Significance of sweating in heat tolerance of cattle

1958 ◽  
Vol 9 (4) ◽  
pp. 579 ◽  
Author(s):  
DF Dowling
Keyword(s):  
Body Temperature ◽  
Air Temperature ◽  
Heat Tolerance ◽  
Body Surface ◽  
Skin Surface ◽  
The Body ◽  
Low Humidity ◽  
Skin Moisture

Evidence is presented that sweating is of importance to cattle as a method of regulating body temperature in a hot, dry environment. Cattle were covered with polyethylene coats, which prevented the vaporization of skin moisture from the body surface. They were then exposed to high atmospheric temperatures. Significant differences (P < 0.001) between their rectal temperatures and those of the control animals were demonstrated. It is concluded that, in conditions of high air temperature and radiation and low humidity, differences in heat tolerance between one animal and another may be due to differences in the ability to dissipate heat in the vaporization of sweat on the skin surface.

Heat intolerance as a function of percent of body surface involved with miliaria rubra

1980 ◽  
Vol 239 (3) ◽  
pp. R233-R240 ◽  
Author(s):  
K. B. Pandolf ◽  
T. B. Griffin ◽  
E. H. Munro ◽  
R. F. Goldman
Keyword(s):  
Heat Stress ◽  
Body Temperature ◽  
Body Surface ◽  
Heat Storage ◽  
Sweat Rate ◽  
Skin Surface ◽  
Specific Region ◽  
The Body ◽  
Heat Acclimatization ◽  
Mean Body Temperature

Twenty-four heat-acclimatized male volunteers were wrapped as previously described (Am. J. Physiol. 239 (Regulatory Integrative Comp. Physiol. 8): R226-R232, 1980) but to produce miliaria rubra (heat rash) in specific regions of the body. Three experimental rash groups were involved: 1) the torso (17% total skin surface rashed, n = 6), 2) torso and arms (38%, n = 8), or 3) legs (41%, n = 6), while four subjects served as controls. All subjects were reexposed to walking in the heat on the 7th day after unwrapping, and again 14, 21, and 28 days after unwrapping. When compared to responses for the last heat acclimatization day, tolerance time and sweat rate were lower and mean body temperature and delta heat storage significantly higher for experimental rash subjects contrasted to the controls for up to 21 days; however, no significant differences between the three rashed groups were found. The critical amount of surface area for heat intolerance from heat rash appears to be related to the specific region of the body and associated sweating responses; smaller rashed areas of the trunk, because they have greater potential for abundant sweating, may produce similar responses to heat stress as larger rashed areas of the limbs. Heat intolerance due to rash was not resolved until after 21 days.

Body Temperature of the Camel and Its Relation to Water Economy

1956 ◽  
Vol 188 (1) ◽  
pp. 103-112 ◽  
Author(s):  
Knut Schmidt-Nielsen ◽  
Bodil Schmidt-Nielsen ◽  
S. A. Jarnum ◽  
T. R. Houpt
Keyword(s):  
Body Temperature ◽  
Water Conservation ◽  
Skin Surface ◽  
Diurnal Variations ◽  
The Body ◽  
Free Access ◽  
Heat Gain ◽  
Hot Environment ◽  
Access To Water ◽  
The Given

The rectal temperature of normal healthy camels at rest may vary from about 34°C to more than 40°C. Diurnal variations in the winter are usually in the order of 2°C. In summer the diurnal variations in the camel deprived of drinking water may exceed 6°C, but in animals with free access to water the variations are similar to those found in the winter. The variations in temperature are of great significance in water conservation in two ways. a) The increase in body temperature means that heat is stored in the body instead of being dissipated by evaporation of water. At night the excess heat can be given off without expenditure of water. b) The high body temperature means that heat gain from the hot environment is reduced because the temperature gradient is reduced. The effect of the increased body temperature on heat gain from the environment has been calculated from data on water expenditure. These calculations show that under the given conditions the variations in body temperature effect a considerable economy of water expenditure. The evaporative heat regulation in the camel seems to rest exclusively on evaporation from the skin surface (sweating), and there is no apparent increase in respiratory rate or panting connected with heat regulation. The evaporation from isolated skin areas increases linearly with increased heat load. The critical temperature at which the increase sets in is around 35°C. The fur of the camel is an efficient barrier against heat gain from the environment. Water expenditure is increased in camels that have been shorn.

