Linked Life Data

2869877

Source:http://linkedlifedata.com/resource/pubmed/id/2869877

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1986-4-25
pubmed:abstractText
Thermoregulatory capacities of 51 reindeer calves (Rangifer tarandus tarandus L.) aged 1-35 days were studied at -26.5 to +35.0 degrees C ambient temperatures at Kaamanen reindeer research station, Finland (69 degrees 10' N) during calving periods in May 1981 and May-July 1982. The newborn calves aged 1-4 days maintained a high body temperature (Tre) (mean +40.2 degrees C) even at the lowest experimental temperature of -22.5 degrees C by increasing their metabolic rate five-fold above the level at +11.0 degrees C. Heat production of the new-born calves was largely based on the metabolism of brown adipose tissue, stimulated by cold-induced discharge of the sympathetic nervous transmitter, noradrenaline (NA). Sensitivity of the calves to exogenous NA disappeared during the first 3-4 weeks of life. Thermal conductance of the calves was low at low ambient temperatures, but rose strongly as Ta increased above +10 degrees C. The extensive peripheral cooling, especially in the feet, was demonstrated in the calves aged 1-10 days. The lowest foot temperature (+10.5 degrees C) was measured in a 4-day-old calf at -14.5 degrees C. Slight shivering thermogenesis was recorded in the calves aged 1-4 days and occasionally in the older calves at low values of Ta. Shivering appears to be a reserve mechanism against severe cold. At about +20 degrees C and above the calves increased their Tre (approximately 1 degree C), oxygen consumption and heart rate. In the newborn calves oxygen consumption rose four- to five-fold and in 1-month-old calves about two-fold. Fast growing calves (maximum 400 g/day) appear to be more stressed by heat than by cold exposure.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0300-9629
pubmed:author
pubmed:issnType
Print
pubmed:volume
83
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
371-86
pubmed:dateRevised
2008-10-30
pubmed:meshHeading
pubmed:year
1986
pubmed:articleTitle
The influence of ambient temperature on metabolism and body temperature of newborn and growing reindeer calves (Rangifer tarandus tarandus L.).
pubmed:publicationType
Journal Article, Comparative Study