Hematological parameters of the hybrid serrasalmids farmed in Central-Western Brazil

Abstract

This study evaluated the hematological parameters of tambacu and patinga, two the hybrid serrasalmid fishes farmed in the state of Mato Grosso do Sul, Brazil, with emphasis on the influence of seasons on them. Two-hundred forty hybrid fishes, 120 tambacus and 120 patingas, were collected over 12 months to assess their hematological parameters and compare them between the warm (October-March) and cold seasons (April-September). Water quality parameters were also measured weekly to test for the influence of environmental conditions on the results. The dissolved oxygen content in the water decreased in the warm season, and increased in the cold season. In the warm season, tambacus presented significantly higher values (p<0.05) of the total plasmatic protein (TPP), hemoglobin, mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), and eosinophil count parameters. In the cold season, counts of erythrocytes, thrombocytes, total leukocytes, lymphocytes, and neutrophils were higher in tambacus (p<0.05). For patinga, MCV was higher in the warm season, while hemoglobin, erythrocytes, MCHC, total leukocytes, and basophil counts were higher (p<0.05) in the cold season. These results demonstrated the influences of seasonality on the hematological parameters of the hybrids tambacu and patinga when held under normal farming conditions in the region.