Seasonal Variations in Hematological and Biochemical Parameters of Labeo rohita from River and Pond Habitats

This study aimed to evaluate the role of hematological and biochemical parameters as indicators of seasonal stress in Labeo rohita from pond and river habitat. Biochemical and muscle parameters of Labeo rohita collected from two distinct aquatic habitats Ganga River and Bhimsen Pond. Five fish of similar age and weight were selected, and the study was conducted during the summer, rainy, and winter seasons. Blood samples were collected by cardiac puncture and used for haematological and biochemical analyses. Haematological parameters including Hemoglobin (Hb), Total Erythrocyte Count (RBC), Total Leucocyte Count (WBC), and Hematocrit (HCT) were estimated using standard protocols. Serum was separated and analyzed for protein, glucose, cholesterol, and triglycerides. Additionally, muscle tissue samples were homogenized and analyzed for protein, glycogen and lipid content. Statistical analysis was performed using ANOVA, and a p-value < 0.05 was considered significant. The results showed significant seasonal fluctuations in haematological parameters. Highest values were found in summer and lowest in winter. Hb levels in river fish decreased from 7.86 g/dl in summer to 5.46 g/dl in winter (p = 7.98E-06). Similarly, RBCs, WBCs, and HCT also declined significantly with season. However, serum biochemical parameters (protein, glucose, cholesterol, and triglycerides) and muscle biochemical parameters (protein, glycogen, and lipid) did not reveal statistically significant seasonal variations (p > 0.05). Decreasing trends were found from summer to winter. This study highlights that haematological indices are more sensitive indicators of seasonal physiological responses in Labeo rohita than serum or muscle biochemistry, and such fluctuations may be influenced by environmental changes across seasons.