Strain difference in thermoregulation of rats surviving extreme heat

1982 ◽  
Vol 52 (2) ◽  
pp. 410-415 ◽  
Author(s):  
F. Furuyama
Keyword(s):  
Body Temperature ◽  
Heat Tolerance ◽  
Strain Difference ◽  
Body Weight Loss ◽  
The Body ◽  
Sprague Dawley ◽  
Survival Times ◽  
Sprague Dawley Rats ◽  
Thermoregulatory System ◽  
Different Strains

The survival times of unanesthetized rats in 42.5 degree C. 48% rh were studied in 12 different strains. In males, Sprague-Dawley rats (P less than 0.01) and Fisher 344/MK (P less than 0.05) showed significantly higher heat tolerance than the other 9 strains. Among Sprague-Dawley rats, females tolerated heat longer than males (P less than 0.05). There was no difference in lethal body temperature according to strains and exposure temperatures (38.5–48.5 degree C). Maximum survivable body temperature was 43.1 degree C in males and 43.3 degree C in females. The body weight loss in heat was greater in Sprague-Dawley, Fisher 344/MK, and JCL:Wistar strains. The degree of saliva spreading during the equilibrium period just below the maximum survivable body temperature correlated significantly with heat tolerance and was found to be the index of strain difference in heat tolerance. These findings demonstrated that the thermoregulatory system of rats is controlled genetically, though survival times of individuals in different strains sometimes overlap.

scholarly journals The Regulation of Body Temperature in Extremes of Dry Heat

1912 ◽  
Vol 12 (4) ◽  
pp. 479-488 ◽  
Author(s):  
E. H. Hunt
Keyword(s):  
Body Temperature ◽  
Air Temperature ◽  
The Body ◽  
Strong Argument ◽  
Dry Heat ◽  
Healthy Man ◽  
Large Reserve

(1) Comfort and health can readily be maintained in dry heat where for long periods the air temperature is above that of the body.(2) The amount of water absolutely required, and actually consumed, is very large; and this is accounted for by the necessity for neutralising, in some circumstances, the whole heat of metabolism (requiring up to 6,000 c.c.) and in addition a variable but sometimes very large amount of heat added to the body by radiation and conduction.(3) A healthy man carries in his body a large reserve of water, this reserve being mainly stored in muscle and being so readily available that the percentage of water in the blood is not appreciably diminished even when several litres of water have been lost by sweating. If, however, it be extensively drawn on, replacement seems to occupy many hours, and this delay is an important factor, forming a strong argument against any undue or needless use of the stored water owing to restriction of drinking.

A New Method for Monitoring Deep Body Temperature from the Skin Surface

1973 ◽  
Vol 44 (1) ◽  
pp. 81-86 ◽  
Author(s):  
R. H. Fox ◽  
A. J. Solman ◽  
R. Isaacs ◽  
A. J. Fry ◽  
I. C. MacDonald
Keyword(s):  
Body Temperature ◽  
Heat Flow ◽  
Skin Surface ◽  
The Body ◽  
Deep Body Temperature ◽  
New Device ◽  
Body Shell ◽  
Electronic Thermometer ◽  
A New Technique ◽  
Deep Body

1. A new technique for monitoring the deep body temperature is described. The technique depends on creating a zone of zero heat-flow across the body shell; this brings the deep body temperature to the skin surface where it is measured with a simple electronic thermometer. 2. The new device gives a temperature closely comparable with other methods for measuring the deep body temperature in the resting subject, and is simple to use and socially acceptable.

