Premium
Adipose tissue and heat production in the new‐born ox ( Bos taurus )
Author(s) -
Jenkinson D. McEwan,
Noble R. C.,
Thompson G. E.
Publication year - 1968
Publication title -
the journal of physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.802
H-Index - 240
eISSN - 1469-7793
pISSN - 0022-3751
DOI - 10.1113/jphysiol.1968.sp008479
Subject(s) - shivering , adipose tissue , brown adipose tissue , thermogenesis , white adipose tissue , endocrinology , medicine , fatty acid , chemistry , respiratory system , zoology , biology , biochemistry , physiology
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 μg/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° C) appeared to have a higher proportion of unesterified fatty acids in the total blood lipid than samples taken in an environment of 20° 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.