Association between the hematological characteristics and the biology of the “dourado” Salminus maxillosus Valenciennes, 1840 from Mogi-Guaçu River, state of São Paulo, Brazil

Abstract

In the present research 293 specimens of “dourado”, Salminus maxillosus Valenciennes, 1840, captured every month from August 1996 to December 1997, in Mogi-Guaçu River, downstream and upstream the dam of the Emas Falls (21°58' S - 47°26' W, 560 meters above sea level) were analyzed. The specimens were weighted (Wt - total weight, in grams) and measured (Lt - total length, in cm). Blood samples were taken to determine hematocrit (Ht), hemoglobin concentration (Hb), erythrocyte count (Er) and hematimetric indexes: MCV, MCH and MCHC. Sex and development stage were identified through macroscopic inspection of the gonads (immature, in maturation, mature, spent and resting). Mean values were calculated in relation to sex, gonadal maturation stage and class of total length. Results demonstrate that mean of hematological analyses did not differ significantly when sex, gonadal maturation stage and class of total length were evaluated. Correlation coefficients between hematological variables and between these and biological variables were also calculated, although not much correlation has been found in these analyses