Toxic effect of chromium chloride on hematology of major carp (Labeo rohita)

Abstract

Human activities have caused contamination of heavy metals, which has become a significant threat to aquatic organisms. A study was conducted to investigate the impact of exposure to chromium chloride on the hematological parameters of Labeo rohita over 28 days. The study involved 240 randomly selected fish divided into four groups, with three groups exposed to varying sublethal concentrations of chromium (37, 22, and 11 mg/l), while the fourth group served as a control (0 mg/l). Results from the study showed that the experimental groups had significantly lower hematological parameters, such as mean cell hemoglobin, red blood cells, hematocrit, platelets, and hemoglobin, compared to the control group (P < 0.05). Conversely, mean cell volume and white blood cells increased, while white blood cell values declined on day 28. Additionally, an increase in macrophages and basophils indicated a protective response to chromium exposure. Furthermore, Labeo rohita exposed to sublethal doses of chromium chloride exhibited an increasing trend in mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) compared to the control group. The findings suggest that long-term exposure to chromium chloride has harmful effects on the hematological parameters of Labeo rohita, which is a significant carp species.