Ograniczanie wyników

Czasopisma help
Autorzy help
Lata help
Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 58

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 3 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych:  kortyzol
help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 3 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
The aim of this study was to determine physiological levels of stress hormones (e.g. cortisol and testosterone) in the blood of polar fox females characterized by a specific genotype and karyotype and also the type of behavior. In 2010, an estimation of the type of behavior of all females from a pack based on the type of behavioral response (empathic test, alimentary test, acoustic test) was provided. In the blood of 136 females randomly selected from the fundamental pack, physiological levels of stress hormones (e.g. cortisol and testosterone) were determined. Additionally, the analysis of polymorphism of karyotypes of 72 females in this group was conducted. Heritability and repeatability coefficients in the base levels of cortisol and testosterone in the blood serum was evaluated. The average basal level of cortisol in the blood serum of polar fox females was 46.04 ± 25.86 nmol/l, and testosterone 0.45 ± 0.22 nmol/l. The heritability coefficient of the basal cortisol level stated 0.30 ± 0.11 and testosterone 0.24 ± 0.13; the repeatability coefficient of the basal levels of cortisol was 0.42 and 0.37 of testosterone. The multivariate analysis of variance revealed non-significant differences between the studied groups of animals. Some tendencies were noted explaining the differentiation in hormone levels within particular effects (participation of genes of Finnish variety, karyotype and type of behavior: empathic test, alimentary test and acoustic test). The highest basal levels of cortisol (51.98 nmol/l) and testosterone (0.51 nmol/l) were found in the group of foxes of national breeding. The highest value of cortisol was obtained in the female group of 48 chromosomes (55.20 nmol/l) and lowest in a group of foxes with karyotype 2n = 50 (49.06 nmol/l). Studies have shown the highest physiological level of testosterone in the blood of gentle individuals. It was also noted that foxes with a high concentration of this hormone were simultaneously characterized by a low cortisol level.
Blood sampling, especially in young pigs, is a stressogenic procedure and brings about a release of various hormones to the peripheral blood. According to many authors blood collection, performed by means of a previously inserted catheter, has an advantage in comparison to traditional methods based on direct venapuncture. The purpose of the experiment was to carry out comparative investigations in respect to the level of adrenaline, noradrenaline and cortisol (stress hormones) during blood sampling from porkers. Two methods were used: a) a traditional one based on a direct venapuncture of the jugular anterior vein, and b) by means of a previously inserted catheter through the brachiocephalic vein to the jugular anterior vein. Blood samples were collected at 20, 40, 80, 110, 200 and 300 seconds counting the time from catching and immobilization of an animal to the end of blood sampling. The results did not reveal any significant differences in the level of the hormones in the blood samplings taken by both methods. The results proved that the stress aroused by the blood sampling was caused by catching and immobilization of animals and not by the method of blood aspiration. The traditional method of blood sampling (direct venapuncture) can be used in young animals housed in groups if the whole procedure does not last more than 22 sec., ie before the stress hormones are released in to the peripheral blood.
Исследования провели на ферме промышленного откорма свиней на 108 поросятах, у которых применили следующие виды стресса: 3-часовое отделение от матерей, 3-часовое охлаждение среды до 16°С и образование новых технологических групп по окончании периода сосания. Инcенcивность состояний стресса оценивали на основе изменений уровня адми данными контрольных животных. В свете гормональных измерений наиболее сильным технологическим стрессом было охлаждениэ окружающей среды, вызывая статистически существенные изменена в уровне всех исследуемых гормонов. Отъем, транспорт и образование новых технологических групп животных вызывали многократный рост содержания кортизола, 3-часовая же сепарация поросят от свиноматок не вызывали существенных езменений в уровне катехоламинов и кортикоидов.
The aim of this study was a comparative analysis of five minute episodes of mechanical colonal descending distension (CD) of different degrees, which were provoked by the insertion of a balloon filled with 150 and/or 200 ml of water (CD150 and/or CD200), and plasma cortisol concentration changes as a consequences of the hypothalamo-pituitary-cortico-adrenal axis (HPA) stimulation and nociceptive/stressoric effects. Furthermore, noting the comparative influence of premedication by metabotropic glutamate receptor antagonists via L-isomer and DL-AP3 racemate i.c.v. one min infusion in three different doses (0.2, 0.4 or 0.8 and 4.0, 8.0 or 12.0 mg in toto, respectively) on the plasma cortisol concentration changes, during 120 min of experimentation. The experiment was carried out in four series using 12 female sheep, Polish Merinos, in the anoestrus period (May–June). In the first series (six animals as a control group) the animals had a 200 μl 0.9% NaCl i.c.v. infusion. In the second series they (six animals) had a five min episode of CD by insertion of a balloon filled with 150 and/ or 200 ml of water (CD150 or CD200). In the third series of the experiment six animals had an i.c.v. DL-AP3 or L-AP3 infusion in three different doses (4.0, 8.0 or 12.0 and 0.2, 0.4 or 0.8 mg in toto, respectively), and in the fourth series, ten minutes before CD200, every week. Colon descending distension episodes lasting five minutes provoke a very repetitive, statistically significant increase of plasma cortisol concentration, a critical indicator of the stressoric effect as a consequence of HPA axis stimulation. Undoubtedly DL-AP3 racemate and L-isomer AP3, as metabotropic nonspecific glutamate receptor type-1 antagonists, attenuated this elevation of cortisol, and can be an alternative drug in colonal pain caused by wall distention in sheep.
Present studies yielded the following conclusions: the transport caused statistically significant rise of ACTH and cortisol concentrations in the blood of carp reared in the thermal-effluent channel. Usage of glass tanks for accommodating the fish caused prolongation of the stress reaction and maintenance of high ACTH and cortisol levels beyond the 7-day period monitored in the present experiment.
The present study revealed that intensive culture of two-year-old carp, using a high-fat diet (group 1) or a high-carbohydrate diet (group 2), causing a statistically significant rise of cortisol level, resulted in statistically significant rise in potassium ion concentrations as well as a statistically significant drop in chloride ion concentrations (group 1 only).
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 3 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.