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Changes of thyroid hormones concentration in blood of sheep depending on age and reproductive status  [cached]
Josip Novoselec,Zvonco Antunovi?,Marcela ?peranda,Zvonimir Steiner
Italian Journal of Animal Science , 2010, DOI: 10.4081/ijas.2009.s3.208
Abstract: The influence of the reproductive status was tested in the blood serum of 30 sheep (10 pregnant sheep on the 15th day prior to lambing, 10 lactating sheep on the 20th day of the lactation and 10 non-pregnant sheep). The influence of age was determined in the blood serum of 20 sheep and 20 lambs. Analysis of the impact of age in sheep and lamb on the concentration of thyroid hormones showed that 30-day old lambs had significantly higher (P<0.01) concentration of T3 and T4 compared to the other age categories of sheep. At the same time, 100-day old lambs had significantly higher concentration of T4 if compared to the 1 and 3-year old sheep. Referring to the reproductive status, there was significantly lower (P<0.01) concentration of T3 determined in the blood of lactating sheep than of nonpregnant and pregnant sheep. These findings point out unsatisfactory energy supply in the older sheep, sheep during late pregnancy and sheep at the beginning of lactation.
Thyroid Hormones, T3 and T4, in the Brain  [PDF]
Martin L. Privalsky
Frontiers in Endocrinology , 2014, DOI: 10.3389/fendo.2014.00040
Abstract: Thyroid hormones (THs) are essential for fetal and post-natal nervous system development and also play an important role in the maintenance of adult brain function. Of the two major THs, T4 (3,5,3′,5′-tetraiodo-l-thyronine) is classically viewed as an pro-hormone that must be converted to T3 (3,5,3′-tri-iodo-l-thyronine) via tissue-level deiodinases for biological activity. THs primarily mediate their effects by binding to thyroid hormone receptor (TR) isoforms, predominantly TRα1 and TRβ1, which are expressed in different tissues and exhibit distinctive roles in endocrinology. Notably, the ability to respond to T4 and to T3 differs for the two TR isoforms, with TRα1 generally more responsive to T4 than TRβ1. TRα1 is also the most abundantly expressed TR isoform in the brain, encompassing 70–80% of all TR expression in this tissue. Conversion of T4 into T3 via deiodinase 2 in astrocytes has been classically viewed as critical for generating local T3 for neurons. However, deiodinase-deficient mice do not exhibit obvious defectives in brain development or function. Considering that TRα1 is well-established as the predominant isoform in brain, and that TRα1 responds to both T3 and T4, we suggest T4 may play a more active role in brain physiology than has been previously accepted.
Serum Proteins, Thyroid Hormones and Alkaline Phosphatase Concentrationsin Acute Experimental Trypanosoma congolense Infection in Yankasa Sheep Immunomodulated with Levamisole
M. Bisalla,K.A.N. Esievo,N.D.G. Ibrahim,I.A. Lawal
Journal of Animal and Veterinary Advances , 2012,
Abstract: Serum proteins, thyroid hormones and alkaline phosphatase concentrations were measured in Yankasa sheep experimentally infected with T. congolense. Parasitemia occurred in the T. congolense infected sheep immunomodulated with levamisole two days earlier than the infected group without immunodulation.Packed cell volume decreased significantly(p< 0.05) in the infected groups with and without immunomodulation when compared to the controls from the first week of infection up to the end of the experiment. Serum total protein, albumin, Thyroxine (T4) and Triiodothyronine (T3) decreased significantly (p< 0.05) in the infected sheep with and without immunodulation when compared to the controls. Serum Thyrotopin (TSH) and Alkaline Phosphate (AP) did not alter significantly (p>0.05) in the infected sheep with and without immunomodulation when compared to the controls throughout the period of the experiment. In general, levamisole administration did not appear to alter the infection when compared to the infected group without immunomodulation.
