Studies on the adaptability of three breeds of sheep to a tropical environment modified by altitude IV. Role of the fleece in thermoregulation in German Merino ewes

1960 ◽  
Vol 55 (3) ◽  
pp. 311-315
Author(s):  
R. B. Symington
Keyword(s):  
Thermal Stress ◽  
Body Temperature ◽  
Respiratory Rate ◽  
Skin Temperature ◽  
Rectal Temperature ◽  
High Heat ◽  
Diurnal Fluctuation ◽  
Body Temperature Regulation ◽  
Southern Rhodesia

The influence of fleece on thermoregulation in German Merino ewes was investigated in Rhodesia. Comparative heat tolerances of Persian Blackhead, indigenous Native and shorn and unshorn Merino ewes were obtained during the hottest month of the year in Northern Rhodesia. The main thermolytic responses in unshorn, partially shorn and completely shorn Merino ewes were measured at 7.0 a.m.; 10.0 a.m.; 1.0 p.m. and 4.0 p.m. during April in Southern Rhodesia.1. Unshorn Merino ewes showed more and shorn Merino ewes less effective body temperature regulation than Persian or Native ewes. High heat tolerance in unshorn Merinos was due primarily to insulation by the fleece and not to more efficient physiological thermolysis than in hair breeds. No ewe showed signs of undue thermal stress and feed intake was not affected by heat.2. Increases in rectal temperature and respiratory rate between 7.0 a.m. and 1.0 p.m. of Merinos in Southern Rhodesia were related inversely to fleece length. Body temperature did not differ significantly at 1.0 p.m. owing to differential rates of increase in respiratory rate.3. Magnitude of the diurnal fluctuation in skin temperature was also related inversely to fleece length. Partially shorn ewes, however, began with and maintained highest skin temperature through the heat of the day. In all groups skin temperature fell after 10.0 a.m. although ambient temperature continued to rise. This fall could not be attributed to sweating since moisture secretion declined simultaneously.

Observations on the effect of salicylate in fever and the regulation of body temperature against cold

1976 ◽  
Vol 54 (2) ◽  
pp. 101-106 ◽  
Author(s):  
Q. J. Pittman ◽  
W. L. Veale ◽  
K. E. Cooper
Keyword(s):  
Body Temperature ◽  
Skin Temperature ◽  
Rectal Temperature ◽  
Heat Production ◽  
Intravenous Infusion ◽  
Sodium Salicylate ◽  
Single Injection ◽  
Continuous Intravenous Infusion ◽  
Skin Temperatures

Prostaglandins appear to be mediators, within the hypothalamus, of heat production and conservation during fever. We have investigated a possible role of prostaglandins in the nonfebrile rabbit during thermoregulation in the cold. Shorn rabbits were placed in an environment of 20 °C, and rectal and ear skin temperatures, shivering and respiratory rates were measured. A continuous intravenous infusion of leucocyte pyrogen was given to establish a constant fever of approximately 1 °C, and after observation of a stable febrile temperature for 90 min, a single injection of 300 mg of sodium salicylate, followed by a 1.5 mg/min infusion was then given. After the salicylate infusion was begun, rectal temperature began to fall, and reached nonfebrile levels within 90 min. Shivering activity ceased, respiratory rates increased, and in two animals, ear skin temperature increased. When these same rabbits were placed in an environment of 10 °C, at a time they were not febrile, and an identical amount of salicylate was given, rectal and ear skin temperatures, shivering and respiratory rates did not change. These results indicate that prostaglandins do not appear to be involved in heat production and conservation in the nonfebrile rabbit.

Acclimatization of calves to a hot humid environment

1959 ◽  
Vol 52 (3) ◽  
pp. 305-312 ◽  
Author(s):  
W. Bianca
Keyword(s):  
Heart Rate ◽  
Body Temperature ◽  
Respiratory Rate ◽  
Skin Temperature ◽  
Rectal Temperature ◽  
Heat Production ◽  
Metabolic Heat ◽  
Hot Environment ◽  
Humid Environment ◽  
Physiological Reactions

1. Three calves were exposed in a climatic room to an environment of 40° C. dry-bulb and 38° C. wet-bulb temperature for up to 110 min. each day for 1-2 weeks.2. These exposures produced progressive changes in the physiological reactions of the animals to heat:(a) Rectal temperature and skin temperature (for a given time of exposure) declined. In consequence there was a marked increase in the tolerance time, i.e. in the time for which the animals could withstand the hot environment before reaching a rectal temperature of 42° C.(b) Respiratory rate rose earlier and assumed higher levels (for given levels of body temperature).(c) Heart rate decreased markedly.3. These changes are discussed in relation to heat loss and heat production and have been interpreted as reflecting chiefly a reduction in the metabolic heat production of the animals.

