List of Articles T4)

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  1 - Correlation of serum levels of T3 and T4 during the dry and postpartum periods with ovarian rebound in primiparous and multiparous cows
  افشین Davasaztabrizi خشایار Mehrani
  The thyroid gland is one of the major endocrine glands which plays an important role in vital balance of the body by secreting two hormones, T3 and T4. Because effects of these two hormones affect the activity of many body organs, in this survey the effects of these two More

  The thyroid gland is one of the major endocrine glands which plays an important role in vital balance of the body by secreting two hormones, T3 and T4. Because effects of these two hormones affect the activity of many body organs, in this survey the effects of these two hormones on the return of ovarian activity in Holstein cows were examined. For this purpose, 60 primiparous cows (having one pregnancy) and 60 multiparous (having two or more pregnancies) were considered for this survey. In both groups, the blood samples were taken 10 days before parturition and 10 to 20 days after parturition.  After centrifugation and serum separation, samples were stored at -20 o C. Afterwards in laboratory, T3 and T4 values were measured by using ELISA kit. The results indicate that the values of T3 and T4 in primiparous cows in the prenatal and postpartum period were more than multiparous cows (p<0.05). In both groups, values of T3 and T4 in postpartum period were reduced compared to prenatal period. T4 values in multiparous cows in the postpartum period showed significant correlation with the return time of ovarian activity. Finally, it can concluded that decreasing thyroid function and thyroid hormones deficiency, particularly T4, in the postpartum period can influence the prolongation of the onset of ovarian activity in multiparous cows but in primiparous cows due to the sufficient activity of the thyroid gland, the onset of ovarian activity should be sought in other factors.   Manuscript profile
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  2 - The effect of vitamin E and selenium on serum injection on serumic levels of T3 and T4 hormones in the Arabian horse
  بهرام Amouoghli-Tabrizi A. Hassanpour M. Khakpour Y. Mohamadpour-Tanha
       This study was conducted evaluate the effect of vitamin E and Selenium injection on serumic levels of thyroid hormones in the Arabian horse. Twelve Arabian stallions of approximately equal age were selected and based on their age (4 and 5 years old), More

       This study was conducted evaluate the effect of vitamin E and Selenium injection on serumic levels of thyroid hormones in the Arabian horse. Twelve Arabian stallions of approximately equal age were selected and based on their age (4 and 5 years old), allocated to tow groups each consisting of six animals. In each group, three of the six horses were injected by vitamins E and selenium at a dose rate of 1cc/30 kg intramuscularly every tow days and the other three animals which were chosen as the controls were similarly injected by normal saline solution. Two days alter each injection; blood samples of the horses in each group were collected using venoject from the jugular vein. After separating the blood serum by centrifuging, the levels of T3 and T4 were measured using the ELISA technique. Following the first injection, the serumic levels of thyroid hormones demonstrated a significant increase in comparison with the controls (p<0.05) while after the second injection, the serumic levels of T3 and T4 had decreased to normal values similar to the control groups. However, following the third injection the decreased in T3 and T4 levels was clearly evident and statistically significant (p<0.05). According to the results of the present study, the injection of vitamin E and selenium for more than twice leads to decrease in the seumic levels of T3 and T4 hormones of the horse and this is coupled with reduction of the basic body metabolism which is not beneficial for the animal. Manuscript profile