scholarly journals Thermal Field Analysis of Two Kinds of Suspended Moxibustion

2021 ◽  
Author(s):  
Bo Zhang ◽  
Shan Huang ◽  
Hanrui Zhang ◽  
Haiyan Tu
Keyword(s):  
Body Temperature ◽  
Temperature Change ◽  
Thermal Field ◽  
Subcutaneous Tissue ◽  
Skin Surface ◽  
The Body ◽  
Field Analysis ◽  
Transfer Model ◽  
Suspended Moxibustion ◽  
Mild Moxibustion

Abstract Background: Moxibustion has been widely used in Chinese medicine treatment and health care, it is necessary to study the mechanism and characteristics of moxibustion treatment. The warm effect of moxibustion is closely related to the therapeutic effect. Studying the distribution and change of thermal field is an effective way to understand the mechanism of moxibustion. Methods: The finite element analysis software COMSOL was used to establish the heat transfer model to simulate the whole moxibustion process. Two kinds of suspended moxibustion methods, including mild moxibustion and sparrow-pecking moxibustion, were used to perform moxibustion trial at Zusanli acupoint (ST36) of volunteers, with Institutional Review Board (IRB) approval, and the thermal field on the skin surface was detected with an infrared thermometer. Results: Moxibustion method and moxibustion distance are the factors that affect the temperature change. The temperature rising speed of mild moxibustion was slower than that of sparrow-pecking moxibustion. When the moxibustion distance changes, the temperature changes obviously. If the moxibustion distance does not change, the body temperature will continue to rise slowly. If the distance increases, the body temperature will show a downward trend. On the contrary, it goes up. The thermal fields of mild moxibustion and sparrow-pecking moxibustion were distributed in concentric circles around Zusanli. After natural cooling, the temperature of subcutaneous tissue was higher than that of epidermis.Conclusion: The speed of skin temperature change is affected by the method of moxibustion. The temperature field characteristics formed on the skin surface and acupoint are affected by the moxibustion distance and the moxibustion duration. Moxibustion will produce warm heat stimulation to the subcutaneous tissue.

scholarly journals Hyperthermic Effect of Ginger (Zingiber officinale) Extract-Containing Beverage on Peripheral Skin Surface Temperature in Women

2018 ◽  
Vol 2018 ◽  
pp. 1-8
Author(s):  
Keiichiro Sugimoto ◽  
Hiroaki Takeuchi ◽  
Kazuya Nakagawa ◽  
Yasuhiro Matsuoka
Keyword(s):  
Body Temperature ◽  
Crossover Trial ◽  
Zingiber Officinale ◽  
Skin Surface ◽  
The Body ◽  
Cold Sensitivity ◽  
Skin Surface Temperature ◽  
Ginger Extract ◽  
Thermographic Camera ◽  
Cold Sensitive

Ginger is known to warm the body. Therefore, we conducted a placebo-controlled crossover trial to investigate the hyperthermic effect of a palatable ginger-containing beverage in healthy women with cold-sensitive extremities. Six women drank 280 mL of 0.07% ginger extract-containing or placebo beverage in a temperature-controlled room (21°C). Their palm temperatures were measured as measure of surface body temperature using a thermographic camera before intake and every 10 min after intake for 60 min. Palm temperature increased immediately following intake of the ginger and placebo beverages. However, palm temperature following intake of the ginger beverage increased for 20 min, while palm temperature following placebo intake decreased again after 10 min. The increased palm temperature following ginger intake was maintained significantly longer than after placebo intake (p < 0.05). In response to a questionnaire, some subjects answered that their increased body temperature was maintained after drinking the ginger beverage. Ginger extract-containing beverage may thus improve cold sensitivity.

