Hematological profile of red drum Sciaenops ocellatus (Linnaeus, 1766) under natural and commercial feed nutritional conditions

This study was conducted to evaluate the effect of natural and commercial feeds on the hematological characteristics of red drum Sciaenops ocellatus. At different durations up to 30 days of feeding, blood samples were collected from the caudal vein. Biochemical analyses were conducted, and blood smears were prepared and stained with Giemsa. The results showed that the number of erythrocytes fluctuated from 2.07 to 6.32 × 106/μL, the percentage of leukocytes was about 0.34 to 4.80%, and platelets ranged from 0.14 to 4.49% compared to the number of erythrocytes. Pearson correlation (r) between the cell morphological parameters, such as the erythrocyte length and width, with the length, width and area of the nuclei of erythrocytes was not greater than 0.30, while in the group of fish consuming natural feed, the correlation coefficient between cell length and width with the area were 0.57 and 0.52 respectively. In both groups of fish, we found many types of morphological disorders of erythrocytes associated with the cell membrane, and disorders associated with the cell nucleus were expressed at a low level. In addition, the study results also provided biochemical data of red drum such as glucose (1.8 – 22.4 mmol/L), urea (0.6 – 1.7 mmol/L), creatinine (12.1 – 43.2 µmol/L), triglyceride (2.5 – 10.7 mmol/L), AST (4.7 – 68.9 U/L), ALT (0.3 – 6.1 U/L) and protein (21.0 – 49.2 g/L). Overall, these findings contribute to understanding the health and physiological responses of red drum, offering valuable data for optimizing feeding strategies in aquaculture.