Circulating estradiol (E(2)), progesterone (Pro), testosterone, and corticosterone (B) levels were monitored in the green turtles Chelonia mydas during different nesting phases. Successful nesting includes emergence from sea, chamber and nest excavation, oviposition, burying the nest, and returning to sea. Unsuccessful nesting includes chamber and nest excavations but without oviposition. Blood samples were taken from the cervical sinus and collected within 5-min of capture to minimize stress. The samples were collected between 2000 and 0100 h during the peak season (May-October). High-performance liquid chromatography using a u.v. detection system coupled with tandem quadrupole mass spectrometry was used to measure B. Plasma B levels were significantly higher in successful and unsuccessful phases over emergence and excavation phases. However, B levels in successful versus unsuccessful or emergence versus excavation phases were not significantly different. Plasma steroid levels were measured by the Coat-A-Count RIA technique. Pro levels were significantly higher (P<0.005) in successful over unsuccessful turtles and also successful turtles over turtles in the other phases (P<0.01). The Pro levels immediately after nesting were found to be higher than that reported previously. Plasma testosterone values were higher in successful turtles but not significantly different from the turtles in other phases. Estrogen levels were undetected in all phases. Overall, the hormone values during different phases of nesting may play a major role in formulating the nesting behavior and physiology of the nesting activities in the green turtle.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1677/joe.1.06790 | DOI Listing |
Front Physiol
January 2025
Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa, Japan.
Mar Pollut Bull
January 2025
Australian Rivers Institute, Griffith University, Australia. Electronic address:
Differences in trophic level may result in differences in chemical exposure between species of sea turtles, as pollutants may bioaccumulate differentially in diet items. It is, therefore, crucial to understand species-specific differences in exposure and effect to accurately assess chemical risk to individual species. This study used blood collected from green and loggerhead turtles foraging in Moreton Bay, Queensland, Australia, to assess differences in chemical exposure and effect of two species foraging in the same area at different trophic levels.
View Article and Find Full Text PDFEClinicalMedicine
January 2025
Leicester Real World Evidence Unit, Diabetes Research Centre, Leicester General Hospital, University of Leicester, Leicester, LE5 4PW, UK.
Background: People with diabetes are at increased risk of hospitalisation, morbidity, and mortality following SARS-CoV-2 infection. Long-term outcomes for people with diabetes previously hospitalised with COVID-19 are, however, unknown. This study aimed to determine the longer-term physical and mental health effects of COVID-19 in people with and without diabetes.
View Article and Find Full Text PDFEcol Evol
January 2025
Ministry of Education Key Laboratory for Ecology of Tropical Islands, Key Laboratory of Tropical Animal and Plant Ecology of Hainan Province, College of Life Sciences Hainan Normal University Haikou China.
The green sea turtle () is the only sea turtle species that breeds in China, and the largest remaining nesting grounds for green sea turtles in Chinese waters is found on the Qilianyu atoll of the Xisha Islands. Nesting site selection is particularly important for egg survival, and understanding the microhabitat characteristics of green sea turtle nesting sites is crucial for delineating priority conservation areas for nesting grounds. In this study, we aimed to examine the role of several microhabitat ecological factors in the selection of nesting sites and the success of nesting.
View Article and Find Full Text PDFComp Biochem Physiol C Toxicol Pharmacol
January 2025
Graduate School of Science and Engineering, Iwate University, 4-3-5, Ueda, Morioka-city 020-8551, Japan.
As temperatures rise due to increasingly severe global warming, the effect of high temperatures on wildlife, including green sea turtles, is one of the issues that must be addressed to ensure the conservation of biodiversity. In the current study, we found that green sea turtle cell death due to apoptosis occurred at 37 °C, which suppressed cell proliferation. We also found that high temperature-induced heat stress led to the accumulation of DNA damage in green sea turtle cells.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!