A study of heat tolerance of grade Australian Illawarra Shorthorn cows during early lactation.

1953 ◽  
Vol 4 (2) ◽  
pp. 224 ◽  
Author(s):  
KW Robinson ◽  
GH Klemm
Keyword(s):  
Body Temperature ◽  
Respiratory Rate ◽  
Skin Temperature ◽  
Pulse Rate ◽  
Heat Tolerance ◽  
Rectal Temperature ◽  
Water Loss ◽  
Atmospheric Conditions ◽  
Temperature Pulse ◽  
Evaporative Loss

Four grade Australian Illawarra Shorthorn cows, aged 3 years, were exposed for 7 hr. twice a week to each of several atmospheres having dry-bulb temperatures ranging from 86° to 108.5°F. and absolute humidities ranging from 8 to 16 g./cu. ft. The following reactions were studied: rectal temperature, pulse rate, respiratory rate, evaporative loss, skin temperature, and behaviour. Average 9 a.m. ante-room rectal temperature reading was 101.5 ± 1.29°F. Dry-bulb temperatures of 95°F. and above caused a noticeable rise in rectal temperature and rise in body temperature paralleled rise in humidity. Humidity had a greater effect on the animal than dry-bulb temperature. Pulse rate was essentially unaffected by rise in temperature. Environmental conditions markedly influenced respiratory rate. On exposure to heat, the rate increased considerably before any rise in rectal temperature was apparent. When dry-bulb temperature increased, there was a parallel rise of evaporative loss with rise in respiratory rate. Humidity had little effect on water loss. Comparisons of the reactions of Australian Illawarra Shorthorn cows were made with four Jersey cows of similar age and lactation, exposed to atmospheric conditions similar to those observed by Riek and Lee two years previously. The following points were brought out: (i) The heat tolerance is greater in Jerseys with all combinations of dry- and wet-bulb temperatures. (ii) There is no significant change in pulse rate with breed. (iii) Respiratory rates are similar in the two breeds until the highest temperatures are reached, when that of the Illawarra Shorthorn increases above that of the Jersey. (iv) A greater increase in water loss occurs in the Jersey. (v) There is a larger body temperature-skin temperature gradient in the IIIawarra Shorthorn.

scholarly journals INVESTIGATION OF THE THERMAL STATE OF ATHLETES IN NATURAL HOT CLIMATE

2019 ◽  
Vol 96 (9) ◽  
pp. 896-899
Author(s):  
S. M. Rasinkin ◽  
Viktoriya V. Petrova ◽  
M. M. Bogomolova ◽  
E. P. Gorbaneva ◽  
A. G. Kamchatnikov ◽  
...  
Keyword(s):  
Body Temperature ◽  
Skin Temperature ◽  
Rectal Temperature ◽  
Thermal State ◽  
Subjective Evaluation ◽  
Climate Indices ◽  
Hot Climate ◽  
The Cross ◽  
Average Skin ◽  
Average Body

The article presents results of a study of the thermal stability in athletes during specific activities in hot climate. This happened on a training camp at the sports center, located in the district Sredneakhtubinsky of the Volgograd region with the registration of climate indices. The study was conducted in July at an effective temperature +44,6° - +45,4°C. The study involved 6 athletes, representatives of athletics, sports category on the following candidate for master of sports. During the endurance, training (cross) in athletes showed a significant increase in the rectal temperature (RT), average skin temperature (AST), average body temperature (ABT) against the background of the gain in the heart rate. During the training as "repeated cuts", the increase in indices of the thermal state in athletes also persisted, but their values were significantly lower than on the cross. The comparison of the dynamics of indices of the thermal state with the level of sports skills of each athlete showed the following features: the smallest gain in the rectal temperature, average skin temperature and average body temperature observed in cross-country race was observed in sportsman, whose level of training coach the evaluated as a minimal in the group. The highest gain in indices of the thermal state at the cross happened in the athlete with an average fitness level. Optimal gain in such indices as RT, AST and ABT was observed in the most prepared athlete. There was revealed a high level of adaptationness of athletes to the exposure to high temperatures. This is confirmed by the data of the evaluation of dynamics of subjective evaluation of warmth sense modality in athletes during the study period.

