Evaluation of oxidative stress in Tursiops truncatus: preliminary study.

The adaptation of marine mammals to aquatic life is a result of evolution. Being vertebrates, they frequently experience apnea, which can result in hypoxia and repeated cycles of ischemia/reperfusion when diving. Underwater vertebrates have developed a set of mechanisms that enable them to endure long periods of apnea (breathing) and enhance their ability to dive [1]. Recent studies have focused on marine mammals defenses against oxidizing by products and inflammation caused by ischemia, hypoxia, and reperfusion at the molecular level. The importance of highly adapted antioxidant systems in marine mammals for preventing oxidative stress has been underlined in numerous studies [2]. It is thought that there is a strong connection between oxidative stress and health and well- being. Assessing the health status of marine mammals is challenging because, unlike humans and domestic animals, the typical clinical signs of diseases in these species are difficult to recognize or interpret. Identifying the multiple aspects of the response to oxidative stress is crucial for marine mammal management and conservation. Our research is focused on investigating oxidative stress in Tursiops truncatus using the d-ROMs test, which determines the pro-oxidative state of measurement of hydroperoxides in serum, and the OXY-Adsorbent test, which measures the antioxidant barrier in serum samples [3]. d-ROMs and OXY ratio (x 100) was used to measure the degree of oxidative stress. At Zoomarine Italia in Torvaianica, RM, Italy, 11 clinically healthy bottlenose dolphins were examined and 11 samples of fasting blood serum were taken, with 6 representing males and 5 representing females between the ages of 9 and 42, and of 5 and 19, respectively. All dolphins kept in the facility were trained to participate voluntarily in veterinary and husbandry procedures to ensure regular routine diagnostic analysis. In particular, the animals were trained to perform voluntary venipuncture by presenting the fluke for blood collection without any physical restraint. The results showed that there was no correlation between d-ROMs and OXY values, while there was a weak and positive correlation between age and OXY values, and a weak and negative correlation between age and d-ROMs and between age and OSi, respectively. The results of this preliminary study are valuable in determining the health and well-being status of these marine mammals, which is essential for their management and conservation. To gain a better understanding of the pro-oxidant and antioxidant status of Tursiops truncatus and establish reference values, more studies are needed.