Cutaneous Evaporation in Heat-Stressed Spotted Sandgrouse

The Condor ◽  
1986 ◽  
Vol 88 (1) ◽  
pp. 99 ◽  
Author(s):  
Jacob Marder ◽  
Idit Gavrieli-Levin ◽  
Pnina Raber
Keyword(s):  
Cutaneous Evaporation

Inhibiting ventilatory evaporation produces an adaptive increase in cutaneous evaporation in mourning doves Zenaida macroura

1999 ◽  
Vol 202 (21) ◽  
pp. 3021-3028 ◽  
Author(s):  
T.C. Hoffman ◽  
G.E. Walsberg
Keyword(s):  
Skin Surface ◽  
The Body ◽  
Evaporative Heat Loss ◽  
Evaporative Water ◽  
Zenaida Macroura ◽  
Ambient Temperatures ◽  
Rapid Adjustment ◽  
Mourning Doves ◽  
A Minor ◽  
Cutaneous Evaporation

We tested the hypothesis that birds can rapidly change the conductance of water vapor at the skin surface in response to a changing need for evaporative heat loss. Mourning doves (Zenaida macroura) were placed in a two-compartment chamber separating the head from the rest of the body. The rate of cutaneous evaporation was measured in response to dry ventilatory inflow at three ambient temperatures and in response to vapor-saturated ventilatory inflow at two ambient temperatures. At 35 degrees C, cutaneous evaporation increased by 72 % when evaporative water loss from the mouth was prevented, but no increase was observed at 45 degrees C. For both dry and vapor-saturated treatments, cutaneous evaporation increased significantly with increased ambient temperature. Changes in skin temperature made only a minor contribution to any observed increase in cutaneous evaporation. This indicates that Z. macroura can effect rapid adjustment of evaporative conductance at the skin in response to acute change in thermoregulatory demand.

Heat stress induces ultrastructural changes in cutaneous capillary wall of heat-acclimated rock pigeon

1999 ◽  
Vol 277 (4) ◽  
pp. R967-R974 ◽  
Author(s):  
Yehuda Arieli ◽  
Neomi Feinstein ◽  
Pnina Raber ◽  
Michal Horowitz ◽  
Jacob Marder
Keyword(s):  
Heat Stress ◽  
Heat Exposure ◽  
Ultrastructural Changes ◽  
Water Evaporation ◽  
Adrenergic Agonist ◽  
Hot Environment ◽  
Adrenergic Antagonist ◽  
Cooling Mechanism ◽  
Cutaneous Evaporation ◽  
Endothelial Gaps

In heat-acclimated rock pigeons, cutaneous water evaporation is the major cooling mechanism when exposed at rest to an extremely hot environment of 50–60°C. This evaporative pathway is also activated in room temperature by a β-adrenergic antagonist (propranolol) or an α-adrenergic agonist (clonidine) and inhibited by a β-adrenergic agonist (isoproterenol). In contrast, neither heat exposure nor drug administration activates cutaneous evaporation in cold-acclimated pigeons. To elucidate the mechanisms underlying this phenomenon, we studied the role of the ultrastructure and permeability of the cutaneous vasculature. During both heat stress and the administration of propranolol and clonidine, we observed increased capillary fenestration and endothelial gaps. Similarly, propranolol increased the extravasation of Evans blue-labeled albumin in the skin tissue. We concluded that heat acclimation reinforces a mechanism by which the activation of adrenergic signal transduction pathways alters microvessel permeability during heat stress. Consequently the flux of plasma proteins and water into the interstitial space is accelerated, providing an interstitial source of water for sustained cutaneous evaporative cooling.

Prevalence of cutaneous evaporation in Merriam's kangaroo rat and its adaptive variation at the subspecific level

2000 ◽  
Vol 203 (4) ◽  
pp. 773-781 ◽  
Author(s):  
R.L. Tracy ◽  
G.E. Walsberg
Keyword(s):  
Water Loss ◽  
Evaporative Water Loss ◽  
Evaporative Water ◽  
Kangaroo Rats ◽  
Dipodomys Merriami ◽  
Kangaroo Rat ◽  
Mesic Site ◽  
Merriam's Kangaroo Rat ◽  
Cutaneous Evaporation ◽  
Subspecific Level

Previous estimates suggested that ventilatory evaporation constitutes the major source of water loss in kangaroo rats (Dipodomys spp.). We quantified rates of water loss in Merriam's kangaroo rat (Dipodomys merriami) and demonstrate the degree to which acclimation to a particular thermal and hydric environment plays a role in the intraspecific variation in water loss evident in this species. We draw the following conclusions: (1) that water loss varies intraspecifically in Merriam's kangaroo rat, in association with habitats of contrasting aridity and temperature; (2) that animals from more xeric locations have lower water loss rates than those from more mesic sites; (3) that most water loss is cutaneous, with ventilatory evaporative water loss contributing, at most, only 44% to total evaporative water loss; and (4) that intraspecific differences in rates of water loss are not acclimatory, but fixed. After acclimating under the same conditions, xeric-site animals still show a 33% lower rate of evaporative water loss than mesic-site animals.

