Body temperature and resistance to cooling in growing pine voles

Abstract

M arek GĘBCZYŃSKI G ębczyński M., 1981: Body te m p e ra tu re and resistan ce to cooling in grow ing pin e voles. A cta theriol., 26, 34: 495-499 [W ith 1 T able].Body te m p e ra tu re in the pine vole Pitymys subterraneus (de S elys-L ongcham ps, 1836) is about 33°C a t b irth , b u t reach es 38° b y th e fo u rth w eek of life. Increase in body te m p e ra tu re is m ost rap id d u rin g the firs t w eek of life. Its value does n o t v ary b etw een th e 7th and 12th day of life. R eaction to cooling is form ed d u rin g the firs t nine days a fte r birth .[M am m als Res. Inst., P olish Acad. Sci., 17-230 Białow ieża]. INTRODUCTIONPine voles, Pitymys subterraneus (de Selys-Longchamps, 1835) are not capable after birth, like m any other mammal species, of m aintaining constant body tem perature. This does not mean, however, th at the body tem perature (TB) during the postnatal development period of young pine voles still living in the nest is subject to considerable and random fluctuations. Data on poikilothermy during the postnatal period do not in any way contradict the above statem ent, but each of these conclusions applies to a different situation. The opinion as to relatively constant body tem perature refers to individuals under natural conditions, in the nest, under m aternal (parental) care. The second opinion as to complete poikilothermy of newborn mammals is based on m easurem ents made under laboratory conditions, frequently on anim al's k ep t singly and outside the nest. Such research makes it possible to supplem ent our knowledge on the development of therm oregulation during the postnatal period, b u t does not state the tem perature of the growing rodents. Only measurements made on individuals in the nest can provide inform ation as to the value and range of variations in this index. Collection of data in the field is, however, limited with the present technical facilities available. Another solution is to use animals kept under sem i-natural conditions (enclosures) (Gębczyński, 1975). Meas urements made under laboratory conditions at different am bient tem peratures nevertheless give some guide as to the body tem perature of growing animals.The rate at which poikilothermy is formed can be evaluated by means of the capacity for maintaining constant body tem perature under conditions of physiological cold. In this way it is possible to estimate the anim al's resistance to cooling, which may be expressed by an index estimating the rate of changes in body tem perature in a unit of time. I[495]

Longitudinal Trajectories and Inter-parental Dynamics of Prairie Vole Biparental Care

“…Variation in parental behavior in this perinatal period has been predictive of pup bio-behavioral outcomes (Perkeybile et al, 2013). The perinatal period is also the period in which the most extensive parental care is shown, and it is a period in which, prior to fur growth, pups have little ability to thermoregulate (Gebczynski, 1981; Blake, 1992). The observed home cage was left undisturbed on a metal cage rack with overhead coverage from the rack above.…”