Hibernation in the Eastern Pygmy Possum, Cercartetus-Nanus (Marsupialia, Burramyidae)

1993 ◽  
Vol 41 (1) ◽  
pp. 67 ◽  
Author(s):  
F Geiser
Keyword(s):  
Oxygen Consumption ◽  
Body Temperature ◽  
Metabolic Rate ◽  
Air Temperature ◽  
The Body ◽  
Daily Torpor ◽  
Rate Of Oxygen Consumption ◽  
The Mean ◽  
Cercartetus Nanus ◽  
Torpor Bouts

The pattern of torpor was examined in the eastern pygmy possum, Cercartetus nanus (21 g). Animals displayed torpor regularly in the laboratory, and the occurrence of torpor increased with decreasing air temperature (T(a)). At high T(a) (18-degrees-C) animals usually exhibited daily torpor, but torpor bouts of up to 2 days were observed occasionally. The duration of torpor bouts lengthened with a lowering of T(a) and the mean bout duration at T(a) = 5-degrees-C was 17.0 +/- 2.5 days. The minimum metabolic rate (measured as rate of oxygen consumption) of torpid individuals was 0.018 +/- 0.003 mL O2 g-1 h-1, which is less than 2% of the basal metabolic rate. The body temperature (T(b)) Of torpid animals fell to a minimum of 1.3 +/- 0.4-degrees-C. These results clearly demonstrate that Cercartetus nanus is a deep hibernator.

EFFET DU RAYONNEMENT LUMINEUX ET DE LA VITESSE DE L’AIR AMBIANT SUR LA TEMPÉRATURE CORPORELLE DES LARVES ET DES ADULTES DU DORYPHORE DE LA POMME DE TERRE

1997 ◽  
Vol 129 (5) ◽  
pp. 801-808
Author(s):  
Yvan Pelletier ◽  
Gilles Bélanger
Keyword(s):  
Wind Speed ◽  
Body Temperature ◽  
Light Intensity ◽  
Air Temperature ◽  
Leptinotarsa Decemlineata ◽  
The Body ◽  
Pomme De Terre ◽  
Potato Beetle ◽  
Rate Of Increase ◽  
Effect Of Light

AbstractThe effect of light intensity and wind speed on the body temperature of larvae and adults of the Colorado potato beetle (Leptinotarsa decemlineata (Say)) was studied in the laboratory. At a light intensity of 0.95 kW m−2 and without wind, the body temperature of larvae and adults was respectively 9.3 and 18.2 °C higher than air temperature. The temperature difference between the body temperature of larvae and adults and the air temperature increased linearly with an increase in light intensity. Wind speed had an important effect on the rate of increase of the body temperature as a function of light intensity in both larvae and adults. Our results demonstrated that the energy balance of larvae and adults differs.

scholarly journals Comparative physiological and hygienic assessment of the personal protective equipment EP-4(0) in the various assembly according to human thermal state indices

2021 ◽  
Vol 100 (3) ◽  
pp. 229-233
Author(s):  
Olga V. Burmistrova ◽  
Sergey Yu. Perov ◽  
Tatyana A. Konshina
Keyword(s):  
Heart Rate ◽  
Body Temperature ◽  
Air Temperature ◽  
Personal Protective Equipment ◽  
Thermal State ◽  
Heat Content ◽  
Operating Conditions ◽  
The Body ◽  
Protective Equipment ◽  
The Impact

Introduction. The article presents results of the study of the impact of the personal protective equipment EP-4 (0) in various assembly (overalls, jacket and trousers, jacket and semi-overall) from power frequency electric field and electrical shock on the thermal state of workers in a heating environment at air temperature 34.8 ○C and relative humidity 48%. Materials and methods. The study involved three men aged 35.3±4.6 years. They did the physical exercise for 40 minutes, had comfortable relaxation for 30 minutes after work. Recorded indices included skin temperature and moisture sensation score on 11 parts of the body, body temperature in the ear canal, heart rate, clothes temperature, heat sensation score, moisture loss, moisture evaporation efficiency. Results. Overalls using had the highest values of heat content, moisture score, heart rate changes, and body temperature increment. Heat content index in the body reached maximum permissible value using overalls earlier than other configurations. Conclusion. The research data showed overalls have the most significant impact on the human thermal state, jacket and trousers have the least impact, jacket and semi-overall take an intermediate place. The configuration including jacket and trousers, jacket and semi-overall under specific operating conditions is the most optimal. Such PPE assembly can be recommended for use in the open area in the summer season at an air temperature of 35 ○C and above, subject to protective requirements.

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