Some Hematological and Physiological Indicators of Health in Triploid Tambaqui (Colossoma macropomum): A Preliminary Study

This study evaluated the physiological condition and health status of triploid tambaqui (<i>Colossoma macropomum</i>) using hematological and biochemical indicators. Hematocrit, hemoglobin concentration, erythrocyte count, glucose, and plasma protein levels (albumin, globulin and albumin/globulin ratio) were assessed in triploid and diploid fish, and mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) were calculated. Triploid fish exhibited larger erythrocytes, reduced erythrocyte counts, and slightly lower hemoglobin and hematocrit values compared with diploids. Correspondingly, MCV and MCH were significantly higher in triploids, indicating increased hemoglobin content per erythrocyte. In contrast, MCHC values did not differ between ploidy groups, suggesting that hemoglobin concentration within erythrocytes remained unaffected. No significant differences were observed in the evaluated biochemical parameters. These findings indicate that triploid tambaqui undergo compensatory physiological adjustments associated with increased nuclear DNA content in erythrocytes, enabling the maintenance of efficient oxygen transport and respiratory capacity. Overall, triploid fish displayed normal physiological performance, comparable to that of diploids. The results support the use of triploidy as a viable and sustainable strategy in tambaqui aquaculture.