Thyroid hormones in the cerebrospinal fluid of the third ventricle of adult female sheep during different periods of reproductive activity
J. Skipor , T. Misztal , A. Szczepkowska
Polish Journal of Veterinary Sciences , 2010, DOI: 10.2478/v10181-010-0018-z
Abstract: Thyroid hormones (THs) are obligatory for transition from breeding season to anestrus in sheep. In this process, THs act during a very limited time of the year and primarily within the brain. In ewes chronically equipped for sampling cerebrospinal fluid (CSF) from the third ventricle, we have characterized the concentrations of total and free thyroxine (T4), triiodothyronine (T3), and total reverse T3 (rT3) in the CSF during breeding season, anestrus and during a critical period required for transition to anestrus (December-March). The total T4, T3, rT3 and free T3 average concentrations (± SEM) in CSF were 1.5 ± 0.07 ng/ml, 14.5 ± 1.2 pg/ml, 43 ± 7.4 pg/ml, and 0.6 ± 0.05 pg/ml, respectively, and all were significantly lower (p ± 0.001) than in blood plasma except free T4 (12.6 ± 1.1 pg/ml), which was similar to that in plasma. There was a seasonal trend (p ± 0.05) in the concentration of total T3 (highest in December) and free T4 (highest in November) in the CSF that does not follow that in blood plasma. During the period of transition to anestrus the CSF total T3/TT4 molar ratio and free T3/T4 ratio were significantly lower (p ± 0.05 and p ± 0.01, respectively) than in blood plasma, while the total rT3/T4 ratio was significantly higher (p ± 0.01) at the end of this period (March). Additionally, the CSF total rT3 concentrations were also significantly correlated with the CSF total T4 levels (r = 0.57; p ± 0.05). In conclusion, the CSF in sheep may serve as a considerable source of thyroid hormones for neuroendocrine events. The lack of significant changes in THs concentrations in the CSF during the period of transition to anestrus indicate that neither seasonal changes of THs circulating in the blood plasma nor THs circulating in the CSF actively drive the transition to anestrus.
Concentrations of thyroid hormones in various age categories of ruminants and swine
Paulíková Iveta,Seidel H.,Nagy O.,Tóthová Csilla
Acta Veterinaria , 2011, DOI: 10.2298/avb1106489p
Abstract: The goal of the study was to map the blood serum concentrations of thyroid hormones in various age categories in cattle, small ruminants, and swine. Blood serum concentrations of TSH, T4, and T3 were analysed in randomly selected healthy animals of various species and age. Age-dependent changes of thyroid hormones were studied in 7 clinically healthy calves during the first 6 months of life. The observation started at the age of one month (body weight 45 - 51 kg). A similar study was done in 9 sucking piglets since birth to 9 weeks of age (weaning at 35 days). Blood samples were taken every week. In calves, heifers, and dairy cows we recorded significant differences in T4 and T3 values with the highest levels in heifers (p<0.05). The hormones mean concentrations in sheep, goats, and swine corresponded to data reported by other researchers. Within age dependent studies, mean concentrations of TSH showed no significant changes, however, most of the samples showed concentrations below the detection limit of the assay. In the third month close to weaning we found significantly lower serum T4 concentrations (p<0.05), compared with the initial value. Similar, but however insignificant decrease was observed for T3 concentrations. In the piglets, both T4 and T3 concentrations showed a significant (p<0.001) decrease during the study with the highest mean concentrations of T3 and T4 in the youngest piglets. After weaning, both in calves and piglets concentrations of the hormones slightly increased.
The effects of zolpidem medicine on thyroid plasmic hormones of T3, T4 and TSH in male mature rats
Ebrahim Hosseini,Saeid Khatamsaz,Aida Goodarzi
Journal of Jahrom University of Medical Sciences , 2011,
Abstract: Introduction:Zolpidem drugs, as a GABA agonist, is one of the antidepressant and hypnotic drugs. Based on the results of the studies, excessive amounts of this drug could affect the amount of normal endocrine activity and its metabolic activities. Hence, there was an attempt in this study to measure the levels of hormonal axis hypothalamus – pituitary – thyroid hormone plasma in adult male rats.Material and Methods:In this research, 50 male mature rats with the weight of 200±10 grams were enrolled as the experiment, witness and control groups. The experimental group was divided into 3 subgroups and 150, 300 and 450 ml per kg of zolpidem was administered orally for 21 days. 0.2 ml distilled water was given to the witness group, but the control group did not receive anything. At the end of 21 days, blood sample was taken from the heart ventral areas and the density of the hormones of T3, T4 and TSH were measured using Eliza method and the commercial kits. The results were evaluated using independent T-test.Results:According to the results of this study, the density of T3 hormones in the experiment group did not show any meaningful differences with the control group, while the density of T4 and TSH hormones showed a meaningful decrease in the experiment and control groups (P<0.05).Conclusion:The results obtained from this study showed that zolpidem affects the hypothalamus, pituitary and also thyroid glands. According to the results of the research conducted, there is a possibility that zolpidem has this effect through an increase in prolactin exudation, leading to TRH exudation and decrease in TSH and thyroid hormones.
