Evolution of the Thyroid Hormones (T3, T4) and Progesterone Levels in Ewes and Gimmers after the Insertion of Melatonin Implants
Keywords:
ewe, progesteron, thyroid hormonesAbstract
Investigations were carried on in a private farm from Cenad, Timis County, on 14-15 months of age gimmers from the indigenous breeds Transylvanian Merino (9) and Turcana (6). The gimmers were inserted in 14 May 2009 with Melatonin implants of 18 mg. Blood samples were collected immediately after the insertion of the implants and after 15 and 30 days. Hormones analysis triiodothyronine (T3), triiodothyronine (T4) and progesterone level from the blood samples were assayed using ELISA method. Data shown a decrease of the progesterone levels after 30 days from the insertion of the implants, but the difference of 4.69 mg/ml is not statistically significant (p>0.05), and the triiodothyronine (T3, T4) levels have registered small and insignificant variations (p>0.05). Results may suggest that melatonin implants do not influence significant (p>0.05) the thyroid hormones (T3, T4) and the progesterone levels.
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