Upper lethal temperatures of the pelecypod Modiolus demissus in relation to declining environmental temperatures

1972 ◽  
Vol 50 (5) ◽  
pp. 523-527 ◽  
Author(s):  
D. L. Waugh
Keyword(s):  
Ambient Temperature ◽  
Environmental Temperature ◽  
Lethal Temperature ◽  
Winter Habitat ◽  
Lethal Temperatures ◽  
Thermal Acclimatization ◽  
Autumn And Winter ◽  
Environmental Temperatures ◽  
Accurate Reflection ◽  
Ribbed Mussel

Determinations of 24-h upper lethal temperatures of the ribbed mussel Modiolus demissus (Dillwyn) in relation to declining autumn and winter habitat temperatures show effective thermal acclimatization. Upper lethal temperatures ranged from 39.48 ± 0.33C to 37.67 ± 0.08C and the descending range of mean monthly environmental temperature was from 25C to −1.1C. Environmental and test salinity ranged from 28 to 30‰.The regression of lethal temperature on acclimatization temperature is significant when a direct correlation (concomitant) is made between ambient temperature and lethal temperature. Thus, current ambient temperature is an accurate reflection of acclimatization in this species.

scholarly journals The Adaptability of Mice to High Environmental Temperatures

1958 ◽  
Vol 35 (4) ◽  
pp. 892-901
Author(s):  
G. AINSWORTH HARRISON
Keyword(s):  
Survival Time ◽  
Heat Tolerance ◽  
Opposite Direction ◽  
Environmental Temperature ◽  
Lethal Temperature ◽  
F1 Hybrid ◽  
Hot Environment ◽  
Lower Heat ◽  
Environmental Temperatures ◽  
Hybrid Mice

1. C57xRIII F1 hybrid mice reared at 32° C. D.B., 29° C. W.B., from 3 to 8 weeks of age, survive longer at 41·7° C. D.B., 29·4° C. W.B., than litter-mates reared at 20° C. D.B., 16° C. W.B. 2. The transference of animals from the hot environment to the cooler one 48 hr. before they are exposed to the lethal temperature has little or no effect on their heat tolerance; but transference in the opposite direction greatly increases survival time. 3. Mice whose tails have been amputated 5 weeks before they are exposed to the lethal temperature have a lower heat tolerance than normal animals. 4. The total loss in weight of an animal exposed to the lethal temperature is independent of the environmental temperature at which it has been reared; but heat-acclimatized animals lose weight less rapidly than control ones. 5. It is concluded that at least some of the changes, both physiological and morphological, which occur when mice are reared at high temperatures, are in their over-all effect adaptive.

Upper Lethal Temperatures in Relation to Osmotic Stress in the Ribbed Mussel Modiolus demissus

1971 ◽  
Vol 28 (4) ◽  
pp. 527-532 ◽  
Author(s):  
D. L. Waugh ◽  
E. T. Garside
Keyword(s):  
Osmotic Stress ◽  
Thermal Acclimation ◽  
Test Medium ◽  
Lethal Temperature ◽  
Lethal Temperatures ◽  
Ribbed Mussels ◽  
Osmotic Acclimation ◽  
The Mean ◽  
Ambient Salinity ◽  
Ribbed Mussel

Upper lethal temperatures for the ribbed mussel Modiolus demissus (Dillwyn) were determined for thermal acclimations of 15.0, 20.0, and 25.0 C and osmotic acclimations at 5, 15, and 28‰ S, which yielded nine combinations. These upper lethal temperatures for 1440 min exposure ranged from 38.42 to 40.18 C, generally paralleling increases in thermal acclimation. The upper lethal temperature within any thermal acclimation decreased as the salinity of the bioassay departed from the appropriate level of osmotic acclimation. Depression of the upper lethal temperature was more pronounced in the test medium of 5‰ S. The shift from osmoconformity to osmoregulation, which occurs in this species when the ambient salinity is reduced to 350 mosmols (approximately 10‰ S) apparently extends the metabolic load or stress relative to that induced by similar temperatures in higher levels of salinity. Order of death in any bioassay was independent of size expressed as length, and specific sex.The upper lethal temperatures are higher than the mean temperature of the substrate of the collecting site during the warmest period of the summer, but are approximately the same as the maximum substrate temperature during that period. Survival of ribbed mussels in such potentially lethal conditions is explained by the shorter intermittent natural exposures than those employed in the bioassays.

