Relationship between ghrelin hormone and some thyroid hormones during seasons in Turkish Awassi Rams in Iraq

Abstract

The present study was designed to investigate the role of seasonality changes on some physiological aspect of Ghrelin and some parameters related to thyroid function in adult rams. Ten adult Turkish Awassi rams (1.2-1.3 years in age) and bodies weights ranged (45-58kg) were used in this study, which lasted from the beginning of January 2016 to the end of October 2016. Body weights of each individual ram were taken. Fasting blood samples were collected every ten days along the experiment (considered as fasting state), and then blood samples was collected one hour after feeding for the same ten adult rams (considered feeding state). The blood was collected from the jugular vein, and divided into two parts, which was centrifuged at (3000 rpm for 20 minutes) to separate the serum which was required for estimation (Ghrelin, TSH, T3 and T4). The environmental temperature was measured by using special thermometer every day along experimental period. The results of this study revealed a significant increase (p≤0.01) in ghrelin hormone concentrations in Turkish awassi rams serum at fasting state as compared to feeding during spring months. Serum TSH, T3 and T4 levels showed a significant increase at the feeding state as compared to fasting and represent the lowest level during winter months of the year. In conclusion, there is a negative relationship between the ghrelin hormone and thyroid hormones under the effect of seasonality in the Turkish awassi rams. In conclusion, the results of this study was the first in Iraq, give an important document that ghrelin hormone correlates negatively with thyroid hormones during different seasons