Low temperatures in northern winters are energetically challenging for mammals, and a special energetic burden is expected for diminutive species like shrews, which are among the smallest of mammals. Surprisingly, shrews shrink their body size in winter and reduce body and brain mass, an effect known as Dehnel's phenomenon, which is suggested to lower absolute energy intake requirements and the...

Artiodactyls employ selective brain cooling (SBC) regularly during experimental hyperthermia. In free-ranging antelopes, however, SBC often was present when body temperature was low but absent when brain temperature was near 42°C. The primary effect of SBC is to adjust the activity of the heat loss mechanisms to the magnitude of the heat stress rather than to the protection of the brain from th...

Factors were analyzed that limit the range of environmental conditions in which stress from heat may be relieved by evaporative cooling in shaded animals. Evaporative cooling reduces air temperature (Ta), but increases humidity. Equations were developed to predict Ta reduction as a function of ambient temperature and humidity and of humidity in cooled air. Predictions indicated that a reduction...

Daily locomotor activity, core body temperature, and their circadian rhythms were measured in lines of mice selected for high (MH) or low (ML) heat loss and unselected controls (MC). Lines were created by selecting for 16 generations in each of three replicates. Collection of locomotor activity and core temperature data spanned Generations 20 and 21 for a total of 352 mice. Physical activity an...

an investigation was carried out to study the effect of sole heat treatment and sole 1- methyl cyclo propine (1- mcp) as well as in combination on storage quality of strawberries. the factorial experiment was conducted using a completely randomized design of three replications. treatments included heat treatment at two levels (room teperature, 45°c for 3h) and 1- mcp at two levels (0, 1µl l-1)....

This study demonstrates the changes in six different pathophysiological parameters such as body weight, body temperature, fecal pellet count, blood-brain barrier (BBB) permeability, plasma corticosterone level and emergence of hemorrhagic peptic ulcer spots due to exposure to high environmental heat in three different age groups of freely moving rats. Methods: Each age group of rats was sub di...

Variable thermal environments experienced by most organisms warrant mechanisms to adjust the expression of phenotypic values to environmental needs. Here we explored short(mainly developmental plasticity) and long-term effects (genetic differentiation across altitudes) of temperature variation using copper butterflies as model organisms. Lower compared to higher developmental temperatures yield...

Endothermic animals, such as birds and mammals, regulate their body temperature balancing the amount of heat metabolically produced and that exchanged with the environment. Thus, whenever ambient temperature rises and/or metabolic heat production increases (such as during exercise), adjustments to promote heat dissipation are activated to defend body temperature. One of such adjustments modulat...