Dealing with hot rocky environments: Critical thermal maxima and locomotor performance in Leptodactylus lithonaetes (Anura: Leptodactylidae)

2019 ◽  
pp. 155-161 ◽  
Author(s):  
Ivan Beltran
Keyword(s):  
Environmental Temperature ◽  
Extreme Temperature ◽  
Effect Of Temperature ◽  
Maximum Speed ◽  
Locomotor Performance ◽  
Extreme Temperatures ◽  
Physiological Limits ◽  
Fitness Consequences ◽  
Thermal Maximum ◽  
Environmental Temperatures

Environmental temperature has fitness consequences on ectotherm development, ecology and behaviour. Amphibians are especially vulnerable because thermoregulation often trades with appropriate water balance. Although substantial research has evaluated the effect of temperature in amphibian locomotion and physiological limits, there is little information about amphibians living under extreme temperature conditions. Leptodactylus lithonaetes is a frog allegedly specialised to forage and breed on dark granitic outcrops and associated puddles, which reach environmental temperatures well above 40 ˚C. Adults can select thermally favourable microhabitats during the day while tadpoles are constrained to rock puddles and associated temperature fluctuations; we thus established microhabitat temperatures and tested whether the critical thermal maximum (CTmax) of L. lithonaetes is higher in tadpoles compared to adults. In addition, we evaluated the effect of water temperature on locomotor performance of tadpoles. Contrary to our expectations, puddle temperatures were comparable and even lower than those temperatures measured in the microhabitats used by adults in the daytime. Nonetheless, the CTmax was 42.3 ˚C for tadpoles and 39.7 ˚C for adults. Regarding locomotor performance, maximum speed and maximum distance travelled by tadpoles peaked around 34 ˚C, approximately 1 ˚C below the maximum puddle temperatures registered in the puddles. In conclusion, L. lithonaetes tadpoles have a higher CTmax compared to adults, suggesting a longer exposure to extreme temperatures that lead to maintain their physiological performance at high temperatures. We suggest that these conditions are adaptations to face the strong selection forces driven by this granitic habitat.

The effects of environmental temperature and method of feeding on the performance and carcass composition of bacon pigs

1967 ◽  
Vol 9 (2) ◽  
pp. 209-218 ◽  
Author(s):  
D. W. Holme ◽  
W. E. Coey
Keyword(s):  
Environmental Temperature ◽  
Average Daily Gain ◽  
Carcass Composition ◽  
Restricted Feeding ◽  
Feed Conversion ◽  
Feeding Method ◽  
Feeding Regimes ◽  
Higher Temperature ◽  
Ad Libitum ◽  
Environmental Temperatures

A trial designed to investigate the effects of two environmental temperatures, three feeding regimes and the interactions between them is described. A temperature of 72° F. was better than one of 54° F. for bacon pigs between 40 lb. and 200 lb. weight. The higher temperature resulted in faster growth, more efficient feed conversion and increased length of carcass. Other carcass characteristics were not significantly altered. Ad libitum feeding resulted in faster growth and fatter carcasses than restricted feeding, but did not have a significant effect on efficiency of feed conversion. When feed intake was restricted, feeding pigs once daily or twice daily resulted in similar performance and carcass composition.There was a significant interaction between environmental temperature and feeding method for average daily gain in that pigs fed ad libitum grew faster at the low temperature and pigs fed restricted amounts of feed grew faster at the high temperature. No other interaction reached significant levels.

SOME LETHAL TEMPERATURE RELATIONS OF TWO MINNOWS OF THE GENUS CHROSOMUS

1966 ◽  
Vol 44 (3) ◽  
pp. 349-364 ◽  
Author(s):  
Albert V. Tyler
Keyword(s):  
Thermal Shock ◽  
High Temperatures ◽  
The Other ◽  
Lethal Temperature ◽  
Lethal Temperatures ◽  
Equal Temperature

The resistance and tolerance of Chrosomus eos and Chrosomus neogaeus to high temperatures were examined. Tests were conducted with C. neogaeus in winter and with C. eos in winter and summer. For both species, death at high temperatures could be separated into three lethal patterns or "effects". The first effect seemed to be associated, at least in part, with thermal shock. Factors generating the other effects were not apparent.Both species showed about the same degree of tolerance and resistance to high temperatures when they were acclimated to 15 °C or higher. At 9 °C, C. eos was less tolerant to high lethal temperatures than was C. neogaeus.When equal temperature acclimations were compared, C. eos was more resistant to high lethal temperatures in summer than in winter.