Sweating in cattle. IV. Control of sweat glands secretion

1959 ◽  
Vol 52 (1) ◽  
pp. 66-71 ◽  
Author(s):  
G. C. Taneja
Keyword(s):  
Nervous System ◽  
Body Temperature ◽  
Sympathetic Nervous System ◽  
Sweat Glands ◽  
Appreciable Effect ◽  
Air Temperatures ◽  
Before And After ◽  
Sympathetic Nervous ◽  
Cutaneous Evaporation ◽  
The University

Two calves (Aberdeen Angus and American Brahman) were used exposed to different combinations of wet- and dry-bulb temperatures in a psychromatric chamber at the Physiology Department of the University of Queensland. These animals were 7–8 months old when first exposed to heat.Effect of various drugs affecting the sympathetic nervous system (adrenaline, noradrenaline, Dibenamine, Priscol, atropine and acetylcholine) on the rate of cutaneous evaporation in calves was tested. Cutaneous evaporation was measured by means of a capsule before and after the administration of these drugs.Cutaneous evaporation increased with the introduction of adrenaline and was suppressed by the administration of Dibenamine. Noradrenaline and Priscol had no appreciable effect. Acetylcholine failed to stimulate sweating and atropine did not block the sweat glands.Sweat glands of cattle were, therefore, found to be functional and their innervation adrenergic. Cattle use sweat to prevent body temperature from rising, yet the amount of sweat secreted is not large enough to allow cattle to maintain thermoneutrality at high air temperatures.

A note on canary coloration of wool in Ghokla sheep as influenced by restricted frequency of access to water

1978 ◽  
Vol 90 (3) ◽  
pp. 641-642
Author(s):  
M. Singh ◽  
T. More
Keyword(s):  
Water Intake ◽  
Physiological Stress ◽  
Nutritional Deficiency ◽  
Adaptive Mechanism ◽  
Access To Water ◽  
Yellow Coloration ◽  
Cutaneous Evaporation ◽  
Body Heat ◽  
Indian Sheep

Yellowing of wool as a function of physiological stress caused by nutritional deficiency in the feed of sheep (Das, 1965) though not confirmed by subsequent studies (Singh et al. 1977) evoked interest in the role of physiological stress in causing canary staining of wool. Restricted water intake as is generally the case with sheep in arid or even semiarid regions during summer, imposes considerable physiological stress. Furthermore, canary coloration is thought to be a sequel to an adaptive mechanism to hot and humid conditions in Indian sheep which have a greater reliance on cutaneous evaporation for dissipating body heat (Acharaya & Singh, 1976). It was, therefore, decided to study the influence, if any, of restricting access to water on the canary coloration of wool (non-scourable yellow coloration of the autumn clip) in the stain-susceptible Chokla sheep

scholarly journals Avian thermoregulation in the heat: phylogenetic variation among avian orders in evaporative cooling capacity and heat tolerance

2017 ◽  
Author(s):  
Ben Smit ◽  
Maxine C. Whitfield ◽  
William A. Talbot ◽  
Alexander R. Gerson ◽  
Andrew E. McKechnie ◽  
...  
Keyword(s):  
Heat Tolerance ◽  
Heat Dissipation ◽  
Resting Metabolic Rate ◽  
Evaporative Cooling ◽  
Cooling Capacity ◽  
Evaporative Heat Loss ◽  
Cooling Efficiency ◽  
Evaporative Water ◽  
Cutaneous Evaporation ◽  
Hot Environments

AbstractLittle is known about the phylogenetic variation of avian evaporative cooling efficiency and heat tolerance in hot environments. We quantified thermoregulatory responses to high air temperature (Ta) in ~100-g representatives of three orders: African cuckoo (Cuculus gularis, Cuculiformes), lilac-breasted roller (Coracias caudatus, Coraciiformes), and Burchell’s starling (Lamprotornis australis, Passeriformes). All three species initiated respiratory mechanisms to increase evaporative heat dissipation when body temperature (Tb) approached 41.5°C in response to increasing Ta, with gular flutter observed in cuckoos and panting in rollers and starlings. Resting metabolic rate (RMR) and evaporative water loss (EWL) increased by quantitatively similar magnitudes in all three species, although maximum rates of EWL were proportionately lower in starlings. Evaporative cooling efficiency [defined as the ratio of evaporative heat loss (EHL) to metabolic heat production (MHP)] generally remained below 2.0 in cuckoos and starlings, but reached a maximum of ~3.5 in rollers. The high value for rollers reveals a very efficient evaporative cooling mechanism, and is similar to EHL/MHP maxima for similarly sized columbids which very effectively dissipate heat via cutaneous evaporation. This unexpected phylogenetic variation among the orders tested in the physiological mechanisms of heat dissipation is an important step toward determining the evolution of heat tolerance traits in desert birds.Summary statementWe show that avian evaporative cooling efficiency and heat tolerance display substantial taxonomic variation that are, unexpectedly, not systematically related to the use of panting versus gular flutter processes.