Effect of the breed and age on the thyroid hormones T3 and T4 concentrations in bovines under tropical conditions Efecto de la raza y la edad sobre las concentraciones de hormonas tiroideas T3 y T4 de bovinos en condiciones tropicales  [cached]
Campos Gaona Rómulo,Giraldo P Leonidas
Acta Agronómica , 2008,
Abstract: To study the effect of age and breed on blood concentration of thyroid hormones T3 and T4 under the dry tropic conditions, 158 animals from the groups Holstein, Lucerna, Hartón del Valle, Brahman and crossbred F1 Brahman x Brown Swiss were sampled. The animals were allocated in four age groups from newborns calves until eight month old. The average T3 concentration was of 2.25 mmolL-1 and the T4 was of 57.37 mmolL-1. The correlation between T3 and T4 was of 0.53. A statistical significant difference (p<0.001) was found for the effects of age breed and group, but not difference was found for the interaction between breed and age (p=0.286). The breeds with higher blood concentrations of T3 and T4 were Holstein and Lucerna. The lowest concentration was found among the crossbred group. The higher concentration of T3 and T4 of thyroid hormones was found in the newborn group. As the calves grow, the concentrations of T3 and T4 decrease progressively. This study found that under dry tropic conditions, in a thermo-neutral borderline zone (according to the THI index) the young bovines show clear differences in the concentration of the thyroid hormones.Key words: Adaptation; Bovine; Growth; Thyroids. Para estudiar el efecto en condiciones de trópico seco de la edad y del grupo racial sobre las concentraciones séricas de las hormonas tiroideas T3 y T4, se muestrearon 158 animales de los grupos raciales Holstein, Lucerna, Hartón del Valle, Cebú Brahman y mestizo F1 (Cebú Brahman x Pardo Suizo), distribuidos en cuatro grupos de edad desde el nacimiento hasta el destete (8 meses). La concentración media de T3 fue 2.25 mmol/L y la de T4, 57.37 mmol/L. La correlación entre T3 y T4 fue de 0.53. Se encontró diferencia estadísticamente significativa para el efecto grupo racial, grupo de edad (P<0.001) pero no para la interacción grupo racial x edad (p=0.286). Los grupos raciales con concentraciones más elevadas fueron Holstein y Lucerna; la concentración más baja se presentó en los bovinos mestizos. La mayor concentración de hormonas tiroideas según la edad ocurrió en recién nacidos, luego descendió progresiva y linealmente. El trabajo encontró que en condiciones de trópico seco, en zona límite de termoneutralidad según el índice ITH, los bovinos jóvenes presentanron diferencias marcadas en las concentraciones de hormonas tiroideas.Palabras claves: Adaptación; Bovinos; Crecimiento; Tiroides.