Effect of ambient temperature on protein breakdown during prolonged exercise

1988 ◽  
Vol 64 (2) ◽  
pp. 550-555 ◽  
Author(s):  
D. G. Dolny ◽  
P. W. Lemon
Keyword(s):  
Ambient Temperature ◽  
Prolonged Exercise ◽  
Respiratory Exchange Ratio ◽  
Protein Breakdown ◽  
Protein Utilization ◽  
Post Exercise ◽  
Ambient Temperatures ◽  
Environmental Temperatures ◽  
Male Subjects ◽  
H Protein

Male subjects (n = 8) cycled for 90 min in 5, 20, and 30 degrees C environments. Rectal (Tre), chest, and thigh temperatures, O2 consumption (VO2), respiratory exchange ratio (R), and venous concentrations of glucose, free fatty acids (FFA), urea N, lactic acid (LA), norepinephrine (NE), epinephrine (E), and cortisol (C) were measured before, during, and after exercise. Urea N excretion was measured in 72 h of nonexercise, in 72 h of exercise (exercise day + 2 post-exercise days) urine samples, and in exercise sweat. Calculated 72-h protein utilization (means +/- SE) was significantly greater (P less than 0.05) for the 5 (86.9 +/- 27.1 g) and 20 (82.9 +/- 22.7 g) compared with 30 degrees C (34.01 +/- 19.1 g) trial. Regardless of ambient temperature exercise increased the venous concentration of C, E, and NE. These catabolic hormones were greatest in 5, lowest in 20, and intermediate in 30 degrees C. Exercise Tre and VO2 were greatest in the 30 degrees C environment. Venous FFA concentration was significantly higher and R significantly lower in 5 vs. 20 or 30 degrees C, and venous LA concentration was significantly greater in 30 vs. 20 or 5 degrees C. Although these results indicate that exercise protein breakdown is affected by ambient temperatures, the mechanism of action is not due solely to circulating NE, E, and C. Differences in venous FFA and LA across environmental temperatures suggest that alterations in carbohydrate and fat metabolism may have contributed to the observed variable protein utilization.

Influence of the environmental temperature on the post-partum testosterone surge in the rat

1987 ◽  
Vol 115 (4) ◽  
pp. 478-482 ◽  
Author(s):  
J. Roffi ◽  
F. Chami ◽  
P. Corbier ◽  
D. A. Edwards
Keyword(s):  
Ambient Temperature ◽  
Environmental Temperature ◽  
Post Partum ◽  
Serum Testosterone ◽  
The Body ◽  
Male Rats ◽  
Effect Of Temperature ◽  
Male Rat ◽  
Foster Mother ◽  
The Central Nervous System

Abstract. In the neonatal male rat, a rapid and transient increase in serum testosterone occurs about 2 h after birth. This post-partum testosterone surge (PPTS) has been implicated in the masculinization and defeminization of the central nervous system. The present study shows that environmental temperature can have a profound influence on the PPTS. Male rats were delivered from their mothers by caesarean section on day 22 of gestation. Immediately thereafter, neonatal males were placed at an ambient temperature of either 18, 21, 24 or 30°C. With 2 h of exposure, the body temperature was in close correspondence with the ambient temperature. The PPTS was clearly abolished in the pups exposed for 2 h at either 18 or 21°C. The effect of temperature was reversible: by placing pups at either 18 or 21°C for 2 h after delivery, and then rewarming by placing them with a foster mother, the PPTS was delayed until 4 h after birth, i.e. 2 h after the beginning of rewarming. Thus, environmental cooling appears to retard the development of neural and/or endocrine systems mediating the PPTS. Aberrant maternal care which would produce substantial cooling of the male pups would be expected to affect the PPTS, which in turn might affect the sexuality of male progeny.

