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Biomedical subjects

D M Jenkinson

Publications and source records attributed to D M Jenkinson.

At least 73 records · Page 4Linked to original sources
PubMed1971

Studies on the nature of sweat gland 'fatigue' in the goat.

1. The nature of the ;fatigue' of sweating that occurs in the goat upon exposure to environmental conditions of 40 degrees C/26 degrees C (dry bulb/wet bulb) has been examined.2. Heat exposure activated all the sweat glands and the decrement in sweating which occurred was due to a decline in the amount of sweat produced by each gland.3. The decline in sweating activity was associated with a decrease in sweat gland volume and a thickening of the glandular wall. The restoration of sweat gland function took approximately 5-6 hr after removing the animal from the hot environment but the restoration of sweat gland volume took longer.4. The volume of sweat produced was greater than the decrease in sweat gland volume and it is concluded that ;fatigue' is due to the rate of expulsion exceeding the rate of sweat production.5. Repeated intravenous injections of adrenaline at 40 degrees C resulted in a decline in sweat output and reduced the normal glandular response to heat exposure.

Animals↗
PubMed1968

Adipose tissue and heat production in the new-born ox (Bos taurus).

1. A histological examination of adipose tissue from 1- and 6-day-old calves showed a structure typical of white adipose tissue and no evidence of brown adipose tissue.2. Infusion of noradrenaline (1.0 mug/kg.min I.V.) into 1-to 6-day-old calves affected heart rate and respiratory rate but did not increase heat production, rectal temperature, skin temperature or skin evaporative loss.3. Cold exposure led to shivering and an increased oxygen consumption in the 6-day-old calf.4. Blood samples taken from 6-day-old calves in the cold (-1 degrees C) appeared to have a higher proportion of unesterified fatty acids in the total blood lipid than samples taken in an environment of 20 degrees C, but no change in fatty acid composition was found.5. It has been concluded that there is no non-shivering thermogenesis in the young calf.

Adipose Tissue↗