Elevated plasma concentrations of haptoglobin in European brown bears during hibernation.

Haptoglobin (Hp), a hemoglobin-binding protein, is known as an acute phase protein and increases during the acute phase of inflammation in most mammals. We reported previously in brown bears that the mean Hp concentrations were higher in blood samples obtained in winter than those in spring. To examine a possible relation of the seasonal variations of Hp to hibernation, in the present study, we measured the plasma concentrations of Hp as well as some other acute phase proteins (alpha(2)-macroglobulin, alpha(1)-antitrypsin, C-reactive protein) in 6 European brown bears (Ursus arctos), from which blood samples were obtained at 5-6 different months of year including February, the time of hibernation.

Tannins--a dietary problem for hand-reared grey partridge Perdix perdix after release?

A 4-week feeding trial on 22 grey partridges Perdix perdix was conducted in this study. Seven birds were fed commercial poultry food, seven natural food and eight commercial poultry food containing 6% of quebracho-tannin. Our results suggest that 6% dietary tannin, when added to a commercial food with high protein content, effects the grey partridge only slightly.

Impact of hand-rearing on morphology and physiology of the capercaillie (Tetrao urogallus).

Morphological and physiological disparities between 20 captive and 11 wild capercaillies were determined. Birds, their pectoral and leg muscles, hearts, livers and gizzards were weighed. The length of small intestines and caeca were measured.

Cardiovascular and thermoregulatory responses to vasotocin and angiotensin II in the pigeon.

The cardiovascular and thermoregulatory effects of intrahypothalamically (preoptic/anterior hypothalamus) and intravenously injected arginine vasotocin (AVT) and [Val5]angiotensin II (ANG II) were measured at 2 degrees C in the pigeon (Columba livia). In addition, the effects of intrahypothalamic and intravenous injections of AVT on respiratory rates were measured at 10-15 degrees C. Intrahypothalamic and intravenous AVT (500 ng and 20 micrograms/kg, respectively) reduced shivering and body temperature but had no effects on blood pressure, heart rate or respiratory rate.

Submaximal exercise in the cold: does cooling potentiate the development of muscle injuries in the rat?

To test the effect of low ambient temperature on muscular strain and possible development of muscle injuries, male Sprague-Dawley rats (n = 35) were exercised at a speed of 15 m min-1 on a treadmill at a 6 degrees inclination for 1.5 h in a warm (22 degrees C) or a cold (-10 degrees C) environment. Blood and tissue samples were collected 0 and 48 h postexercise.

Energy cost and thermoregulation of unrestrained rats during exercise in the cold.

The effect of cold ambient temperature on the energy cost and thermoregulation during exercise was studied in 18 male Sprague-Dawley rats accustomed to running for 2 weeks. For measuring T(b) and ensuring an unrestrained exercise performance, the rats were implanted with intraperitoneal telemetric radio transmitters. The rats ran at three submaximal exercise intensities (10, 15 and 20 m.

Noradrenaline-induced hypothermia is suppressed in the vagotomized cold-exposed pigeon.

Vagotomized (VX) pigeons studied 2 days after surgery exhibited a significant decrease in cloacal temperature (Tb) and respiratory rate (Rf), and an increase in heart rate (Hf) and metabolic rate (M) at the thermoneutral zone, when compared with sham-operated (SVX) pigeons. The effect of intravenous noradrenaline (NA) on Tb, Rf, Hf and M was examined in SVX and VX-pigeons at 15 degrees C. Following NA administration, the Tb and Rf in the SVX-birds dropped from the preinjection level, but in VX-pigeons, they were not significantly altered.

Seasonal patterns in the physiology of the European brown bear (Ursus arctos arctos) in Finland.

The physiological indicators such as body temperature, blood chemistry and hematology of seven European brown bears (Ursus arctos arctos) were used in the present study. They were kept in either the Zoological Garden of University of Oulu (65 degrees N, 25 degrees 24'E) or the Ranua Zoological Garden approx. 150 km NE of Oulu.

Metabolism, thermogenesis and daily rhythm of body temperature in the wood lemming, Myopus schisticolor.

Wood lemmings (Myopus schisticolor) were captured during their autumnal migration in September and October. The animals were maintained at 12 degrees C and under 12L:12D photoperiod. Basal metabolic rate and thermogenic capacity of the wood lemming were studied.

The abnormal conduct of capercaillies Tetrao urogallus.

The frequency, behavior, and testosterone levels of deviant capercaillies were studied in southern Finland. Roughly 1% of the population was estimated to behave abnormally. Deviant males display and show threatening behavior toward not only humans, but also attacked stuffed capercaillie males and without hesitation copulated with a stuffed female.

Nocturnal hypothermia in fasting Japanese quail: the effect of ambient temperature.

Japanese quail were equipped with intraperitoneal transmitters for telemetric measurement of body temperature (Tb) and activity. Food deprivation at + 24 degrees C for four days induced a well-defined nocturnal hypothermic response. The normal day-night difference (about 1 degrees C) in Tb increased 1 degrees C per day, reaching 5 degrees C on the fourth night of fast.