Effect of continuous cold exposure on nocturnal body temperatures of man

1959 ◽  
Vol 14 (1) ◽  
pp. 43-45 ◽  
Author(s):  
M. B. Kreider ◽  
P. F. Iampietro ◽  
E. R. Buskirk ◽  
David E. Bass
Keyword(s):  
Body Temperature ◽  
Cold Stress ◽  
Skin Temperature ◽  
Rectal Temperature ◽  
Cold Exposure ◽  
Control Period ◽  
Cold Period ◽  
Body Temperatures ◽  
Temperature Responses

Effects of continuous cold stress on 24-hour patterns of body temperature were studied in five men. Cold stress consisted in living at 15.6℃ (60℉) for 14 days wearing only shorts. The cold period was preceded and followed by 2 weeks at 26.7℃ (80℉). Activity (minimal) and diet were the same for all periods. One blanket was used at night. Rectal temperature (Tr) and skin temperature (Ts) were measured. Tr during sleep fell more rapidly and to lower values during cold exposure (35.6℃) than during the control period (36.1℃). Ts during sleep was slightly lower in the cold than in the control period; also, Ts did not exhibit the gradual drop characteristic of sleep in the control period. Comparison of Tr and Ts between early and later cold days revealed the following differences: a) nocturnal Tr fell to lower levels on the later cold days; b) nocturnal toe temperatures were 15℃ (27℉) higher on the later cold days. The arch temperatures followed the same pattern as the toes. No significant differences were found in daytime temperatures between early and later cold days. The data suggest that evidence for acclimatization to cold in terms of altered body temperature responses may be fruitfully sought in responses during rewarming and/or sleep. Submitted on September 19, 1958

Tolerance to extreme cold at altitude in a Nepalese pilgrim

1963 ◽  
Vol 18 (6) ◽  
pp. 1234-1238 ◽  
Author(s):  
L. G. C. E. Pugh
Keyword(s):  
Body Temperature ◽  
Skin Temperature ◽  
Rectal Temperature ◽  
Cold Water ◽  
Subcutaneous Fat ◽  
Subcutaneous Fat Thickness ◽  
Fat Thickness ◽  
Extreme Cold

Body temperature and respiratory experiments are reported on a Nepalese pilgrim who survived, uninjured, 4 days of exposure at 15,000–17,500 ft in midwinter, wearing only light clothing and no shoes or gloves. His resistance to cold depended on elevation of metabolism and, unlike tolerance of immersion in cold water, was not related to subcutaneous fat thickness. He slept soundly in spite of the cold and so did not become exhausted. In 3–4-hr experiments at o C (clothed), rectal temperature and skin temperature over the trunk showed only minor changes; hand and foot temperatures did not fall below 10–13 C. Maintenance of body temperature was accounted for by elevation of metabolism. survival in cold Submitted on February 19, 1963

Studies on the adaptability of three breeds of sheep to a tropical environment modified by altitude II. Responses in body, skin and coat temperatures, cardio-respiratory frequencies and rate of moisture secretion of ewes to the diurnal fluctuation in ambient temperature during the hottest part of the year

1960 ◽  
Vol 55 (3) ◽  
pp. 295-302 ◽  
Author(s):  
R. B. Symington
Keyword(s):  
Body Temperature ◽  
Ambient Temperature ◽  
Skin Temperature ◽  
Skin Surface ◽  
Diurnal Fluctuation ◽  
Body Temperatures ◽  
Solar Insolation ◽  
Air Temperatures ◽  
Insensible Perspiration ◽  
Artificial Heat

