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  1. Levesque DL, Lobban KD, Lovegrove BG
    PMID: 25155185 DOI: 10.1007/s00360-014-0858-4
    Tenrecs (Order Afrosoricida) exhibit some of the lowest body temperatures (T b) of any eutherian mammal. They also have a high level of variability in both active and resting T bs and, at least in cool temperatures in captivity, frequently employ both short- and long-term torpor. The use of heterothermy by captive animals is, however, generally reduced during gestation and lactation. We present data long-term T b recordings collected from free-ranging S. setosus over the course of two reproductive seasons. In general, reproductive females had slightly higher (~32 °C) and less variable T b, whereas non-reproductive females and males showed both a higher propensity for torpor as well as lower (~30.5 °C) and more variable rest-phase T bs. Torpor expression defined using traditional means (using a threshold or cut-off T b) was much lower than predicted based on the high degree of heterothermy in captive tenrecs. However, torpor defined in this manner is likely to be underestimated in habitats where ambient temperature is close to T b. Our results caution against inferring metabolic states from T b alone and lend support to the recent call to define torpor in free-ranging animals based on mechanistic and not descriptive variables. In addition, lower variability in T b observed during gestation and lactation confirms that homeothermy is essential for reproduction in this species and probably for basoendothermic mammals in general. The relatively low costs of maintaining homeothermy in a sub-tropical environment might help shed light on how homeothermy could have evolved incrementally from an ancestral heterothermic condition.
    Matched MeSH terms: Body Temperature/physiology*
  2. Lee JY, Wakabayashi H, Wijayanto T, Hashiguchi N, Saat M, Tochihara Y
    Eur J Appl Physiol, 2011 Dec;111(12):2895-905.
    PMID: 21437607 DOI: 10.1007/s00421-011-1912-5
    For the coherent understanding of heat acclimatization in tropical natives, we compared ethnic differences between tropical and temperate natives during resting, passive and active heating conditions. Experimental protocols included: (1) a resting condition (an air temperature of 28°C with 50% RH), (2) a passive heating condition (28°C with 50% RH; leg immersion in a hot tub at a water temperature of 42°C), and (3) an active heating condition (32°C with 70% RH; a bicycle exercise). Morphologically and physically matched tropical natives (ten Malaysian males, MY) and temperate natives (ten Japanese males, JP) participated in all three trials. The results saw that: tropical natives had a higher resting rectal temperature and lower hand and foot temperatures at rest, smaller rise of rectal temperature and greater temperature rise in bodily extremities, and a lower sensation of thirst during passive and active heating than the matched temperate natives. It is suggested that tropical natives' homeostasis during heating is effectively controlled with the improved stability in internal body temperature and the increased capability of vascular circulation in extremities, with a lower thirst sensation. The enhanced stability of internal body temperature and the extended thermoregulatory capability of vascular circulation in the extremities of tropical natives can be interpreted as an interactive change to accomplish a thermal dynamic equilibrium in hot environments. These heat adaptive traits were explained by Wilder's law of initial value and Werner's process and controller adaptation model.
    Matched MeSH terms: Body Temperature/physiology*
  3. Soleimani AF, Zulkifli I, Omar AR, Raha AR
    Poult Sci, 2011 Jul;90(7):1435-40.
    PMID: 21673158 DOI: 10.3382/ps.2011-01381
    Domestic animals have been modified by selecting individuals exhibiting desirable traits and culling the others. To investigate the alterations introduced by domestication and selective breeding in heat stress response, 2 experiments were conducted using Red Jungle Fowl (RJF), village fowl (VF), and commercial broilers (CB). In experiment 1, RJF, VF, and CB of a common chronological age (30 d old) were exposed to 36 ± 1°C for 3 h. In experiment 2, RJF, VF, and CB of common BW (930 ± 15 g) were subjected to similar procedures as in experiment 1. Heat treatment significantly increased body temperature, heterophil:lymphocyte ratio, and plasma corticosterone concentration in CB but not in VF and RJF. In both experiments and irrespective of stage of heat treatment, RJF showed lower heterophil:lymphocyte ratio, higher plasma corticosterone concentration, and higher heat shock protein 70 expression than VF and CB. It can be concluded that selective breeding for phenotypic traits in the domestication process has resulted in alterations in the physiology of CB and concomitantly the ability to withstand high ambient temperature compared with RJF and VF. In other words, domestication and selective breeding are leading to individuals that are more susceptible to stress rather than resistant. It is also apparent that genetic differences in body size and age per se may not determine breed or strain variations in response to heat stress.
    Matched MeSH terms: Body Temperature/physiology
  4. Naicker AS, Roohi SA, Lee CS, Chan WH, Tay LS, Din XJ, et al.
    Med J Malaysia, 2006 Feb;61 Suppl A:10-3.
    PMID: 17042221
    Poor glycaemic control and the duration of diabetes mellitus are known to accelerate development and progression of neuropathy. Diabetic co-morbidities: hypertension and hyperlipidaemia, have been postulated to associate with development of neuropathy. A diabetic foot with low temperature and frequent exposure to low temperature environment has recently been hypothesized to be at higher risk to develop early neuropathy. This cross-sectional study is undertaken to identify risk factors for diabetic neuropathy and the association between foot temperature and development of diabetic neuropathy by using simple clinical examination in the outpatient setting. From April 18, to April 30, 2005, universal sampling method was used to select 134 diabetic patients (type 1 or type 2 for >1 year) with peripheral neuropathy. Excluded are those with chronic alcoholism, drug-induced neuropathy, dietary history of vitamin B deficiency and family history of porphyria and hereditary sensorimotor neuropathy. The patient's duration of diabetes, glycaemic control status and the presence of co-morbids: hypertension and hyperlipidemia, were recorded. The temperature of the foot was measured by using thermo buddy. Of 134 patients representing Malaysian ethnic distribution with an equal number of males and females, 20.1% were in the age group of 61 to 65 years and, 85.1% and 67.9% belonged to lower socioeconomic and educational groups respectively. Associations between diabetic neuropathy and glycaemic control (p = 0.018) and duration of diabetes (p < 0.05) were significant. However, hypertension, hyperlipidaemia and low foot temperature were not significantly associated with development of diabetic neuropathy. Poor glycaemic control is significantly associated with diabetic neuropathy. Foot temperature alteration is merely an effect of autonomic neuropathy with a cold foot is attributed to co-existing peripheral arterial disease.

    Study site: Pusat Perubatan Primer Bandar Tasik Selatan, Kuala Lumpur, Malaysia
    Matched MeSH terms: Body Temperature/physiology*
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