Physiological responses of a rodent to heliox reveal constancy of evaporative water loss under perturbing environmental conditions
Total evaporative water loss of endotherms is assumed to be determined essentially by biophysics, at least at temperatures below thermoneutrality, with evaporative water loss determined by the water vapor deficit between the animal and the ambient air. We present here evidence, based on the first me...
| Main Authors: | , |
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| Format: | Journal Article |
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American Physiological Society
2014
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| Online Access: | http://hdl.handle.net/20.500.11937/25159 |
| _version_ | 1848751630428667904 |
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| author | Cooper, Christine Withers, P. |
| author_facet | Cooper, Christine Withers, P. |
| author_sort | Cooper, Christine |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | Total evaporative water loss of endotherms is assumed to be determined essentially by biophysics, at least at temperatures below thermoneutrality, with evaporative water loss determined by the water vapor deficit between the animal and the ambient air. We present here evidence, based on the first measurements of evaporative water loss for a small mammal in heliox, that mammals may have a previously unappreciated ability to maintain acute constancy of total evaporative water loss under perturbing environmental conditions. Thermoregulatory responses of ash-grey mice (Pseudomys albocinereus) to heliox were as expected, with changes in metabolic rate, conductance, and respiratory ventilation consistent with maintaining constancy of body temperature under conditions of enhanced heat loss. However, evaporative water loss did not increase in heliox. This is despite our confirmation of the physical effect that heliox augments evaporation from nonliving surfaces, which should increase cutaneous water loss, and increases minute volume of live ash-grey mice in heliox to accommodate their elevated metabolic rate, which should increase respiratory water loss. Therefore, mice had not only a thermoregulatory but also a hygroregulatory response to heliox. We interpret these results as evidence that ash-grey mice can acutely control their evaporative water loss under perturbing environmental conditions and suggest that hygroregulation at and below thermoneutrality is an important aspect of the physiology of at least some small mammals. |
| first_indexed | 2025-11-14T07:55:47Z |
| format | Journal Article |
| id | curtin-20.500.11937-25159 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T07:55:47Z |
| publishDate | 2014 |
| publisher | American Physiological Society |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-251592017-09-13T15:21:50Z Physiological responses of a rodent to heliox reveal constancy of evaporative water loss under perturbing environmental conditions Cooper, Christine Withers, P. Total evaporative water loss of endotherms is assumed to be determined essentially by biophysics, at least at temperatures below thermoneutrality, with evaporative water loss determined by the water vapor deficit between the animal and the ambient air. We present here evidence, based on the first measurements of evaporative water loss for a small mammal in heliox, that mammals may have a previously unappreciated ability to maintain acute constancy of total evaporative water loss under perturbing environmental conditions. Thermoregulatory responses of ash-grey mice (Pseudomys albocinereus) to heliox were as expected, with changes in metabolic rate, conductance, and respiratory ventilation consistent with maintaining constancy of body temperature under conditions of enhanced heat loss. However, evaporative water loss did not increase in heliox. This is despite our confirmation of the physical effect that heliox augments evaporation from nonliving surfaces, which should increase cutaneous water loss, and increases minute volume of live ash-grey mice in heliox to accommodate their elevated metabolic rate, which should increase respiratory water loss. Therefore, mice had not only a thermoregulatory but also a hygroregulatory response to heliox. We interpret these results as evidence that ash-grey mice can acutely control their evaporative water loss under perturbing environmental conditions and suggest that hygroregulation at and below thermoneutrality is an important aspect of the physiology of at least some small mammals. 2014 Journal Article http://hdl.handle.net/20.500.11937/25159 10.1152/ajpregu.00051.2014 American Physiological Society unknown |
| spellingShingle | Cooper, Christine Withers, P. Physiological responses of a rodent to heliox reveal constancy of evaporative water loss under perturbing environmental conditions |
| title | Physiological responses of a rodent to heliox reveal constancy of evaporative water loss under perturbing environmental conditions |
| title_full | Physiological responses of a rodent to heliox reveal constancy of evaporative water loss under perturbing environmental conditions |
| title_fullStr | Physiological responses of a rodent to heliox reveal constancy of evaporative water loss under perturbing environmental conditions |
| title_full_unstemmed | Physiological responses of a rodent to heliox reveal constancy of evaporative water loss under perturbing environmental conditions |
| title_short | Physiological responses of a rodent to heliox reveal constancy of evaporative water loss under perturbing environmental conditions |
| title_sort | physiological responses of a rodent to heliox reveal constancy of evaporative water loss under perturbing environmental conditions |
| url | http://hdl.handle.net/20.500.11937/25159 |