Evaluation of Hypericum Perforatum Effects on Hematological and Biochemical Factors of Rainbow Trout Under Thermal Stress
Abstract
Perforatum hypericum is one of the medicinal herbs known for its anti-depressant, anti-inflammatory and anti-cancer effects. Due to the resistance of fish against artificial antibiotic agents for controlling and treating infectious diseases, using medicinal plants is a new way to improve health and increase the productivity of fish production. In this study, the anti-stress effects of this plant extract have been investigated on rainbow trout. Rainbow trout fish with an average weight of 50 ± 5 grams were floated to different doses (0, 250, 500 and 750 ppm) of plant extract in two stages with 10-day interval and for 5 days. The investigated factors included the total count of white and red blood cells, differentiated leukocyte count (DLC) (lymphocyte and neutrophil percentages), Hematocrit, hemoglobin, mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC) and levels of Aspartate aminotransferase and Alanine aminotransferase. The results showed that 500 and 750ppm treatments showed a significant increase in both blood sampling times in count of red blood cells, hematocrit percentage and hemoglobin levels, compared to the control treatment at 5% level. In the count of total white blood cells in the first stage of blood sampling, at 500 ppm dose, and in the second stage, 750 ppm and 500 ppm doses showed significant increase with 95% probability. Also, the percentage of lymphocytes showed a significant increase in all doses (0, 250, 500 and 750 ppm) compared to control in both stages of blood sampling with 95% probability. Conversely, the mean neutrophil percent showed a significant decrease in all doses compared to control in both stages of blood sampling with 95% probability. The mean of MCV, MCH and MCHC in all doses had no significant changes in comparison with the control treatment. Also, the AST and ALT enzymes showed a significant increase at 750 ppm dose compared to control and other doses in both stages of blood sampling.