Physiological Response of Two Age Groups of Omani Sheep to Short Road Transportation in Relation to Circulating Levels of Gonasotropins, Cortisol, Thyroid
Hormones,Sex Steroids,Plasma ChemistryA. Al-Kindi,I. T. Kadim A.,I.Y. Mahmoud,O. Mahgoub,J. Plude,M. Al-Maani
Journal of Animal and Veterinary Advances , 2012,
Abstract: Two age groups of Omani sheep were subjected to a short period transportation under two sets of stress conditions. Blood samples were collected by jugular veinpuncture just before slaughtering and the degree of stress was related to hormone levels and blood chemistry. Chemiluminescence’s immunoassay technique was used to determine levels of cortisol,, gondadotropin (FSH, LH), Testosterone (T), Thyroid Stimulating Hormone (TSH) and Thyroid Hormones (T3, T4). Adrenaline, noradrenaline, and dopamine levels were determined by HPLC with electrochemical detection. In addition, plasma values of cholesterol, total protein, blood urea nitrogen (BUN3), lactate, CO Mg , PO , Ca and uric acid were also analyzed. A total of ++ ++ ++ 24 sheep were used, 12 at age of 6 months and 12 at 12 months. Each age group was randomly divided equally into control and experimental. The control sheep from each age group were transported using open truck (3X2 m) three days before they were slaughtered. The sheep were loaded at 7:00am on a 2 h journey with heavy traffic under air temperature, which varied between 30-31?C. The end of the journey, each age group was kept weparat3ly in a lairage of a commerical slaughterhouse, with food and water ad libitum. The xperimental group was subjected to the same transportation condition and with approximately the same temperate range except they were transported the same day they were slaughtered. The sheep in both age groups, which were transported the same day and then slaughtered at the end of the journey (experimental) had significantly higher cortisol value (p<0.001) than the control sheep of both ages. There was no significant difference in the catecholamine values between the experimental and control of both age groups but adrenaline and dopamine levels in the 12month sheep were significantly higher in both categories (p<0.001) than the 6month sheep. There was no clear trend in the hormone profiles and the values generally exhibited mixed results. For example FSH, TSH and T3 values wer3e significantly (p<0.05) higher in the 6-month control over the experimental, but in the 12month sheep the results were the opposite. In the blood parameters, there was also unclear trend in values. In the 6 month control, at least all the parameters were significantly lower (p<0.05) than in the experimental but the results were opposite in the 12 month sheep. Th3ere is some indication that the Omani sheep which transported on the same day demonstrated a degree of physiological stress which is based on higher values of cortisol. This probably is not caused by transportation alone but also on loading and unloading as well.
Epidemiological Study of T4, T3 and TSH Mean Concentrations in Four Iranian Populations
M Fathzadeh,Y Seyedna,H Khazali,M Sheidai
Iranian Journal of Public Health , 2005,
Abstract: T4 and T3, two major hormones of thyroid gland, are responsible for regulation of “basal metabolism” in the body. Thyroid function is regulated primarily by variation in the pituitary TSH. In this study, about four hundred individuals were considered from four Iranian populations. They were selected randomly in their cities; Shiraz, Mashhad, Rasht, and Ilam. Essential family information was asked to achieve native belonging of each person to related population. Blood specimens were collected, by separating serums, freezed serums were transferred immediately to Tehran for hormone assay. Assay of T4 and T3 concentrations was carried out by “RIA-magnetic” kits and of TSH by “IRMA-magnetic” kits. Analysis of variance has been taken into account among days of sampling in each city to calculate mean concentrations for T4, T3 and TSH. Analysis of association between age and hormones concentrations in each population was done by the regression and the correlation tests. Significant differences were detected at T4 mean concentration in each of these populations (P=0.0001). Differences for T3 mean concentration were observed only between Shiraz and Mashhad (P=0.021); and Shiraz and Rasht (P=0.003). By increasing age of individuals, there were also a negative correlation at mean concentrations of T4 and T3 in Ilam (P=0.022), and Mashhad (P=0.016) respectively. According to these data, and specificity of environmental and genetic factors to each popualtions, specific “normal reference” of T4 and T3 homones should be considred for each of these populations. Correlation study of mean concentrations of these hormones and genetic variations of some critical genes such as thyroid peroxidase (TPO) and iodothyronine deiodinase can open new window of epidimiology among Iranian popualltions.
Efecto de la raza y la edad sobre las concentraciones de hormonas tiroideas T3 y T4 de bovinos en condiciones tropicales
Campos Gaona,Rómulo; Giraldo P,Leonidas;
Acta Agronómica , 2008,
Abstract: to study the effect of age and breed on blood concentration of thyroid hormones t3 and t4 under the dry tropic conditions, 158 animals from the groups holstein, lucerna, hartón del valle, brahman and crossbred f1 brahman x brown swiss were sampled. the animals were allocated in four age groups from newborns calves until eight month old. the average t3 concentration was of 2.25 mmoll-1 and the t4 was of 57.37 mmoll-1. the correlation between t3 and t4 was of 0.53. a statistical significant difference (p<0.001) was found for the effects of age breed and group, but not difference was found for the interaction between breed and age (p=0.286). the breeds with higher blood concentrations of t3 and t4 were holstein and lucerna. the lowest concentration was found among the crossbred group. the higher concentration of t3 and t4 of thyroid hormones was found in the newborn group. as the calves grow, the concentrations of t3 and t4 decrease progressively. this study found that under dry tropic conditions, in a thermo-neutral borderline zone (according to the thi index) the young bovines show clear differences in the concentration of the thyroid hormones
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