Jacob E. Wiebers

A Review of Temperature Regulation in Bats (Chiroptera)

The thermal regulatory responses of bats to ambient temperature have been reviewed. The various types of bats (hibernators, migrators, tropical) have some degree of thermal regulation, although the complexity of its nature and mechanism is still unknown.

Anaerobic glycolysis in cardiac tissue from a hibernator and non-hibernator as effected by temperature and hypoxia

Abstract 1. 1. Rates of anaerobic glycolysis were measured in cardiac tissue from hypoxic ground squirrels (Citellus tridecemlineatus) and albino rats. 2. 2. After hypoxia glycolysis increased significantly in both species at 38°C. At temperatures from 5 to 38°C glycolytic rates were significantly higher in tissue from control active (summer) or hibernating (winter) ground squirrels as compared to control rats. Glycolysis increased significantly during hibernation. 3. 3. At low temperatures energies of activation (EA) for glycolysis in rat tissue were higher than those in ground squirrel tissue. 4. 4. Interspecific differences in glycolytic rates support the hypothesis that the hibernator is better adapted to hypoxia and hypothermia than the homeotherm.

Seasonal Changes in Food Consumption of Little Brown Bats Held in Captivity at a “Neutral” Temperature of 92° F

Little brown bats, Myotis lucifugus , were maintained on a diet of mealworms in captivity throughout most of one year at a neutral temperature of 92° F. An attempt was made to maintain constant body weights of bats within the normal range of those in nature. Under these conditions, seasonal and sex variations in food consumption were observed. Major differences in food consumption were thought to result from a shift in the zone of thermal neutrality and alterations in the female reproductive cycle. Food consumption and body weight in M. lucifugus appear to follow a seasonal cycle under constant laboratory conditions.

The Effect of Temperature on Glycolysis in Brain and Skeletal Muscle from a Hibernator and a Non-Hibernator

M AMMALIAN hibernation represents a unique adaptation to extended periods of thermal stress. Natural hibernators attain a state of deep torpor during the winter, and their physiological integrity is maintained at body temperatures (5 + 3 C) that adult homeotherms cannot survive. Thus it seems reasonable to postulate that hibernators possess cellular adaptations to cold that are not found in the non-hibernator. This hypothesis is supported by South (1958), who investigated oxygen consumption in heart ventricle tissue from hamsters and albino

Urine concentration dynamics in the postprandial and the fasting Myotis lucifugus lucifugus

Abstract 1. 1. The postprandial bat initially increased urine flow rate and urine concentration and 7–9.5 hr later decreased urine flow rate while maintaining an elevated urine concentration. 2. 2. The fasting bat produced an increasingly concentrated urine at a uniform rate. 3. 3. The relationship of osmotic clearance to urine flow rate in the postprandial bat suggests an increase in glomerular filtration rate (GFR) in the bat kidney in response to food intake and a decrease in GFR when wastes have been removed. 4. 4. Alterations in GFR with feeding may aid this periodically feeding insectivore to minimize urinary water loss.

EFFECT OF HYPOXIA ON CEREBRAL ANAEROBIC GLYCOLYSIS IN THE HIBERNATOR AND INFANT OR ADULT HOMEOTHERM.

Abstract 1. 1. Rates of anaerobic glycolysis were compared in cerebral tissue from hypoxic infant rats, adult rats and active or hibernating ground squirrels ( Citellus tridecemlineatus ). 2. 2. An increased capacity for anaerobic energy production contributes to the hypoxic tolerance exhibited by hibernating mammals and infant homeotherms.