviour (increased respiratory rate and depth, head nodding, flared nostrils, apathy) was observed in conjunction with rectal temperature. Tripping and staggering were assessed using a simple obstacle course. RESULTS: In both species, heat stress behaviour was significantly associated with increased rectal temperature (P<0.001). A positive skin tent test was not significantly associated with PCV or TP, although in donkeys it was significantly associated with lower serum osmolality (P<0.001). More animals age >15 years had a positive skin tent than those in younger age groups (P = 0.037). Very thin horses were more likely to have a positive skin tent than those in thin or moderate condition (P = 0.028). There was no significant correlation between skin tent and tripping or staggering in either species. CONCLUSIONS AND POTENTIAL RELEVANCE: Heat stress behaviour is related to increased body temperature in working horses and donkeys. Owners may use this to make judgements regarding rest and cooling, precluding the need to seek veterinary attention. The skin tent test for dehydration used in this study did not show a significant relationship with PCV or TP. However, the use of blood parameters to validate the skin tent test may be confounded by anaemia, hypoproteinaemia or electrolyte depletion. Alternative methods are needed to confirm or refute the validity of the skin tent test in working equids. |
|
| |
Address |
Department of Clinical Veterinary Science, University of Bristol, Langford, UK |
|
| |
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 |
0425-1644 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:16986604 |
Approved |
no |
|
| |
Call Number |
|
Serial |
1784 |
|
| Permanent link to this record |
| |
|
| |
|
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. |
|
| |
Address |
|
|
| |
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 |
0021-8812 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:3988655 |
Approved |
no |
|
| |
Call Number |
refbase @ user @ |
Serial |
54 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Shaw, E.B.; Houpt, K.A.; Holmes, D.F. |
|
| |
Title |
Body temperature and behaviour of mares during the last two weeks of pregnancy |
Type |
Journal Article |
| |
Year |
1988 |
Publication |
Equine veterinary journal |
Abbreviated Journal |
Equine Vet J |
|
| |
Volume |
20 |
Issue |
3 |
Pages |
199-202 |
|
| |
Keywords |
Animals; *Behavior, Animal; *Body Temperature; Circadian Rhythm; Eating; Female; Horses/*physiology; Labor, Obstetric/*physiology; Motor Activity; Pregnancy; Pregnancy, Animal/*physiology |
|
| |
Abstract |
Average daily core body temperature and behavioural patterns of pregnant mares were studied, in search of definitive signs of parturition within 24 h of the event. Nineteen pony mares were sampled twice daily for core body temperature. A significant temperature drop, averaging 0.1 degrees C (0.2 degrees F) was observed during the day prior to parturition. Between 18.00 h and 06.00 h, during the two weeks before parturition, Thoroughbred and Standardbred mares (n = 52) spent an average 66.8 per cent of their time standing, 27.0 per cent eating, 4.9 per cent lying in sternal recumbency, 1.0 per cent lying in lateral recumbency, and 0.3 per cent walking. On the night before parturition, mares spent significantly less time lying in sternal recumbency than on previous nights and on the night of parturition all behaviour patterns except eating were significantly different from the nights of the two weeks before parturition. There was an increase in walking (5.3 per cent), lying in sternal recumbency (8 per cent) and lying in lateral recumbency (5.3 per cent) whereas standing (53.3 per cent) was decreased. In 58 observed pregnancies, 54 mares (97 per cent) foaled in a recumbent position and 50 mares (86 per cent) foaled between 18.00 h and 06.00 h. |
|
| |
Address |
Department of Physiology, New York State College of Veterinary Medicine, Cornell University, Ithaca 14853 |
|
| |
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 |
0425-1644 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:3402416 |
Approved |
no |
|
| |
Call Number |
refbase @ user @ |
Serial |
46 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Rodier, F. |
|
| |
Title |
[Spectral properties of porcine plasminogen: study of the acidic transition (author's transl)] |
Type |
Journal Article |
| |
Year |
1976 |
Publication |
European journal of biochemistry / FEBS |
Abbreviated Journal |
Eur J Biochem |
|
| |
Volume |
63 |
Issue |
2 |
Pages |
553-562 |
|
| |
Keywords |
Animals; Binding Sites; Guanidines; Hydrogen-Ion Concentration; *Plasminogen; Protein Binding; Protein Conformation; Spectrometry, Fluorescence; Spectrophotometry; Spectrophotometry, Ultraviolet; Swine; Temperature |
|
| |
Abstract |
The acidic transition of porcine plasminogen, prepared by affinity chromatography, was studied by non-destructive methods. These methods are based on the analysis of the behaviour of the tryptophyls under various conditions. The perturbation of the absorption and emission spectra by pH or temperature and the dynamic quenching of the intrinsic fluorescence are used to obtain information on structural changes which affect the environment of these residues. It is shown that by decreasing pH the fluorescence emission spectra are shifted toward the long wavelengths, with a broadening of the fluorescence band. The same effect can be obtained at constant pH by heating the protein solution. In order to analyze these phenomena, it is assumed that the fluorescence intensities at 355 nm and 328 nm reflect the proportion of the tryptophans which are exposed to the solvent, and buried, respectively. The plot of the ratio of the fluorescence intensities at these wavelengths versus pH or temperature leads to a titration curve showing an unmasking of tryptophans. The proportion of exposed tryptophans is measured by the dynamic fluorescence quenching technique and the data analyzed according to Lehrer. The plot of the fraction of exposed tryptophyls versus pH also shows the unmasking of these chromophores. Thermal perturbation of a solution of plaminogen at neutral pH induces a difference absorption spectrum whose amplitudes at the maxima are proportional to the number of exposed aromatic residues. The comparison with a solution of fully denatured plasminogen in 6 M guanidium chloride, where all the tryptophyls are exposed, shows that the percentage of exposure is equal to 59%. This number is significantly higher than the percentage found by the fluorescence quenching technique (20%), indicating that some tryptophyls are located in crevices, exposed to the solvent but not to the iodide. At acidic pH the absorption difference spectra induced by thermal perturbation are not classical, since they show an inversion and a new band between 300 nm and 305 nm. This band is mentioned in the literature as a minor band of tryptophan which appears when this chromophore is located in an asymmetric environment. On plotting the maximum amplitude of these spectra obtained at acidic pH versus temperature, we obtain a curve indicating that two types of antagonistic interactions are involved in the perturbation of the chromophores spectra. The spectrophotometric titration of plasminogen gives classical absorption difference spectra. By plotting the maximum amplitude at 292 nm versus pH, we obtain a titration curve with an apparent pK of 2.9 units. This pK is acidic which respect to the pK value of a normal carboxyl. This low value can be due to a positively charged group in the neighbourhood of a carboxyl, which interacts with one or more chromophores. When the carboxyl becomes protonated, this positively charged group is free and available to perturb the environment of some chromophores... |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
French |
Summary Language |
|
Original Title |
Proprietes spectrales du plasminogene porcin. Etude de la transition acide |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0014-2956 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:4326 |
Approved |
no |
|
| |
Call Number |
Admin @ knut @ |
Serial |
22 |
|
| Permanent link to this record |