scholarly journals Design and testing of a sweat meter for the cutaneous evaporation determination in cattle

2020 ◽  
Vol 8 (3) ◽  
pp. 223-228
Author(s):  
Zoilo Andrés Correa García ◽  
Rómulo Campos Gaona ◽  
Hernando Flórez Díaz
Keyword(s):  
Cutaneous Evaporation ◽  
Design And Testing

Temperature regulation in the new-born lamb. VI. Heat exchanges in lambs in a hot environment

1962 ◽  
Vol 13 (1) ◽  
pp. 122 ◽  
Author(s):  
G Alexander ◽  
D Williams
Keyword(s):  
Water Loss ◽  
Good Evidence ◽  
Sweat Glands ◽  
Second Phase ◽  
Ambient Temperatures ◽  
Respiratory Loss ◽  
Air Temperatures ◽  
Cutaneous Evaporation ◽  
Heat Exchanges ◽  
Respiratory Evaporation

At ambient temperatures below about 30°C, respiratory and cutaneous evaporation were constant in normal lambs and lambs without sweat glands. Above 30°C, respiratory water loss increased steeply. Cutaneous water loss also increased, but at a slower rate than respiratory loss and only in the lambs with sweat glands. The efficiency of evaporation in cooling the lamb was close to 100%. The contribution of cutaneous blood flow to facilitation of heat loss in lambs lying down appeared to be low. At low environmental humidity, respiratory evaporation at all rates of normal shallow panting was approximately 4 mg per respiration; but in "second phase" breathing this was increased up to 12 mg per respiration, and total respiratory evaporation was not reduced. Lambs showed no evidence of distress when exposed for 6–12 hr to air temperatures of 40°C and water vapour pressures of' less than I5 mm Hg. Cutaneous loss tended to fall and respiratory loss to increase. Maximum rates of cutaneous and respiratory evaporation were estimated by suppressing evaporation from the skin or respiratory tract at 43°C. These values tended to be higher in crossbred lambs then in Merinos, and Merinos tended to reach maximum "sweating" rates under less severe heat stress than the crossbreds. Homeothermic equilibrium was approached when evaporation from neither site was suppressed, but rectal temperatures increased rapidly when cutaneous evaporation was prevented, and more rapidly still when respiratory evaporation was much reduced. The results also illustrate how a high metabolic rate decreases heat tolerance. These experiments provide good evidence that sheep do sweat, but that respiratory evaporation is quantitatively more important than sweating.

Temperature Regulation and Heat Balance in Flying White-necked Ravens, Corvus Cryptoleucus

1981 ◽  
Vol 90 (1) ◽  
pp. 267-281 ◽  
Author(s):  
DENNIS M. HUDSON ◽  
MARVIN H. BERNSTEIN
Keyword(s):  
Steady State ◽  
Body Temperature ◽  
Wind Tunnel ◽  
Body Surface ◽  
Heat Balance ◽  
Metabolic Heat ◽  
Steady State Levels ◽  
Cutaneous Evaporation ◽  
Body Heat ◽  
Respiratory Evaporation

During level flight at 10 m.s−1 in a wind tunnel, white-necked ravens (Corvus cryptoleucus, mass 0·48 kg) exhibited an increase in body temperature to steady-state levels as high as 45°C, exceeding resting levels by nearly 3°C. This reflects the storage of up to half of the metabolic heat produced (Hp) during 5 min of flight. During steady-state flight, body heat was dissipated in part by respiratory evaporation and convection (13–40% of Hp) evoked by increases in ventilation proportional to body temperature. Remaining heat was lost by cutaneous evaporation (10% of Hp) as well as by radiation and convection from the external body surface. The results suggest strategies that might be used by ravens during flight under desert conditions.

The rate of cutaneous evaporation in some tropical and temperate breeds of cattle in Nigeria

1975 ◽  
Vol 20 (1) ◽  
pp. 63-68 ◽  
Author(s):  
S. F. Amakiri ◽  
R. Mordi
Keyword(s):  
Evaporation Rate ◽  
Bos Taurus ◽  
Bos Indicus ◽  
Sweat Glands ◽  
Cattle Breeds ◽  
Lateral Thigh ◽  
White Fulani ◽  
Rate Of Evaporation ◽  
Cutaneous Evaporation

SUMMARYThe rate of cutaneous evaporation was highest in the White Fulani (Bos indicus) followed by the N'Dama and German Friesian (Bos taunts). The lowest rate of evaporation was recorded in the Muturu (Bos taurus brachyceros). In all breeds, the rate at 15.00 hr was significantly higher than at 18.00 hr.For the sites sampled, evaporation rate was highest on the hump and mid-side, followed by the neck and lateral thigh and lowest on the dewlap and navel flap.The possible correlation of these results with the size and distribution of the sweat glands on various sites of different cattle breeds is discussed.

Sign in / Sign up

Export Citation Format

Share Document