Rates of heat and water loss in female mink (Mustela vison) measured by direct calorimetry
| Autor: | Søren Wamberg |
|---|---|
| Rok vydání: | 1994 |
| Předmět: |
medicine.medical_specialty
Environment controlled Calorimetry Oxygen Consumption Animal science biology.animal medicine Animals Mink Transepidermal water loss biology Chemistry Temperature Heat losses Direct calorimetry General Medicine Water Loss Insensible Surgery Kinetics Energy expenditure Metabolic rate Thermodynamics Female Energy Metabolism Body Temperature Regulation |
| Zdroj: | Comparative Biochemistry and Physiology Part A: Physiology. 107:451-458 |
| ISSN: | 0300-9629 |
| DOI: | 10.1016/0300-9629(94)90024-8 |
| Popis: | The energy expenditure (EE) of adult female mink was studied by continuous 24-hr measurement of rates of total heat loss (THL) in a controlled environment using a 24 m 3 calorimeter allowing separate on-line determination of sensitive (SHL) and evaporative (EHL) heat loss within the range of 20–200 W (72–720 kJ/hr). In four adult female mink (scanblack colour mutant), studied in transparent cages and given free access to feline food pellets and water, the mean 24-hr energy expenditure (=THL) under controlled experimental conditions was 8.9 W/kg (range: 5.5–13.1 W/kg) at 18°C and 5.8 W/kg (range: 4.3–9.5 W/kg) at 24°C. The results are in agreement with the data reported in the literature on the metabolic rate of adult farm-raised mink, calculated from rates of oxygen uptake under controlled experimental conditions, and with the energy requirement for maintenance, 586 kJ/kg/day (6.8 W/kg) recommended by the NRC. Under the experimental conditions of the present study the mean rate of total evaporative water loss (TEWL) amounted to 3.7 g/kg/hr at 18°C and 5.5 g/kg/hr at 24°C. The contributions of SHL and EHL to 24-hr THL in female mink were inversely related and markedly dependent on chamber temperature. When corrected for evaporated urinary and faecal water, SHL and EHL amounted to 76 and 24% of THL at 18°C, but at 24°C the corresponding values were 41 and 59%. The mean rate of insensible water loss, calculated as total evaporative water loss minus faecal and urinary water evaporated from the bedding material, amounted to about 84–90% of TEWL or 3.1 g/kg/hr at 18°C and 5.0 g/kg/hr at 24°C. The increase of EE in response to ambient temperatures below the thermoneutral zone (“metabolic coefficient”) calculated from the difference between the minimum values for the EE at 18 and 24°C amounted to 0.20W/°C/kg. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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