Plasma T3 and T4 Hormone Levels as Reference Values in Rehabilitated Common Buzzard (Buteo buteo), Long-Legged Buzzard (Buteo rufinus) and Golden Eagle (Aquila chrysaetos)

Abstract

Applying appropriate criteria for raptors at rehabilitation stages including release and post release determines how healthy the animal can survive in its natural habitat for any length of time. In determining release criteria, clinical examinations of animals as well as clinical data should be evaluated. In this study, plasma T3 and T4 levels of 16 Common Buzzard (Buteo buteo), 7 Long-legged Buzzard (Buteo rufinus) and 7 Golden Eagles (Aquila chrysaetos) were determined at Kafkas University/ Kafkas Wildlife Conservation, Rescue, Rehabilitation Practice and Research Center between 2016-2018. All raptors were kept at the rehabilitation center for 1-3 months in bird care rooms and flight tunnels specially arranged for each species. Rehabilitated birds blood were collected before released to wild. Plasma T3 and T4 hormone levels were analysed and determined in raptors that considered suitable for release. Although small differences were detected between T3 and T4 values as a result of the analysis, no statistical difference was found. These small differences in values may be due to the metabolic responses and environmental conditions of each raptor. As a result, these plasma thyroid hormone levels in rehabilitated raptors can be accepted as reference values.