Aspects of the Physiology of Terrestrial Life in Amphibious Fishes

1969 ◽  
Vol 50 (1) ◽  
pp. 141-149 ◽  
Author(s):  
MALCOLM S. GORDON ◽  
INGE BOËTIUS ◽  
DAVID H. EVANS ◽  
ROSEMARY McCARTHY ◽  
LARRY C. OGLESBY
Keyword(s):  
Thermal Stresses ◽  
Severe Dehydration ◽  
Evaporative Water ◽  
Lethal Temperatures ◽  
Physiological Adaptations ◽  
Urea Production ◽  
Terrestrial Life ◽  
Production Increase ◽  
Amphibious Fishes ◽  
Environmental Temperatures

1. A study has been carried out of major aspects of the physiological adaptations for terrestrial life possessed by the amphibious mudskipper fish, Periophthalmus sobrinus, on the island of Nosy Bé, Madagascar. 2. These fish can survive for approximately 1½ days out of water, if not exposed to severe dehydration or thermal stresses. Evaporative water-loss rates while out of water are relatively low. Upper lethal temperatures are only a few degrees above normal midday environmental temperatures. 3. These fish lack the symptoms of the ‘diving syndrome’. Metabolic rates (oxygen consumption), heart rates, and blood lactic acid concentrations are not affected by shifts of fish between water and air. 4. Rates of ammonia and urea production increase in fish out of water. The ratio of urea/ammonia also increases. 5. The generality of the results, also their physiological significance, are discussed.

scholarly journals Effects of 7°C environmental temperature acclimation during a 3-week training period

2020 ◽  
Vol 128 (4) ◽  
pp. 768-777
Author(s):  
Robert Shute ◽  
Katherine Marshall ◽  
Megan Opichka ◽  
Halee Schnitzler ◽  
Brent Ruby ◽  
...  
Keyword(s):  
Room Temperature ◽  
Environmental Temperature ◽  
Cellular Signaling ◽  
Temperature Acclimation ◽  
Peroxisome Proliferator ◽  
Peroxisome Proliferator Activated Receptor ◽  
Training Adaptations ◽  
Before And After ◽  
The Impact ◽  
Environmental Temperatures

Cold environmental temperatures during exercise and recovery alter the acute response to cellular signaling and training adaptations. Approximately 3 wk is required for cold temperature acclimation to occur. To determine the impact of cold environmental temperature on training adaptations, fitness measurements, and aerobic performance, two groups of 12 untrained male subjects completed 1 h of cycling in 16 temperature acclimation sessions in either a 7°C or 20°C environmental temperature. Fitness assessments before and after acclimation occurred at standard room temperature. Muscle biopsies were taken from the vastus lateralis muscle before and after training to assess molecular markers related to mitochondrial development. Peroxisome proliferator-activated receptor-γ coactivator 1α ( PGC-1α) mRNA was higher in 7°C than in 20°C in response to acute exercise before training ( P = 0.012) but not after training ( P = 0.813). PGC-1α mRNA was lower after training ( P < 0.001). BNIP3 was lower after training in the 7°C than in the 20°C group ( P = 0.017) but not before training ( P = 0.549). No other differences occurred between temperature groups in VEGF, ERRα, NRF1, NRF2, TFAM, PINK1, Parkin, or BNIP3L mRNAs ( P > 0.05). PGC-1α protein and mtDNA were not different before training, after training, or between temperatures ( P > 0.05). Cycling power increased during the daily training ( P < 0.001) but was not different between temperatures ( P = 0.169). V̇o2peak increased with training ( P < 0.001) but was not different between temperature groups ( P = 0.460). These data indicate that a 3-wk period of acclimation/training in cold environmental temperatures alters PGC-1α gene expression acutely but this difference is not manifested in a greater increase in V̇o2peak and is dissipated as acclimation takes place. NEW & NOTEWORTHY This study examines the adaptive response of cellular signaling during exercise in cold environmental temperatures. We demonstrate that peroxisome proliferator-activated receptor-γ coactivator 1α mRNA is different between cold and room temperature environments before training but after training this difference no longer exists. This initial difference in transcriptional response between temperatures does not lead to differences in performance measures or increases in protein or mitochondria.

LOW-TEMPERATURE ENVIRONMENTAL STRESS AND THE METABOLISM OF VITAMIN A IN THE RAT

1962 ◽  
Vol 40 (1) ◽  
pp. 491-499 ◽  
Author(s):  
W. E. J. Phillips
Keyword(s):  
Low Temperature ◽  
Vitamin A ◽  
Environmental Stress ◽  
Room Temperature ◽  
Environmental Temperature ◽  
Sprague Dawley ◽  
Vitamin A Metabolism ◽  
Environmental Temperatures

Carotene and vitamin A metabolism in the rat were studied at two environmental temperatures. The utilization of carotene is greater in animals maintained at a low environmental temperature (2°) than at room temperature (22°). This occurred within a period of 3 days. Both the hepatic storage and the rate of metabolism of orally administered vitamin A were unaffected by environmental temperature. The response of Wistar and Sprague–Dawley strains was similar.

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