Central control of body temperature. A review.

The control of body temperature takes place in the central nervous system at different levels, from the spinal cord to the upper parts of the brain. Experimental studies have shown that heat-producing muscular shivering is stimulated only when the spinal cord becomes cooler. The regulation of other components participating in the control of thermoregulation proceeds in hierarchical order so that the coordination takes place ultimately in the hypothalamus, mainly in the preoptic region, and at the same time temperature regulation is coupled with other autonomic functions such as control of food intake, osmoregulation, and hormone secretion.

Suppression of sympathetic nervous system by short photoperiod and melatonin in the Syrian hamster.

Exposure to short photoperiod or melatonin treatment brings about gonadal regression in Syrian hamsters. The possible influence of these treatments on the sympathetic nervous system (SNS) in these animals was investigated. Male Syrian hamsters were exposed to either long or short photoperiod or subjected to administration of melatonin or its vehicle solution.

Effects of short photoperiod and melatonin treatment on thermogenesis in the Syrian hamster.

This study investigated whether short photoperiod or melatonin-treatment could alter the thermogenic capacity of Syrian hamsters. Exposure of hamsters to short photoperiod and to exogenous melatonin treatment induced gonadal regression and hypertrophy of brown adipose tissue (BAT). Short photoperiod and melatonin-induced BAT hypertrophy was not accompanied by any change in noradrenaline (NA) turnover in this tissue.

Seasonal changes in some plasma hormones in pigeons: diurnal variation under natural photoperiods with constant or seasonally changing ambient temperature.

The diurnal variations of several plasma hormones and free fatty acids (FFA) were studied during periods in summer and winter for pigeons reared either outdoors or indoors. The latter were subjected to constant temperature and naturally varying photoperiods. A significant seasonal variation in the mean daily levels of triiodothyronine (T3), thyroxine (T4), corticosterone (B), lutropin (LH) and FFA was seen in the outdoor birds and in the T4 and B levels of indoor birds.

Seasonal changes in some plasma hormones in pigeons from different environments.

Seasonal variation in the plasma concentration of lutropin (LH), follitropin (FSH), prolactin (PRL), thyroxine (T4), triiodothyronine (T3) and corticosterone (B) were measured in the pigeon by RIA methods. Pigeons were maintained indoors under constant ambient temperature (Ta) and simulated natural daylight (LD), 12:12 L:D regimens or outdoors exposed to seasonal variations in temperature and photoperiod at Oulu, Finland. Only slight changes of gonadotropins (LH, FSH) were observed throughout the year, without any clear photosensitive or photorefractory period.

The influence of ambient temperature on metabolism and body temperature of newborn and growing reindeer calves (Rangifer tarandus tarandus L.).

Thermoregulatory capacities of 51 reindeer calves (Rangifer tarandus tarandus L.) aged 1-35 days were studied at -26.5 to +35.

The effect of pinealectomy on plasma levels of thyroid hormones in pigeons reared under different photoperiods.

The effects of pinealectomy on plasma T3, T4 and free T4 concentrations were studied for about 10 weeks in pigeons maintained either under a constant short photophase or in a regime where a long photophase was replaced by a short one during the experiments. The results indicate that, regardless of the photoperiod, no clear functional relationship can be found between the avian pineal gland and thyroid function, although a transitory increase in T4 levels was seen in both pinealectomized and sham-operated birds shortly after the operations.

Hyperthermia after intrahypothalamic injections of thyrotropin releasing hormone (TRH) in the pigeon.

Thermoregulatory responses to intrahypothalamic injections of thyrotropin releasing hormone (TRH) were recorded from unanesthetized pigeons exposed to 6 degrees C, 20 degrees C and 32 degrees C. Our results suggest that TRH is a non-specific excitatory neuromodulator or neurotransmitter for heat production in the pigeon.

Annual variation in the concentrations of circulating hormones in capercaillie (Tetrao urogallus).

Seasonal variation in the levels of immunoreactive lutropin (LH), follitropin (FSH), prolactin (PRL), corticosterone (B), thyroxine (T4), and triiodothyronine (T3) was measured in the plasma of male and female capercaillies (Tetrao urogallus, Galliformes) in captivity (latitude N 67 degrees). In male capercaillies there was an increase in the concentrations of LH and FSH beginning in March and reaching their maxima in May, which correlated with the nesting period. The concentration of plasma PRL increased from the end of April and reached its highest level simultaneously with the rapid fall of plasma LH and FSH concentrations.

Propranolol induced changes in plasma catecholamine, corticosterone, T4, T3 and prolactin levels in the pigeon.

Concentrations of plasma noradrenaline, adrenaline, corticosterone, thyroxine (T4), triiodothyronine (T3) and prolactin were measured in pigeons at 22 degrees C after intravenous injection of propranolol (1 mg/kg). An increase in catecholamines occurred in 5 or 15 min. T4, T3 and prolactin increased within 30 and 60 min after injection, however, after correction for the differences in plasma protein content, only the concentration of prolactin was significantly above the control values.