Abstract
Blood samples of 1-year-old male jundiá ( Rhamdia quelen, Quoy and Gaimard) were collected to determine the effects of both acute and chronic stress in hematological parameters. The acute stress was induced by draining the water tank and transferring fish to another tank; chronic stress was induced by maintaining the fish in crowded concrete tanks. The cortisol level of male fish, 1 h after transferring from one tank to another, reached 176.78±21.3 ng/ml in contrast to 28.89±5.19 ng/ml found before transferring. Chronic stress, induced by 10 days of crowding in concrete tank, maintained the cortisol levels in approximately 64.48±18.9 ng/ml. The haematological parameters evaluated (RBC, WBC, and haemoglobin) were not significantly affected by acute stressor. However, after 10 days of chronic stimulation, all these values changed, with a significant decrease in lymphocytes, eosinophils, monocytes and special granulocyte cells, as well in RBC and hematocrit. The main result found in this work was the reduction of approximately 80% in the lymphocyte counts. This reduction could lead to a decreased ability to mount an immune response to environmental pathogen and could be an indication that the correct management of brood and culture stocks is important to prevent stress and the deleterious effects of increased cortisol levels to fish health.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.