Responses in body, skin and coat temperatures, cardio-respiratory frequencies and rate of moisture secretion of ewes of three breeds to the diurnal fluctuation in ambient temperature were recorded in the presence and absence of drinking water during the hottest part of the Rhodesian year.1. At 7.0 a.m. body temperatures were: Merino 102·8° F.; Persian 102·2° F. and Native 101·5° F. Between 7·0 a.m. and 1·0 p.m. body temperature rose almost equally in Persians and Natives and fell slightly in Merinos. Change in body temperature between 7.0 a.m. and 1.0 p.m. was not affected significantly by availability of water nor age of ewe, but varied with type of thermal burden (i.e. solar insolation only v. solar insolation plus artificial heat) when water was not available. Although air temperature fell towards late afternoon body temperature of Merinos and Natives rose appreciably, that of Persians only slightly.2. At 7·0 a.m. respiratory rates were (cyc./min.): Merino 59·6; Persian 43·0; Native 29·9. Increase in rate of respiration was the main thermolytic mechanism in all breeds. Merinos had a lower threshold of respiratory response to rising ambient temperature than either hair breed but increase in rate of respiration between 7.0 a.m. and 1.0 p.m. did not differ significantly with breed or age.3. No breed appeared to use the peripheral blood system in thermoregulation. Cardio-frequency, as a measure of this blood flow, remained almost constant with a slight tendency to fall with rise in ambient temperature.4. In all breeds skin temperature was related to ambient and body temperatures; consequently the diurnal fluctuation in skin temperature differed in wool and hair breeds. When thermal burden was greatest Merino skin temperature fell, that of hair breeds did not.Except at 11.0 a.m. there was a gradient between rectal, skin and air temperatures. Direct elimination of heat was thus possible for 23 hr. each day.5. In hair breeds moisture secretion depended on insensible perspiration; consequently, rate of moisture secretion changed with body and air temperatures. In Merinos moisture for skin surface evaporation was provided by sensible and insensible perspiration. Natives may be able to sweat at temperatures higher than those recorded but it is unlikely Persians have a sweating mechanism.6. In all breeds coat temperature was related closely to ambient temperature and changes in solar conditions evoked immediate response in coat temperature. Merino fleece apparently stabilized skin temperature whereas Persian and Native hair did not.

Influence of water temperature on oxygen uptake by swimming rats

1964 ◽  
Vol 19 (6) ◽  
pp. 1215-1218 ◽  
Author(s):  
Mary Ann Baker ◽  
Steven M. Horvath
Keyword(s):  
Thermal Stress ◽  
Body Temperature ◽  
Oxygen Uptake ◽  
Rectal Temperature ◽  
Hot Water ◽  
Swimming Time ◽  
Cold Environments ◽  
Influence Of Water ◽  
The Mean ◽  
Neutral Water

Oxygen uptake and rectal temperature of ten rats forced to swim to exhaustion or for 45 min in cold, hot, and thermoneutral water were measured during swimming. In 20 C water rats swam for 12.6 min and had a final rectal temperature of 26.9 C. In 42 C water the mean swimming time was 14.1 min and the final rectal temperature was 42.6 C. All rats swam for 45 min in water of 37 C, and the final rectal temperature was not different from the preswim temperature. Oxygen uptake during swimming in 37 C water rose and stabilized at a rate of about three times basal in a pattern suggesting that the swimming work was moderate. Animals swimming in cold and hot water were exhausted before their oxygen uptakes stabilized, but the increasing oxygen uptakes during the early parts of these swims were similar to that in neutral water. It appeared that while the metabolic rate was adjusted to the level of work and was not greatly affected by severe changes in body temperature, alterations in body temperature profoundly influenced the duration of work in the hot or cold environments. exercise and thermal stress; exercise metabolism Submitted on March 23, 1964

Body temperature, respiration and pulse rate in Corriedale, Marwari and Magra sheep in the Rajasthan desert

1979 ◽  
Vol 93 (3) ◽  
pp. 587-591 ◽  
Author(s):  
J. P. Mittal ◽  
P. K. Ghosh
Keyword(s):  
Body Temperature ◽  
Respiratory Rate ◽  
Pulse Rate ◽  
Rectal Temperature ◽  
Western India ◽  
Cross Breeding ◽  
Desert Areas ◽  
Free Grazing ◽  
North Western ◽  
Local Stock

SUMMARYDuring summer the morning (08.00 h) to afternoon (15.00 h) increases in rectal temperature, respiratory rate and pulse rate of free grazing Marwari and Magra sheep (rams) of the desert areas of north-western India were compared with those of Corriedale rams, which are being imported into India to improve the productivity of local stock through cross-breeding. Basal (morning) values for all three measurements were similar in the three breeds. While the afternoon values in respect of all three characters were significantly higher than the morning values in all the breeds, the increases were greatest in the Corriedales.

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